HomeMy WebLinkAboutItem 3 Attachment 1 - TDPUD 2019 System Master Plan_Rev4
2019 ELECTRIC SYSTEM MASTER PLAN
Prepared For:
Truckee Donner Public Utility District
11570 Donner Pass Road
Truckee, California 96161
Prepared By:
Electrical Consultants, Inc.
3521 Gabel Road
Billings, MT 59102
Truckee Donner Public Utility District
2019 Electric System Master Plan Engineer’s Certification
ENGINEER'S CERTIFICATION
2019 Electric System Master Plan
Truckee Donner Public Utility District
11570 Donner Pass Road
Truckee, California 96161
Upon completion of construction of the facilities proposed herein, the system will provide
adequate and dependable service to approximately 13,923 customers and 57 MW of non-
coincidental load, as projected in the analysis.
The recommended system improvements included in this report are in general agreement with
the Truckee Donner Public Utility District Planning Criteria.
I certify that this report was prepared by me or under my direct supervision and that I am a
duly registered Professional Engineer.
Name Richard L. McComish, P.E.
November 2019
Date
Reg. No.
Truckee Donner Public Utility District
2019 Electric System Master Plan
Index
i
1.0 OVERVIEW & PURPOSE ........................................................................................ 1-1
1.1 Overview ............................................................................................. 1-1
1.2 Purpose ................................................................................................ 1-1
2.0 EXECUTIVE SUMMARY ....................................................................................... 2-1
2.1 Existing System Performance ............................................................. 2-1
2.2 Recommended System ........................................................................ 2-4
2.3 Contingency Analysis ......................................................................... 2-5
2.4 Cost Summary ..................................................................................... 2-5
2.5 Project Prioritization ........................................................................... 2-6
3.0 SYSTEM PLANNING CRITERIA ........................................................................... 3-1
3.1 Electrical System Performance Criteria……………………………...3-1
a. Distribution System Voltage Level……………………………….3-1
3.2 Voltage Regulation ............................................................................. 3-2
3.3 Phase Balancing .................................................................................. 3-3
3.4 Capacity and Loading ......................................................................... 3-5
a. Load Periods ................................................................................ ..3-5
b. Equipment Loading ...................................................................... ..3-5
c. Conductor ..................................................................................... ..3-6
3.5 Power Factor & Losses ....................................................................... 3-8
3.6 Contingency System Conditions ......................................................... 3-8
3.7 Mechanical Condition and Reliability Criteria ................................... 3-8
4.0 PROTECTION PHILOSOPHY ................................................................................. 4-1
4.1 Basic Principles of System Coordination ............................................ 4-1
4.2 Sectionalizers ...................................................................................... 4-1
4.3 Fuses ................................................................................................... 4-2
4.4 Electronic Recloser Applications ........................................................ 4-3
4.5 Safety Considerations ......................................................................... 4-3
4.6 Guide to Performed Calculations ........................................................ 4-4
5.0 HISTORICAL DATA & LOAD FORECAST .......................................................... 5-1
5.1 Description of Service Area ................................................................ 5-1
5.2 Power Supply ...................................................................................... 5-1
a. Energy Efficiency and Conservation ........................................... ..5-1
5.3 Transmission ....................................................................................... 5-1
5.4 Connection Statistics & Growth Patterns ............................................ 5-1
a. Residential.................................................................................... ..5-2
b. Commercial (< 50 kW) ................................................................ ..5-2
c. Commercial (> 50 kW and < 200 kW) ........................................ ..5-2
d. Commercial (> 200 kW) .............................................................. ..5-2
e. Public Authority ........................................................................... ..5-3
f. Water Pump ................................................................................. ..5-3
g. The District Use ........................................................................... ..5-3
5.5 Line Statistics .................................................................................... 5-12
5.6 Historical Demand and Growth Patterns .......................................... 5-13
Truckee Donner Public Utility District
2019 Electric System Master Plan
Index
ii
5.7 System Load Factor .......................................................................... 5-14
5.8 Reliability of Electric Service ........................................................... 5-15
5.9 Annual System Demand ................................................................... 5-15
5.10 Status of Previous Master Plan Items ............................................... 5-16
6.0 CONSTRUCTION RECOMMENDATIONS ........................................................... 6-1
a. Loading and Capacity .................................................................. .6-1
b. Mechanical Condition of Plant .................................................... .6-1
c. System Analysis ........................................................................... .6-1
d. Contingency System Planning ..................................................... .6-1
e. Sectionalizing Recommendations ................................................ .6-1
Tables 6-2
6.1 DONNER LAKE SERVICE AREA ................................................... 6-4
6.2 GLENSHIRE SERVICE AREA ......................................................... 6-9
6.3 MARTIS VALLEY SERVICE AREA ............................................. .6-11
6.4 TAHOE DONNER SERVICE AREA .............................................. .6-15
6.5 TRUCKEE SERVICE AREA ........................................................... .6-20
6.6 SYSTEM WIDE IMPROVEMENTS ............................................... .6-26
APPENDICES
Costs
Maps
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 1.0
1-1
1.0 OVERVIEW & PURPOSE
1.1 Overview
This report contains an analysis of the present system and the 2019 Electric System Master
Plan for Truckee Donner Public Utility District (the District or TDPUD). The Executive
Summary, Section 2, contains the required information for the District's management to
include in long-range financial forecasts and a summary of the recommended plan. The
Planning and Sectionalizing Criteria is described in Sections 3 and 4 respectively, while
Section 5 provides a review of historical trends and load forecasts. Section 4 includes the
philosophy used by the Engineer to provide proper coordination between the protective
devices in the District’s system. Section 5 of this report examines performance of the
existing distribution system for voltage drop, voltage and current imbalance, line loading,
equipment capacity, power factor and losses with present peak, projected 5 and 15 year
peak conditions.
1.2 Purpose
The main purpose of this report is to provide Truckee Donner Public Utility District with
an orderly plan for carrying out construction, protective coordination and other needed
improvements. Complementary to this purpose is the study’s goal of planning and
completing improvements in the most economic manner possible.
A second major purpose of this report is to provide the most up-to-date forecast possible
of financial requirements for the next 15 years. These cost estimates provide the utility with
the data necessary for completion of their annual business work plans and budgets and
serve as a basis for long-term financial forecasts.
Service reliability and quality of service are the very essence of operational goals in any
electric utility. The function of system planning is to evaluate the existing and projected
system configuration, voltage levels and load balance in a manner that endeavors to
increase the quality of service. In a continuing effort and in order to serve its intended
purpose, planning must change dynamically as governing conditions change. This plan
provides the Owners’ and Engineers’ current philosophy on those specific improvements
which will best meet the present needs of the system.
In addition to the Master Plan construction recommendations, a detailed sectionalizing
study was completed to provide the best possible protection for the utility and consumers.
This evaluation of the system takes into consideration the following items:
· Increased fault levels due to system improvements
· Loading of equipment
· Reliability
Taking into account each of the above items, the system was evaluated to ensure that all
devices met maximum interrupt rating, while not exceeding their continuous current
ratings, and that devices would pick up minimum fault currents based on a 40 ohm ground
resistance. Proper coordination between devices was also evaluated in an attempt to
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 1.0
1-2
eliminate simultaneous operation. As a result of this evaluation, the sectionalizing study
provides recommendations which will enable the District to provide a high level of
reliability to its customers.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 2.0
2-1
2.0 EXECUTIVE SUMMARY
This report presents the results of a Master Plan prepared by Electrical Consultants, Inc.
(ECI) for Truckee Donner Public Utility District (the District). This study evaluates the
District’s distribution system which provides electric service in Northeastern California.
Based upon the planning criteria identified in Section 3.0 and pertinent historical trends
and load forecasts identified in Section 5.0, distribution system performance was evaluated
in order to identify criteria violations for voltage drop, voltage and current imbalance, line
and equipment loading, as well as power factor and losses.
System performance was evaluated by first performing load flows for peak loading
conditions. A thorough review of the existing system performance with the present,
transition (5 year) and long range (15 year) loading was performed. The peak model is
represented by the existing system maps located in the Appendix, which include voltage
loading levels through the District’s distribution system. Results of the load flow analysis
are summarized in Section 6.0 along with recommendations for system improvement.
After load growth was implemented in the model, protective device settings were updated
to reflect the existing system. Changes are recommended where minimum pick up levels
are above minimum fault current levels within the protection zones. Other
recommendations provided within this report provide increased coordination intervals and
new sectionalizing points. Most of the improvements are considered minor in nature and
would bring the District’s system reliability to a higher level.
All feeders on the District’s system utilize an electronic recloser for feeder protection. All
of these controls, with the exception of Glenshire, have high current trip (HCT) and high
current lock out (HCL) enabled on the controls. Ideally, the use of HCT and HCL will trip
and lock out a recloser for a fault on the main underground feeder. Setting changes are
recommended to many of the reclosers to increase the trip levels on the HCT and HCL to
allow down line faults to be cleared by tap fuses while the feeder recloser only lock out for
a close in fault on the underground.
All recommendations were designed to be in general concurrence with planning criteria
and to ensure that no adverse impacts to the integrity of the District’s system were imposed.
The mechanical condition of the District’s plant, along with reliability of service to
members, was also factored into the recommendations for system improvement. Single
contingency outages were investigated through analysis of load flow and voltage drop
studies to address system requirements during such operating conditions.
2.1 Existing System Performance
Figure 2-2-1 displays the District’s system kW demands since 1991 and projected 15 year
usage based upon historic load data and least squares statistical regression technique. The
non-coincidental peak load that was utilized for the load flow analysis was 47 MW for
existing system loads. In consideration of potential growth over the 15 year study period,
53 MW was utilized for projected 5 year growth and 57 MW was utilized for projected 15
year growth.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 2.0
2-2
Analysis of existing systems shows no substations have voltage less than 116.0 volts. This
means that in its current shape, there are very few improvements that will be required
during the next 15 years.
ANSI C84.1-2011 sets normal voltage levels for equipment on a distribution system.
Minimum service voltage set by this standard is 114.0 volts under normal operating
conditions. Service voltage is defined as the connected point between the customer and the
utility, which is considered the meter. Analysis of the District’s system consisted of voltage
drop on the primary line and did not account for voltage drop from the transformer to the
meter. A minimum voltage of 118.0 volts on the primary line allows for a 4.0 volt drop
through the transformer and secondary wire to the meter. Refer to Section 3.0, System
Planning Criteria, for voltage criteria used for system planning and other criteria.
Conductor loading over 80% was noted for the existing system in the Donner Lake service
area. At the projected fifteen (15) year loads, additional conductor overloading was also
noted in the Donner Lake service area on Feeder 1.
A single contingency load transfer of each substation was performed with existing as well
as projected 5 and 15 year loads. This single contingency assumes a loss of substation
service transferring feeders to adjacent service areas. Complete load transfer of all
substations be accomplished under peak loading conditions. The balance of the substations
could be transferred to adjacent substations; however, voltage levels fell below planning
criteria, where transformer and conductor overloading was also noted during these load
transfers.
Figure 2-2-1
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 2.0
2-3
2.2 Recommended System
Improvements were recommended for the Electric System Master Plan which would first
improve voltage levels under peak loading conditions for both existing and projected 15
year loads. Phase balancing was also recommended for the existing system to not only
improve voltage levels but to reduce losses.
Single phase taps with greater than 30 amps of load should be considered for rebuild to
three-phase to allow for more effective phase balancing throughout the system. It was
recommended to use minimum standard conductor size of 2/0 AWG ACSR for these
rebuilds, however, local demographics may warrant the use of smaller conductors, such as 2
AWG ACSR, in areas of anticipated low growth.
The following is an overview of the major projects recommended for the District’s service
area:
· Rebuilding of the three-phase line from Davos Dr. and Northwood Blvd. at the
substation to Fjord Rd. and Northwood Blvd. This project is required to improve
voltage during transfer to Donner Lake to above 114.0 V. It will also improve loading,
as the existing conductor is over 100% loading during contingency.
· The District is interested in installing a photovoltaic system on the District headquarters
building in 2020. Not only would the District be reducing its own carbon footprint, all
of the District’s customers would benefit with a lower District complex electric bill.
Additionally, all generation would count towards the District’s renewable portfolio
requirements.
· The District has completed 4 phases of optical communication line installation. Four
additional phases are expected to be required for connection to all remaining District
facilities. At completion, there will be a redundant network to all facilities, with 2
distinct physical paths from each facility back to the main office.
· Upgrading the Truckee Substation transformers to either a set of three (3) 8.3 MVA
single-phase transformers or a 25 MVA three-phase transformer in order to provide
load transfer capability between Martis Valley and Truckee substations when Martis
Valley is cleared at 15-year loading levels.
· The District will replace all T-link expulsion fuses with ELF current limiting fuses in
Tahoe Donner by 2022.
TDPUD’s standard fuse manufacturer and type are Kearney Type T fuses. The Kearney
fuse has a relatively quick clearing time on a majority of the fuse sizes. It is recommended
that all taps off of the main three-phase line be fused, so as not to have an outage on a
short tap, resulting in a feeder recloser going to lock-out. For each feeder on the system,
there is a fuse coordination table listed, showing maximum T fuse size to be used with up-
line reclosers. On longer taps, it is recommended that the tap be fused and additional fuses
down-line be used to increase coordination. This will not only improve reliability, but also
aid in locating faults.
It is important to fuse the single-phase taps off from the main three-phase line to improve
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 2.0
2-4
reliability. This is especially true on short taps where a two or three span tap with a fault
would result in the feeder seeing the blink or having an outage.
2.3 Contingency Analysis
Using the recommended model as a basis, contingency analysis was performed. Currently
there is load transfer capability between all of the substations for individual feeders.
There are a large number of existing possible contingency options between substations,
which allows for a wide array of possible load transfers. All possible contingency options
between feeders of different substations were analyzed and projects were provided in order
to make load transfer possible in the case of a total substation outage.
2.4 Cost Summary
Table 2-4-1 through Table 2-4-4 show recommended and contingency project costs by
substation and priority year.
Project CodeMiles/ QtyConstruction Description Unit CostTotal CostSub MulPriorityRecommended CostTable 2-4-1TDPUDSubstation:District WideFO-011$875,000SCADA Reliability Improvement Project Phase 5 Install $875,000District Wide 11FO-021$100,000SCADA Reliability Improvement Project Phase 6 Design $100,000District Wide 12FO-031$500,000SCADA Reliability Improvement Project Phase 6 Install $500,000District Wide 13FO-041$300,000SCADA Reliability Improvement Project Phase 7 Design $300,000District Wide 14FO-051$850,000SCADA Reliability Improvement Project Phase 7 Install $850,000District Wide 15FO-061$350,000SCADA Reliability Improvement Project Phase 8 Design $350,000District Wide 16FO-071$850,000SCADA Reliability Improvement Project Phase 8 Install $850,000District Wide 17FO-081$650,000SCADA Reliability Improvement Project Phase 9 Design $650,000District Wide 18FO-091$650,000SCADA Reliability Improvement Project Phase 9 Install $650,000District Wide 19FUS-011$225,000CL Fuse Installations - Tahoe Donner$225,000District Wide 11FUS-021$250,000CL Fuse Installations - Tahoe Donner$250,000District Wide 12Friday, November 15, 2019Page 1 of 4
Project CodeMiles/ QtyConstruction Description Unit CostTotal CostSub MulPriorityRecommended CostTable 2-4-1TDPUDFUS-031$300,000CL Fuse Installations - Tahoe Donner$300,000District Wide 13FUS-041$400,000CL Fuse Installations - Prosser Lakeview$400,000District Wide 14FUS-051$300,000CL Fuse Installations - Prosser Lakeview$300,000District Wide 15FUS-061$300,000CL Fuse Installations - Prosser Lakeview$300,000District Wide 16SRP-011$150,000Solar Awning Project$150,000District Wide 11SYS-01A50$6,000Pole Replacements$300,000District Wide 11SYS-02A50$6,000Pole Replacements$300,000District Wide 12SYS-03A50$6,000Pole Replacements$300,000District Wide 13SYS-04A50$6,000Pole Replacements$300,000District Wide 14SYS-05A50$6,000Pole Replacements$300,000District Wide 15$8,550,000Total District Wide CostSubstation:Donner LakeFriday, November 15, 2019Page 2 of 4
Project CodeMiles/ QtyConstruction Description Unit CostTotal CostSub MulPriorityRecommended CostTable 2-4-1TDPUDDL-01.46$254,950Rebuild 1-phase #2 AWG ACSR with 3-phase #2 AWG ACSR$117,000Donner Lake 13DL-02.1$254,950Rebuild 1-phase #2 AWG ACSR with 3-phase #2 AWG ACSR$25,000Donner Lake 14DL-SEC1$15,000R30 Replacement$15,000Donner Lake 11$157,000Total Donner Lake CostSubstation:GlenshireGL-01a1$100,000Engineering for installation of step up transformer$100,000Glenshire 11GL-01b1$750,000Install Glenshire Autotransformer Equipment $750,000Glenshire 12$850,000Total Glenshire CostSubstation:Martis ValleyMV-01a1$50,000Engineering for substation upgrades$50,000Martis Valley 11MV-01b1$200,000MVAL Circuit Switcher Replacement and other upgrades $200,000Martis Valley 12MV-SEC1$15,000R35 Replacement$15,000Martis Valley 11$265,000Total Martis Valley CostSubstation:Tahoe DonnerFriday, November 15, 2019Page 3 of 4
Project CodeMiles/ QtyConstruction Description Unit CostTotal CostSub MulPriorityRecommended CostTable 2-4-1TDPUDTD-04.7$278,142Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$195,000Tahoe Donner 12TD-SEC1$30,000R20 and R50 Replacement$30,000Tahoe Donner 11$225,000Total Tahoe Donner CostSubstation:TruckeeTR-01.22$254,545Rebuild 1-phase #2 AWG ACSR with 3-phase #2 AWG ACSR$56,000Truckee 15TR-021.22$382,425Rebuild 1-phase #2 AWG ACSR with 3-phase #2 AWG ACSR$467,000Truckee 11TR-031$970,000Sub control house and containment improv.$970,000Truckee 11$1,493,000Total Truckee Cost$11,540,000Total Recommended CostFriday, November 15, 2019Page 4 of 4
Project CodeMiles/ QtyConstruction DescriptionUnit CostTotal CostFeederSubstation/ Item PriorityRecommended Cost by YearTable 2-4-2TDPUDDL-SEC1$15,000R30 Replacement$15,000DL-3Donner Lake 1FO-011$875,000SCADA Reliability Improvement Project Phase 5 Install$875,000DistrictDistrict Wide 1FUS-011$225,000CL Fuse Installations - Tahoe Donner$225,000DistrictDistrict Wide 1GL-01a1$100,000Engineering for installation of step up transformer$100,000GL-1Glenshire 1MV-01a1$50,000Engineering for substation upgrades$50,000Martis Valley 1MV-SEC1$15,000R35 Replacement$15,000MV-2Martis Valley 1SRP-011$150,000Solar Awning Project$150,000DistrictDistrict Wide 1SYS-01A50$6,000Pole Replacements$300,000DistrictDistrict Wide 1TD-SEC1$30,000R20 and R50 Replacement$30,000TD-1Tahoe Donner 1TR-021.22$382,425Rebuild 1-phase #2 AWG ACSR with 3-phase #2 AWG ACSR$467,000TR-5Truckee 1TR-031$970,000Sub control house and containment improv. $970,000Truckee 1$3,197,000Total Year 1 CostFO-021$100,000SCADA Reliability Improvement Project Phase 6 Design$100,000DistrictDistrict Wide 2FUS-021$250,000CL Fuse Installations - Tahoe Donner$250,000DistrictDistrict Wide 2GL-01b1$750,000Install Glenshire Autotransformer Equipment $750,000GL-1Glenshire 2Friday, November 15, 2019Page 1 of 3
Project CodeMiles/ QtyConstruction DescriptionUnit CostTotal CostFeederSubstation/ Item PriorityRecommended Cost by YearTable 2-4-2TDPUDMV-01b1$200,000MVAL Circuit Switcher Replacement and other upgrades$200,000Martis Valley 2SYS-02A50$6,000Pole Replacements$300,000DistrictDistrict Wide 2TD-04.7$278,142Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$195,000TD-2Tahoe Donner 2$1,795,000Total Year 2 CostDL-01.46$254,950Rebuild 1-phase #2 AWG ACSR with 3-phase #2 AWG ACSR$117,000DL-3Donner Lake 3FO-031$500,000SCADA Reliability Improvement Project Phase 6 Install$500,000DistrictDistrict Wide 3FUS-031$300,000CL Fuse Installations - Tahoe Donner$300,000DistrictDistrict Wide 3SYS-03A50$6,000Pole Replacements$300,000DistrictDistrict Wide 3$1,217,000Total Year 3 CostDL-02.1$254,950Rebuild 1-phase #2 AWG ACSR with 3-phase #2 AWG ACSR$25,000DL-3Donner Lake 4FO-041$300,000SCADA Reliability Improvement Project Phase 7 Design$300,000DistrictDistrict Wide 4FUS-041$400,000CL Fuse Installations - Prosser Lakeview$400,000DistrictDistrict Wide 4SYS-04A50$6,000Pole Replacements$300,000DistrictDistrict Wide 4$1,025,000Total Year 4 CostFO-051$850,000SCADA Reliability Improvement Project Phase 7 Install$850,000DistrictDistrict Wide 5Friday, November 15, 2019Page 2 of 3
Project CodeMiles/ QtyConstruction DescriptionUnit CostTotal CostFeederSubstation/ Item PriorityRecommended Cost by YearTable 2-4-2TDPUDFUS-051$300,000CL Fuse Installations - Prosser Lakeview$300,000DistrictDistrict Wide 5SYS-05A50$6,000Pole Replacements$300,000DistrictDistrict Wide 5TR-01.22$254,545Rebuild 1-phase #2 AWG ACSR with 3-phase #2 AWG ACSR$56,000TR-1Truckee 5$1,506,000Total Year 5 CostFO-061$350,000SCADA Reliability Improvement Project Phase 8 Design$350,000DistrictDistrict Wide 6FUS-061$300,000CL Fuse Installations - Prosser Lakeview$300,000DistrictDistrict Wide 6$650,000Total Year 6 CostFO-071$850,000SCADA Reliability Improvement Project Phase 8 Install$850,000DistrictDistrict Wide 7$850,000Total Year 7 CostFO-081$650,000SCADA Reliability Improvement Project Phase 9 Design$650,000DistrictDistrict Wide 8$650,000Total Year 8 CostFO-091$650,000SCADA Reliability Improvement Project Phase 9 Install$650,000DistrictDistrict Wide 9$650,000Total Year 9 Cost$11,540,000Total Recommended CostFriday, November 15, 2019Page 3 of 3
Project CodeMiles/ QtyConstruction Description Unit CostTotal CostFeeder Sub MulYr of ImprovContingency CostTable 2-4-3TDPUDDL-C1.35$284,200Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$99,470TR-4 Truckee 18DL-C22$37,500Install S&C PMH-9, Pad-Mtd. Switchgear, 15 kV Equipment$75,000DL-2 Donner Lake 18DL-C4.77$283,450Rebuild 2-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$218,257DL-2 Donner Lake 110DL-C51$60,000Install 328 amp, 250 kVA Equipment$60,000MV-3 Martis Valley 112DL-C6.8$278,200Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$222,560DL-3 Donner Lake 15MV-C31$950,000Install three (3) single-phase 7.5 MVA transformers$950,000MV-1 Martis Valley 16MV-C6.2$282,700Rebuild 1-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$56,540MV-3 Martis Valley 18MV-C7.08$913,357Rebuild 3-phase 500 kcmil 260 MIL EPR with 3-phase 750 MCM$73,069MV-4 Martis Valley 115TD-C2.83$278,200Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$230,906TD-1 Tahoe Donner 11TD-C3.74$278,200Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$205,868TD-1 Tahoe Donner 14TD-C4.67$278,200Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$186,394TD-3 Tahoe Donner 11TD-C51$278,000Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$278,000TD-2 Tahoe Donner 11TR-C1.33$284,200Rebuild 3-phase #2 AWG ACSR with 3-phase 397 kcmil AAC$93,786TR-3 Truckee 17TR-C2.59$284,200Rebuild 3-phase #4/0 AWG ACSR with 3-phase 397 kcmil AAC$167,678TR-2 Truckee 111TR-C3.15$913,330Rebuild 3-phase #500 MCM with 3-phase 750 AWG EPR$137,000TR-2 Truckee 113TR-C41$750,000Install three (3) single-phase 7.5 MVA transformers$750,000TR-2 Truckee 114TR-C5.18$284,200Rebuild 3-phase #4/0 AWG ACSR with 3-phase 397 kcmil AAC$51,156TR-2 Truckee 112Thursday, November 14, 2019Page 1 of 2
Project CodeMiles/ QtyConstruction Description Unit CostTotal CostFeeder Sub MulYr of ImprovContingency CostTable 2-4-3TDPUDTR-C6.04$913,357Rebuild 3-phase #500 MCM with 3-phase 750 MCM$36,534TR-2 Truckee 112$4,883,757Total Contingency CostThursday, November 14, 2019Page 2 of 2
Project CodeMiles/ QtyConstruction Description Unit CostTotal CostTDPUDFeederSubstation/ ItemYr of ImprovContingency Cost by YearTable 2-4-4TD-C2.83$278,200Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$230,906TD-1Tahoe Donner 1TD-C4.67$278,200Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$186,394TD-3Tahoe Donner 1TD-C51$278,200Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$278,000TD-2Tahoe Donner 1$834,400Total Year 1 CostTD-C3.74$278,200Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$205,868TD-1Tahoe Donner 4$278,200Total Year 4 CostDL-C6.8$278,200Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$222,560DL-3Donner Lake 5$278,200Total Year 5 CostMV-C31$350,000Install three (3) single-phase 7.5 MVA transformers$950,000MV-1Martis Valley 6$950,000Total Year 6 CostTR-C1.33$278,200Rebuild 3-phase #2 AWG ACSR with 3-phase 397 kcmil AAC$93,786TR-3Truckee 7$91,806Total Year 7 CostDL-C1.35$278,200Rebuild 3-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$99,470TR-4Truckee 8DL-C22$23,669Install S&C PMH-9, Pad-Mtd. Switchgear, 15 kV Equipment$75,000DL-2Donner Lake 8MV-C6.2$278,200Rebuild 1-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$56,540MV-3Martis Valley 8Thursday, November 14, 2019Page 1 of 3
Project CodeMiles/ QtyConstruction Description Unit CostTotal CostTDPUDFeederSubstation/ ItemYr of ImprovContingency Cost by YearTable 2-4-4$190,510Total Year 8 CostDL-C4.77$278,200Rebuild 2-phase #2/0 AWG ACSR with 3-phase 397 kcmil AAC$218,257DL-2Donner Lake 10$214,214Total Year 10 CostTR-C2.59$278,200Rebuild 3-phase #4/0 AWG ACSR with 3-phase 397 kcmil AAC$167,678TR-2Truckee 11$164,138Total Year 11 CostDL-C51$20,697Install 328 amp, 250 kVA Equipment$60,000MV-3Martis Valley 12TR-C5.18$278,200Rebuild 3-phase #4/0 AWG ACSR with 3-phase 397 kcmil AAC$51,156TR-2Truckee 12TR-C6.04$907,357Rebuild 3-phase #500 MCM with 3-phase 750 MCM $36,534TR-2Truckee 12$146,370Total Year 12 CostTR-C3.15$84,480Rebuild 3-phase #500 MCM with 3-phase 750 AWG EPR $137,000TR-2Truckee 13$913,330Total Year 13 CostTR-C41$350,000Install three (3) single-phase 7.5 MVA transformers$750,000TR-2Truckee 14$750,000Total Year 14 CostMV-C7.08$907,357Rebuild 3-phase 500 kcmil 260 MIL EPR with 3-phase 750 MCM$73,069MV-4Martis Valley 15Thursday, November 14, 2019Page 2 of 3
Project CodeMiles/ QtyConstruction Description Unit CostTotal CostTDPUDFeederSubstation/ ItemYr of ImprovContingency Cost by YearTable 2-4-4$72,589Total Year 15 Cost$4,883,757Total Contingency CostThursday, November 14, 2019Page 3 of 3
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 2.0
2-5
2.5 Project Prioritization
The first aspect to consider when determining a project’s priority is whether the project is
for the normal system improvement or for a contingency improvement. Normal system
improvements would have first priority over a contingency improvement. The next
consideration would be voltage levels of the system and at what year those voltage levels
fall below planning criteria. Projects required to correct voltage for a transition period or
long range period would have a lower priority than those needed to correct the existing
system. The next item to consider would be the number of customers being served in the
area requiring the project. An area with a high number of projects, although it may not have
as low of voltage as other areas, would have a higher priority.
The last item to consider would be budget constraints in completing the project. Some
systems may require a number of projects to correct existing system voltages requiring a
large portion of the overall projects be completed within the first few years of the plan.
However, this may not be feasible and would require that the projects be spread over a
number of years, even though they are required as soon as possible. In these cases, the best
approach is to try to complete projects that provide the most for your money. For example,
completing a number of three-phase projects to allow phase balancing, improving voltage
in a number of areas versus one major line rebuild.
Although the plan may prioritize projects, it is best to spread them over the planning period.
Projects may need to be prioritized due to events of construction that may occur at an earlier
time frame. For example, a project may be slated for year five, however, the county has just
informed the District that it is going to rebuild a road in that area and that the line would
need to be rebuilt, resulting in this project construction being moved up by three years.
Another example may be that a subdivision did not develop as planned and that project
may be moved back until such time that the subdivision is constructed.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 3.0
3-1
3.0 SYSTEM PLANNING CRITERIA
The design criteria presented within this section was used to guide the development of the
2019 Electric System Master Plan. Criteria were developed to provide minimum standards
for all system improvement, operation, and maintenance activities affecting system
facilities. Compliance with these minimum standards will result in adequate voltage,
acceptable thermal loading of system components, and a distribution system capable of
providing safe, reliable service.
This study considers quality of service and service continuity to be critical issues to the
District. Geographical conditions, including occasions of severe inclement weather in this
service area, serve as a factor in the results. Meeting established criteria will help the
District maintain an excellent quality of service to their consumers. The District has, and
will continue to, utilize current technologies to improve the quality of service to the
membership, allow efficient operations, and provide the ability to gather data to evaluate
potential improvements to the system.
All criteria were established jointly between Electrical Consultants, Inc. (ECI) and Truckee
Donner Public Utility District (the District).
3.1 Electrical System Performance Criteria
This section describes basic electrical performance criteria for the system for both normal
and contingency operating conditions. Regulated load flows were utilized for by-phase
analysis of the performance of the District’s system.
a. Distribution System Voltage Level
Voltage levels for the plan are defined with regulated substation bus voltage set to
124.0 volts during all seasons for purposes of the voltage drop study. Maximum
voltage at any point of the distribution feeders is limited to 126.0 volts.
The system developed for the plan period is designed to maintain 118.0 volts at all
distribution transformer primaries. This 118.0-volt limit is consistent with ANSI
standards which specify 114.0 volts minimum to the consumer premises where the
additional 4.0 volts drop represents service transformer and service wire drop.
For contingencies, the system developed for the plan period is designed to maintain
voltage levels of 114.0 volts at the primary terminals of any distribution transformer
on the system. For voltage levels below 114.0 volts during contingencies,
improvements will be recommended.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 3.0
3-2
Voltage
Class
Nominal
System
Voltage
Nominal
Utilization
Voltage
Voltage Range A Voltage Range B
Maximum Minimum Maximum Minimum
3-wire 3-wire Utilization and
Service Voltage
Service
Voltage
Utilization
Voltage
Utilization and
Service Voltage
Service
Voltage
Utilization
Voltage
Low
Voltage
Single-Phase Systems
120-240 115
115/230
126
126/252
114
114/228
110
110/220
127
127/254
110
110/220
106
106/212
Standard Nominal System Voltages and Voltage Ranges
Table 3-1-1
As defined by ANSI C84.1-2011:
Service Voltage: The voltage at the point where the electrical system of the supplier
and the electrical system of the user are connected.
Utilization Voltage: The voltage at the line terminals of utilization equipment.
Range A: Electrical supply systems shall be so designed and operated that
most service voltages will be within the limits specified for Range
A. The occurrence of service voltages outside of these limits should
be infrequent.
Range B: Range B includes voltages above and below Range A limits that
necessarily result from practical design and operating conditions on
supply or user systems, or both. Although such conditions are a part
of practical operations, they shall be limited in extent, frequency,
and duration. When they occur, corrective measures shall be
undertaken within a reasonable time to improve voltages to meet
Range A requirements.
3.2 Voltage Regulation
This section describes the application of a load tap changer (LTC), voltage
regulator, line drop compensation, first house protection, and reverse power flow
devices. Upon installation of regulators in the recommended plan, the R and X
values will be computed to assure optimal settings. The criteria utilized in this study
include, but are not limited to, the following:
a. Voltage limit settings of 126.0 volts for first house protection shall be
utilized whenever possible to prevent excessive voltage to consumers.
Significant consideration to voltage regulator compensation settings
shall be given to assure that regulator controls do not inadvertently
result in “out of criteria” voltages during peak loading conditions.
b. In lieu of regulating the substation bus, line drop compensation (LDC)
settings attempt to regulate a level of system voltage at a theoretical
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 3.0
3-3
load center on the feeder by adjusting voltage levels as a function of
power flow. LDC settings will cause voltage at the substation bus and
end-of-line to fluctuate, while attempting to maintain a relatively fixed
voltage near the center of the feeder. Without LDC, bus voltage
remains fairly constant with relatively large voltage fluctuations at
remote points on the feeder. Use of LDC may create problems for large
industrial, or other voltage sensitive customers located near the
substation, due to the frequency and magnitude of system voltage
changes.
c. In order to maximize the use of the distribution system, it is necessary
to operate the substation tap changers/regulators to adequately
compensate for swings in the transmission voltage and provide a
sufficient voltage range for allocation across the distribution system.
d. Feeder regulation, instead of bus regulation, will be considered at
substations where the loading conditions or load density vary
significantly between feeders.
e. Reverse power flow will be considered at strategic locations for load
transfer between feeders that can be source fed from either direction.
f. Regulation at the substation, as well as one stage of regulation installed
on the feeder, is acceptable in all system design, however, cascaded
feeder regulators will be considered on a case-by-case basis. Cascaded
regulators may provide the best long-term solution for load transfer on
feeders where capacity is not the limiting condition.
3.3 Phase Balancing
If the load on the feeder is poorly balanced between phases, reasonable measures
should be taken to achieve balance. Balanced conditions mean equal current in each
phase with corresponding minimum regulation at system design loading.
Unbalanced feeders can result in poor voltage regulation, unnecessarily increased
line losses, and facilities that may be overloaded. This is possible even if the total
three-phase load is not excessive. An ideal design, although usually not achievable
in practice, will provide load balance throughout the entire feeder, not just at the
substation. If a feeder serves only three-phase load, then balance is typically not a
problem. Phase balance is also a primary concern when considering sectionalizing.
The following items provide a general indication of potential phase balance
problems. To be most effective, attempts shall be made to achieve good balance at
system design loading.
a. Substation Transformer Unbalance – Goals of balancing
substation loads include maintaining balanced flow of power on the
distribution system and reducing the risk of transformer bank
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 3.0
3-4
Protective device operation. The percentage unbalance
recommended allows a reasonable margin for the effects of
downstream sectionalizing during contingencies. Substation
unbalance, as defined at the end of this section, should not exceed
25%, or 75 amps, whichever is less, where practical.
b. Feeder Unbalance at Substations – The purpose of these criteria
is to maintain balanced flow of power on the distribution system and
reduce the risk of overloading of the substation feeder and protective
devices, as well as the substation transformers. For feeders where
the highest loaded phase is 149 amps or less, unbalance should not
exceed 40% or 50 amps, whichever is less. For feeders where the
highest loaded phase is 150 amps or more, unbalance should not
exceed 25% or 75 amps, whichever is less.
c. Feeder/Tap Unbalance – The purpose of limiting unbalance in
downstream feeders is to maintain balanced flow of power on the
distribution system and reduce system losses and voltage drop. For
locations where the highest loaded phase is 149 amps or less,
unbalance should not exceed 24% or 30 amps, whichever is less. For
locations where the highest loaded phase is 150 amps or more,
unbalance should not exceed 25% or 100 amps, whichever is less.
For single-phase taps with greater than 30 amps, extension of three-
phase should be considered.
d. Voltage Unbalance – Normally, when loads are balanced, voltages
will also be balanced. However, phase voltages may not be balanced
due to unbalance in loading. Based on ANSI/IEEE Standard 141-
1993, the target for maximum allowable voltage unbalance is 2%.
The formula to calculate such unbalance is:
VoltageUnbalance =
Maximum Difference Phase Voltage - Average Voltage
Average Voltage
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 3.0
3-5
3.4 Capacity and Loading
This section defines criteria related to equipment loading, including the effect of seasonal
conditions and ratings, to be considered.
a. Load Periods
Winter peak loading conditions generally determine the system peak for the
District.
b. Equipment Loading
A key objective of this plan is to maintain peak feeder loading during normal system
conditions at desired loading levels to allow for load transfer and protective
coordination. Normal system loading is generally desired to be a maximum of 80%
conductor loading and 50% conductor loading for feeder ties to allow load transfer.
Equipment loading, expressed as a percent of nameplate rating, should not exceed
the following:
Transformers – A transformer shall not be thermally loaded by more than
the following percentage of its nameplate rating:
Continuously loaded to 125% of OA rating (no fans) during average winter
daily temperatures of 32°F (0°C) plus 5°C margin.
Continuously loaded to 100% of OA rating (no fans) during average
summer daily temperature of 72°F (22°C) plus 5°C margin.
The above limits are based on Table 3 of IEEE Standard C57.91-2011 edition,
shown on the following page.
Table 3 of IEEE Standard C57.91-2011
Loading on Basis of Temperatures
(Ambient other than 30°C and Average Winding Rise Less than Limiting Values)
(For Quick Approximation)
(Ambient Temperature Range 0°C to 50°C)
Type of Cooling
% of Rating
Decrease Load for Each °C
Higher Temperature
Increase Load for Each °C
Lower Temperature
Self-cooled – ONAN 1.5 1.0
Water-cooled – ONWF 1.5 1.0
Forced-air-cooled – ONAN/ONAF,
ONAN/ONAF/ONAF 1.0 0.75
Forced-air-cooled – OFAF, OFWF, ODWF, and
ONAN/OFAF/OFAF 1.0 0.75
*See 5.1 in IEEE Std C57.12.00-2010.
-average ambient other than 30 ° C and average winding rise less than limiting values, for quick approxim ation, ambient temperature range –30 ° C to 50 ° C
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 3.0
3-6
Table 3-4-1 lists substation transformer ratings.
Substation Transformer Size °C
Donner Lake 12 MVA 65°
Glenshire N/A N/A
Martis Valley 3-1PH 5 MVA 55°
Tahoe Donner 3-1PH 5 MVA 55°
Truckee 3-1PH 5 MVA 55°
Substation Transformer
Table 3-4-1
Substation and Line Voltage Regulators – Substation and line voltage
regulators shall be monitored for possible replacement at 80% loading
on feeders with high load factors during summer peak conditions and
100% during other seasonal conditions. Consideration to increase
loading capability by limiting the tap range is given for substation
regulators as an alternative to replacement.
Hydraulic Circuit Reclosers – Hydraulic circuit reclosers should not be
loaded more than 80% during peak and load transfer conditions.
Excessive loading of these devices can cause inadvertent oil flow in the
device timing mechanism, causing reduced operating time and possible
mis-coordination.
Electronically Controlled Reclosers and Relay Controlled Breakers –
Electronically controlled reclosers and relay controlled breakers should
not be loaded more than 100% during peak conditions, including load
transfer conditions.
c. Conductor
Primary conductors should not to be loaded over 80% of their thermal rating under
normal service conditions, especially when age and condition elements are present.
In addition, loading should be conservatively determined to provide sufficient load
transfer capability.
Primary conductor sizing for improvements will be determined on a case-by-case
basis using the following criteria:
a. Economic conductor size; and
b. Minimum size for main three phase line segments for contingency load
transfers determined necessary and practical between the District and ECI.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 3.0
3-7
c. The District’s standard conductor sizes are as follows:
2 AWG ACSR 4/0 AWG AAC
2/0 AWG ACSR 397 kcmil AAC
1/0 AL EPR 795 kcmil AAC
500 AL EPR
The following, Table 3-4-2, provides conductor economic sizing data based upon
various conductor sizes used on the District’s system for 12.47 kV. This table is
used by first estimating the peak kW load anticipated over the future fifteen-year
period and the construction type (single or three-phase). The conductor size and
approximate thermal capacity may be found in the adjacent columns.
Anticipated Peak kW
@ 12.47 kV Phase Capacity in MW
@ 12.47 kV
Select Minimum
Conductor Size
0-600 1 1.3 2 AWG ACSR
0-800 3 3.9 2 AWG ACSR
--- 3 6.3 2/0 AWG ACSR
600-1,500 3 8.2 4/0 AWG AAC
1,400-6,300 3 12.4 397 kcmil AAC
6,300+ 3 20.0 795 kcmil AAC
0-1,300 1 1.1 1/0 AL EPR
1,300-3,600 3 3.3 1/0 AL EPR
3,600+ 3 8.0 500 AL EPR
Note: The following assumed values were used: · Present Worth Interest (%) = 4.15
· Demand Charge ($/kW/Yr) = 0 · Number of Years in Study = 15
· Energy Charge (mills/kWh) = 71 · Power Factor (%) = 98
· Power Cost Inflation Rate (%) = 4 · Load Factor (%) = 68.39
· Demand Adjustment Factor (%) =70.93 · L-L Voltage in kV = 12.47
· Annual New Carrying Charge (%) = 18.36 · Conductor at 75°C, air at 25°C, wind at 1.4
miles
Economic Conductor Selection 12.47 kV and Peak Loads
Table 3-4-2
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 3.0
3-8
3.5 Power Factor & Losses
Power factor correction to 97.5% lead to lag or better at the delivery points is desired in all
service areas of the system. Consideration should also be given to the installation and
optimum location of shunt capacitors on distribution lines. Capacitors provide a relatively
low cost means to boost voltage and improve and control power factor. These
improvements usually result in some demand reductions, energy conservation, and lower
power costs. Some voltage regulation can be achieved with the judicious sizing and
locating of (usually switched) capacitor banks.
Transformer and voltage regulator losses should be evaluated as a component of purchase
for new equipment.
3.6 Contingency System Conditions
Contingency conditions to be reviewed in this plan include loss of a single substation
transformer, as well as feeder loss on a case-by-case basis.
3.7 Mechanical Condition and Reliability Criteria
The criteria described within this section must be considered in the analysis in order to
provide complete evaluation of the system. Often plans overlook the needs of the present
system and leave physically deteriorated facilities in place. In addition, several operational
concerns can be addressed through the careful evaluation of these constraints with outage
concerns and age of facilities. Specific mechanical items include, but are not limited to, the
following:
a. Distribution lines are to be rebuilt and/or relocated if found to be unsafe or
in violation (when constructed) of the General Orders 95 and 128 or
applicable codes and regulations.
b. Poles and/or cross arms are to be replaced if found to be physically
deteriorated by visual inspection and/or tests (ordinary replacements).
c. Conductors (and associated poles and hardware, as required) shall be
considered for replacement if found to contain an average of over two (2)
splice(s) per phase per span in any one (1) mile increment, or if the
conductor is old, in poor condition, or has been annealed.
System improvements should be considered and made, if necessary, in specific areas where
members have experienced more than one customer hour for suburban and five customer
hours for rural outage hours per year, excluding outages caused by major storms or the
power supplier, for the last five consecutive years.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 4.0
4-1
4.0 PROTECTION PHILOSOPHY
4.1 Basic Principles of System Coordination
The following basic principles of system coordination were considered in development of
the District’s Protection Philosophy:
a. The basic purpose of a distribution system protection scheme is to provide
protection for system equipment, as well as ensure safety of the public in the event
of a fault.
b. The distribution protection scheme is designed to quickly provide restoration of
service to as many consumers as possible. In designing the protection scheme, it is
understood that cost, practicality and service reliability must be viewed as a whole,
with the optimum combination of these three considerations determined by
judgment of the Engineer.
c. Protective devices should correctly and specifically isolate faults so that operations
personnel can easily locate the faulted section, make repairs, and restore service to
consumers.
d. Locations for proposed protective coordination devices, where supplied by the
Engineer, should be field verified by operations personnel. The actual location for
installation must meet protection requirements, as well as provide reasonable access
for operations crews.
e. A final objective of protective coordination is to minimize short circuit stress on
system equipment, in particular, power transformers.
4.2 Sectionalizers
A description of the philosophy used in recommending the use of sectionalizers is as
follows:
a. Modern “cutout style” sectionalizers are preferred over oil-filled sectionalizers to
provide superior visual indication of open line sections.
b. The application of sectionalizers on major overhead line sections where fuses are
unsuitable due to the nature of the load or high incidence of momentary faults
caused by lightning or line contact with trees is encouraged.
c. Sectionalizers are not normally used to isolate URD lines, except where the
underground line feeds a downstream section of overhead distribution, or where the
URD meets the following requirements:
i. The URD feeder is of sufficient length to justify multiple in-series
sectionalizers.
ii. URD of questionable reliability is installed downstream from newer
URD cable.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 4.0
4-2
iii. The number of consumers or other characteristics of the feeder require
multiple in-series sectionalizers to provide service reliability.
iv. Sections of URD which are inaccessible during certain periods of the
year, or otherwise present difficult operations and maintenance
requirements.
v. Load levels prevent use of properly sized fuses.
vi. Where lightning will cause false trip of fuses.
4.3 Fuses
The suitability of overhead line fuses for protection of the cooperative’s distribution system
is evaluated upon the following criteria:
a. Distribution systems in areas of high isokeraunic level, where lines are not shielded
by trees or surrounding terrain, require field experience to optimize the application
of overhead line fuses. In general, limiting fuses to as few locations as possible,
which are easily accessible to operations personnel, will result in optimum service
reliability.
b. Use of overhead line fuses in areas of high isokeraunic level, where trees provide
shielding or adjacent terrain, will be effective if momentary contact of trees with
lines is infrequent.
c. In areas of low isokeraunic activity, overhead line fuses provide an excellent means
of isolating faults, if momentary contact of trees with power lines is infrequent.
d. All URD taps should be fused and properly coordinated with upstream reclosers,
except where sectionalizers are used for fault isolation. Load conditions may cause
a need for VFI device types.
e. Fuses used for protection of taps fed from main trunk lines are recommended to be
coordinated with upstream reclosers as follows:
i. Fuses on URD taps are sized to blow before the upstream recloser
operates on its fast curve, provided that fuses can be adequately sized
for the necessary load current.
ii. Fuse protection of overhead lines connected to main trunk feeders are
coordinated such that they blow before the upstream recloser operates
on its fast curve only if the probability of momentary line faults due to
lightning or trees is very unlikely.
iii. For all other overhead line fuses, coordination results in blown fuses
between fast and slow curves of the upstream recloser, provided that
adequate current carrying capacity is provided.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 4.0
4-3
4.4 Electronic Recloser Applications
Electronically controlled reclosers are recommended for substation feeders serving
predominantly urban or semi-urban areas where load currents are relatively significant or
where fault levels are high and additional coordination intervals can be justified. The
selection between electronically controlled single or three-phase reclosers can be difficult
at times. Single-phase installations trip the phase on which the fault is located, allowing
service to continue to more members, but are more limited in application as loads approach
120 - 150 amps on 7.2/12.47 kV systems. At these load levels, single-phase device pickup
settings may not be adequate for minimum fault levels. Three-phase devices are available,
which allow single-phase tripping-single-phase lockout, single-phase tripping-three-phase
lockout, and three-phase tripping three-phase lockout. Use of three-phase devices allows
lower minimum faults to be picked up while allowing larger load currents. Three-phase
devices use separate phase and ground settings and are not limited in this application.
Generally, the sectionalizing scheme becomes more complicated as load levels increase,
lending more desirability to three-phase devices. Most taps would generally be protected
with a device, leaving three-phase line sections protected by the substation recloser.
The following applications specifically lend themselves to the use of three-phase reclosers:
a. Three-phase reclosers are recommended for feeders serving either urban or rural
areas with predominantly three-phase loads and feeders serving one or more critical
three-phase load(s) where it is undesirable for operations to result in single-phase
service conditions. Examples of such areas include areas with large irrigation
pumps, small and large commercial services, as well as other special load
categories.
b. Three-phase reclosers are strongly recommended for areas with long URD feeders
with ferro-resonant potential. Ferro-resonance is an inductive-capacitive “tuned”
circuit that can result in extremely high voltages and catastrophic failure of
equipment.
4.5 Safety Considerations
The following application criteria were considered to provide a degree of safety to District
personnel as well as to the general public in preparation of this study:
a. Interrupt rating for protective devices must meet or exceed maximum anticipated
fault MVA at the point of application, including a margin for asymmetrical
components for any system operating condition.
b. The distribution protective coordination must detect and isolate minimum fault
currents using conservative values of fault resistance as suggested by RUS in
Bulletin 61-2.
Protective equipment should provide “one-shot” capability for protection of maintenance
personnel when working near energized facilities or lines.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 4.0
4-4
4.6 Guide to Performed Calculations
In the application of overcurrent protective devices for distribution systems, the Engineer
must have knowledge of short duration currents that flow under fault conditions at various
locations on the system. These provide the “Guide to Performed Calculations” in the
analysis. At each recloser location, maximum fault current levels are computed to evaluate
equipment interrupting ratings and coordination. In a radial system, maximum current
through a device occurs for a bolted fault at the device terminals. Minimum values of fault
current are also needed to determine the applicable zone of protection for protective
devices. If the upstream recloser or fuse cannot detect minimum fault levels, either a new
zone of protection must be established, or device settings must be changed to provide
detection of these minimum currents. Minimum fault currents are established by inserting
an impedance of specified value into the fault path. Analytical analysis in the application
of protective devices included:
a. Source Impedance Data obtained from the power supplier for each delivery point.
b. Conductor Size - Maximum fault calculations were based upon conductor size and
computer models provided by TDPUD. Minimum phase-to-ground fault levels
were based on the projected system as presented in the work plan with fault
resistance for overhead lines (40 ohms).
c. Load currents were also addressed in the study. Reclosers, fuses and sectionalizers
each have a continuous current rating. Equipment ratings were compared to the
most recent load data. In general, a hydraulic recloser will be changed out if load
currents exceed 80% of the continuous current rating.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-5
5.0 HISTORICAL DATA & LOAD FORECAST
5.1 Description of Service Area
Truckee Donner Public Utility District (the District), headquartered in Truckee, California,
is located in northeast California. The District’s service area served approximately 13,723
electric customers at the end of 2018.
5.2 Power Supply
The District receives its power from Utah Associated Municipal Power Systems and
Western Area Power Administration through four distribution substations. This power is
wheeled over NV Energy's transmission system.
I. Energy Efficiency and Conservation
When acquiring a new resource, energy efficiency and conservation are considered
the first resource. The District complies with California’s renewable energy, public
benefit, and energy efficiency requirements. As part of the California Energy
Commission’s (CEC) energy efficiency goal setting requirements, the District
adopted the following goals in 2007 for reducing electricity usage:
· Average Annual Feasible Energy (MWH) Target: 0.59% per year over 10 years
· Average Annual Feasible Demand (MW) Target: 0.28% per year over 10 years
· In addition, the District’s Board passed a resolution setting an internal energy goal
of 1% per year over 10 years
Since setting these goals, the District has invested heavily in cost-effective energy
efficiency programs both internally and with their customers.
5.3 Transmission
The District owns a few spans of transmission line from their Donner Lake Substation to
NV Energy's transmission line.
5.4 Connection Statistics & Growth Patterns
Statistics were compiled and visual aids prepared to show connection statistics and growth
trends for the District. These statistics were compared to results of the most recent Power
Requirements Plan to assure that all projections in the plan were consistent. In 2008 The
District reclassified a significant number of customers, and due to that, the trend plots
changed significantly. The trend plots are shown from 2008 on in order to properly depict
growth. Figure 5-4-15 which is included at the end of this section shows the total number
of connections from 1998 to 2018; the District has had a 1.49% increase in connections,
annually since 1998.
The District had a non-coincidental peak of 38.1 MW in December of 2015 and had a total
of 13,388 connections for the year 2015 resulting in an average of 2.84 kW per connection.
Although the District has grown to serve 13,723 customers in 2018, the non-coincidental
peak for 2018 is lower than in 2015. This is most likely due to higher efficiency appliances
and equipment being used by customers. The District has a projected fifteen (15) year peak
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-6
of approximately 48,862 kW and 17,759 total projected connections for the year 2035
resulting in an average 2.75 kW per connection.
Residential
The number of residential connections has increased 1.47% per year over the last
21 years. This growth trend is expected to taper off. Residential monthly average
usage per connection has varied over the last 21 years from 607 kWH in 1999 and
down to 523 kWH in 2003. Usage is expected to remain at approximately 554 kWH
per month.
Figures 5-4-1 and 5-4-2, included at the end of this section, shows residential
consumer statistics, historical usage, as well as a linear regression model projection.
The usage regression shows a 1.11% compounded growth rate. However, over the
last five years, TDPUD has had almost no increase in residential customers.
Small Commercial (< 50 kW)
Commercial connections (< 50 kW), or small commercial connections, grew at an
average growth rate of 1.23% per year over the past 21 years, with average
connection usage at about 1,598 kWH per month. Within the past 10 years, the
number of connections has plateaued with an average growth rate of 0.22% over
the next 15 years. The District anticipates a growth rate of 1.0% for these
connections. Small commercial connection statistics, historical usage, as well as a
linear regression model projection are shown in Figures 5-4-3 and 5-4-4 at the end
of this section.
Medium Commercial (> 50 kW and < 200 kW)
Commercial connections (> 50 kW and < 200 kW) are classified as medium
commercial connections. The number of annual connections has decreased from a
high of 50 connections in 2004 and to 41 connections in 2018. The District
anticipates a growth rate of 0.5% for these connections over the next 15 years.
Medium commercial connection statistics, historical usage, as well as a linear
regression model are shown in Figure 5-4-5 and 5-4-6 at the end of this section. The
linear regression line shows a decrease in future years, but it is expected that the
number of connections will plateau at 41 consumers.
Large Commercial (> 200 kW)
Commercial connections (> 200 kW) are classified as large commercial
connections. The number of annual connections has stayed constant at 5
connections in the last 10 years. It is expected that the growth rate of 0.0% over the
past 21 years will remain the same. The monthly usage per connection has
decreased by 1.81% in the past 10 years. This trend is expected to plateau with
roughly 3-5 customers within the next 15 years. Large commercial connection
statistics, historical usage, as well as a linear regression model are shown in Figure
5-4-7 and 5-4-8 at the end of this section.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-7
Public Authority
The number of public authority connections has increased from 32 in 2007 to 220
in 2018. The increasing number of connections has increased the total usage by
almost 40% in the past ten (10) years. It is expected that the number of connections
and usage will plateau at roughly 223 customers. Public authority statistics and
historical usage are shown in Figure 5-4-9 and 5-4-10 at the end of this section.
Water Pump
The number of water pump connections has plateaued with the growth rate of
0.67% in the last ten (10) years. Pumps belonging to the District's Water
Department make the vast majority of these connections. The number of
connections is expected to stay at 49 per year. Water pump connections and
historical usage are shown in Figures 5-4-11 and 5-4-12 at the end of this section.
The District Use
The District’s usage has increased by 3.56% in the last ten (10) years. The usage is
expected to remain the same at approximately 41,000 kWH/month until late 2020,
when the addition of the Solar Awning Project will begin. District usage is then
expected to decrease by approximately 3,000 kWH/month (36,000 kWH annually).
The District’s usage and historical usage are shown in Figure 5-4-13 and 5-4-14 at
the end of this section.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-8
Figure 5-4-1
Figure 5-4-2
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-9
Figure 5-4-3
Figure 5-4-4
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
10
Figure 5-4-5
Figure 5-4-6
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
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11
Figure 5-4-7
Figure 5-4-8
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
12
Figure 5-4-9
Figure 5-4-10
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
13
Figure 5-4-11
Figure 5-4-12
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
14
Figure 5-4-13
Figure 5-4-14
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
15
Figure 5-4-15
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
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5.5 Line Statistics
As of 2018, the District’s system consisted of approximately 136.07 miles of overhead line
and 87.86 miles of URD. A summary of the construction types are provided in Table 5-5-
1. The service area operates at 12.47 kV. There are approximately 13,723 active services,
for a density of 61.28 consumers per mile of line. A little over half of the conductors on
the system are 3-phase.
Construction Type Miles of Line
Overhead Line:
Single-Phase
Two-Phase
Three-Phase
68.18
5.94
61.95
Underground Line:
Single-Phase
Two-Phase
34.46
2.19
Three-Phase 51.20
TOTAL MILES: 223.93
Truckee Donner Public Utility District
Approximate Distribution System Plant as of 2018
Table 5-5-1
The existing system is a composite of conductor types, as is indicated by the tables on the
following pages. Table 5-5-2 lists conductor miles by size and type for the system and
Table 5-5-3 lists conductor miles by size and type for each substation. Table 5-5-4 displays
the total line miles of the existing underground by size and type.
Conductor Type Three Phase Two Phase Single Phase Total
Table 5-5-2
Truckee Donner PUD - Total Line Miles
1/0 ACSR OH 1.39 0.00 0.00 1.39
1/0 AL UG 25.97 1.33 24.37 51.68
2 ACSR OH 7.30 5.27 66.47 79.03
2 AL UG 2.68 0.85 9.11 12.64
2/0 ACSR OH 30.31 0.00 1.10 31.41
2/0 AL UG 0.77 0.00 0.39 1.16
2/0 CU UG 0.00 0.00 0.25 0.25
336 ACSR OH 1.29 0.00 0.00 1.29
397 AAC OH 13.77 0.00 0.00 13.77
4 CU OH 0.00 0.63 0.00 0.63
4/0 AAC OH 0.41 0.00 0.00 0.41
4/0 ACSR OH 3.39 0.00 0.19 3.58
500 AL UG 19.88 0.00 0.09 19.97
750 AL UG 1.89 0.00 0.00 1.89
795 AAC OH 2.33 0.00 0.00 2.33
AL Bus OH 0.68 0.00 0.01 0.69
CU Bus OH 1.09 0.04 0.37 1.50
UNK SEC OH 0.00 0.00 0.05 0.05
UNK SEC UG 0.00 0.00 0.25 0.25
Totals 113.16 8.13 102.64 223.93
Summary for the TDPUD Area
Page 1 of 1
Substation Conductor Type
Three Phase Two Phase Single Phase Total
Table 5-5-3
Truckee Donner PUD - Total Line Miles
1-Donner Lake
1/0 ACSR OH 0.17 0.00 0.00 0.17
1/0 AL UG 2.56 0.00 2.17 4.72
2 ACSR OH 0.94 0.59 17.44 18.97
2 AL UG 0.34 0.07 2.16 2.57
2/0 ACSR OH 10.24 0.00 0.05 10.29
397 AAC OH 2.43 0.00 0.00 2.43
4/0 AAC OH 0.20 0.00 0.00 0.20
4/0 ACSR OH 0.57 0.00 0.00 0.57
500 AL UG 1.04 0.00 0.00 1.04
750 AL UG 0.09 0.00 0.00 0.09
795 AAC OH 2.33 0.00 0.00 2.33
AL Bus OH 0.11 0.00 0.00 0.11
CU Bus OH 0.02 0.00 0.01 0.03
Summary for 1-Donner Lake
Totals 21.04 0.66 21.83 43.53
2-Tahoe Donner
1/0 AL UG 1.47 0.00 1.89 3.36
2 ACSR OH 0.40 0.42 26.12 26.94
2 AL UG 0.23 0.00 0.69 0.92
2/0 ACSR OH 12.17 0.00 0.05 12.22
2/0 AL UG 0.00 0.00 0.03 0.03
397 AAC OH 0.63 0.00 0.00 0.63
500 AL UG 0.09 0.00 0.00 0.09
750 AL UG 0.43 0.00 0.00 0.43
AL Bus OH 0.10 0.00 0.00 0.10
CU Bus OH 0.00 0.00 0.03 0.04
Summary for 2-Tahoe Donner
Totals 15.53 0.42 28.81 44.76
Page 1 of 3
Substation Conductor Type
Three Phase Two Phase Single Phase Total
Table 5-5-3
Truckee Donner PUD - Total Line Miles
3-Truckee
1/0 ACSR OH 1.22 0.00 0.00 1.22
1/0 AL UG 16.59 0.00 16.34 32.93
2 ACSR OH 2.11 0.72 15.54 18.36
2 AL UG 0.98 0.00 3.73 4.71
2/0 ACSR OH 3.21 0.00 0.83 4.03
2/0 AL UG 0.08 0.00 0.34 0.42
2/0 CU UG 0.00 0.00 0.11 0.11
336 ACSR OH 1.29 0.00 0.00 1.29
397 AAC OH 6.10 0.00 0.00 6.10
4/0 ACSR OH 0.09 0.00 0.05 0.14
500 AL UG 15.28 0.00 0.04 15.32
750 AL UG 0.13 0.00 0.00 0.13
AL Bus OH 0.35 0.00 0.00 0.35
CU Bus OH 0.58 0.00 0.26 0.84
UNK SEC OH 0.00 0.00 0.05 0.05
UNK SEC UG 0.00 0.00 0.25 0.25
Summary for 3-Truckee
Totals 48.01 0.72 37.53 86.25
4-Martis Valley
1/0 AL UG 5.33 0.01 3.98 9.32
2 ACSR OH 0.89 0.03 7.37 8.29
2 AL UG 1.10 0.00 2.53 3.63
2/0 ACSR OH 4.70 0.00 0.17 4.87
2/0 AL UG 0.69 0.00 0.01 0.70
2/0 CU UG 0.00 0.00 0.15 0.15
397 AAC OH 4.60 0.00 0.00 4.60
4/0 AAC OH 0.21 0.00 0.00 0.21
4/0 ACSR OH 2.73 0.00 0.14 2.87
500 AL UG 3.47 0.00 0.05 3.52
750 AL UG 1.25 0.00 0.00 1.25
AL Bus OH 0.12 0.00 0.00 0.12
CU Bus OH 0.48 0.00 0.06 0.54
Summary for 4-Martis Valley
Totals 25.55 0.03 14.47 40.05
Page 2 of 3
Substation Conductor Type
Three Phase Two Phase Single Phase Total
Table 5-5-3
Truckee Donner PUD - Total Line Miles
5-Glenshire
1/0 AL UG 0.02 1.33 0.00 1.35
2 ACSR OH 2.96 3.51 0.00 6.48
2 AL UG 0.04 0.79 0.00 0.82
4 CU OH 0.00 0.63 0.00 0.63
CU Bus OH 0.01 0.04 0.00 0.05
Summary for 5-Glenshire
Totals 3.03 6.30 0.00 9.34
Totals 113.16 8.13 102.64
Summary for the TDPUD Area
223.93
Page 3 of 3
Conductor Type Three Phase Two Phase Single Phase Total
Table 5-5-4
McKenzie Electric Cooperative - Total URD Line Miles
1/0 AL UG 25.97 1.33 24.37 51.68
2 AL UG 2.68 0.85 9.11 12.64
2/0 AL UG 0.77 0.00 0.39 1.16
2/0 CU UG 0.00 0.00 0.25 0.25
500 AL UG 19.88 0.00 0.09 19.97
750 AL UG 1.89 0.00 0.00 1.89
UNK SEC UG 0.00 0.00 0.25 0.25
Totals 51.20 2.19 34.46 87.85
Summary for the TDPUD Area
Friday, July 19, 2019 Page 1 of 1
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
17
5.6 Historical Demand and Growth Patterns
Present substation capacity and peak demand are shown in the Feeder Summary. The
District provides distribution-level voltage through four (4) substations; Donner Lake,
Martis Valley, Tahoe Donner and Truckee. Glenshire Service Area is served off of NV
Energy’s existing 14.4 kV line and does not include a substation.
Figure 5-6-1 shows the growth characteristics of the District’s entire system for the period
1991 through May 2019, as well as projected load growth through year 2035. Figures 5-6-
2 through 5-6-5 display information about past peak demand for each Substation between
2005 and 2019.
Figure 5-6-1
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
18
Figure 5-6-2
Figure 5-6-3
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
19
Figure 5-6-4
Figure 5-6-5
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
20
Figure 5-6-6
During the historical 10 year period that was analyzed, the District has experienced
minimum to little growth in peak demand based on substation peak data from 2004 to 2019.
Since 2006, the average peak demand has plateaued on the District’s system. This can also
be seen by the number of connections in Section 5.4. There was no available data between
June 2008 and December 2008. As such, those values are averages of previous data and
could slightly skew the results.
Having developed a predictor of future average growth, it was then necessary to assign
growth. All areas with potential new development were identified and a growth percentage
was applied to these areas based on the type of development. Since there has been minimum
growth on the system, the only new growth expected during this planning period is new
commercial. Spot loads were added to the existing system to represent this growth.
FEEDER SUMMARYkVAPFkVAPFkVAPFAmperesCustomersLosses kW LossesFeeder1-Donner LakePH0 YR4 YR5 YR0 YR4 YR5 YR0 YR4 YR5 YR0 YR 4 YR 5 YR1-Donner LakeA2019.5B2090.5C2361.6Total6455.192.697.894.995.42037.82121.92394.66537.091.297.093.594.22037.82121.92394.66537.091.297.093.594.248.350.056.548.750.757.348.750.757.37957048332332-369.1393.1-23.60.3-369.1393.1-23.60.3-369.1393.1-23.60.3-6.0%6.4%-0.4%0.0%-6.0%6.4%-0.4%0.0%-6.0%6.4%-0.4%0.0%---------DLR1A459.6B368.4C362.9Total1190.496.897.795.996.9459.6368.4362.91190.496.897.795.996.9459.6368.4362.91190.496.897.795.996.960.848.748.060.848.748.060.848.748.02021911665595.0-12.623.916.45.0-12.623.916.45.0-12.623.916.40.4%-1.1%2.1%1.4%0.4%-1.1%2.1%1.4%0.4%-1.1%2.1%1.4%---------DLR2A491.9B441.9C373.9Total1307.795.796.296.396.0491.9441.9373.91307.795.796.296.396.0491.9441.9373.91307.795.796.296.396.065.158.449.565.158.449.565.158.449.510021424455864.74.34.573.564.74.34.573.564.74.34.573.55.2%0.3%0.4%5.9%5.2%0.3%0.4%5.9%5.2%0.3%0.4%5.9%---------DLR3A1388.9B921.2C1645.5Total3954.994.195.694.494.61388.9921.21645.53954.994.195.694.494.61388.9921.21645.53954.994.195.694.494.6183.7121.9217.7183.7121.9217.7183.7121.9217.7493299423121550.625.061.5137.050.625.061.5137.050.625.061.5137.01.4%0.7%1.6%3.7%1.4%0.7%1.6%3.7%1.4%0.7%1.6%3.7%---------466422722722712307.0Total kW3882.0Total kVAR12904.795.312984.494.712984.494.71.8%1.8%1.8%Substation SummaryTransformer Size102.8103.5103.512307.04139.012307.04139.012/16 MVA 16000 55/65 °CMonday, August 26, 2019Page 1 of 6
FEEDER SUMMARYkVAPFkVAPFkVAPFAmperesCustomersLosses kW LossesFeeder2-Tahoe DonnerPH0 YR4 YR5 YR0 YR4 YR5 YR0 YR4 YR5 YR0 YR 4 YR 5 YR2-Tahoe DonnerA2906.3B2603.1C2578.5Total8074.696.093.597.695.92944.72626.82612.98170.594.892.196.894.72944.72626.82612.98170.594.892.196.894.769.562.261.670.462.862.570.462.862.5817921584232251.8-396.5344.90.351.8-396.5344.90.351.8-396.5344.90.30.7%-5.1%4.5%0.0%0.7%-5.1%4.5%0.0%0.7%-5.1%4.5%0.0%---------TDR1A536.6B402.6C296.0Total1235.294.894.994.994.9536.6402.6296.01235.294.894.994.994.9536.6402.6296.01235.294.894.994.994.971.053.239.171.053.239.171.053.239.1181151744067.65.83.416.87.65.83.416.87.65.83.416.80.6%0.5%0.3%1.4%0.6%0.5%0.3%1.4%0.6%0.5%0.3%1.4%---------TDR2A1012.5B1138.2C977.1Total3127.897.497.297.497.31012.51138.2977.13127.897.497.297.497.31012.51138.2977.13127.897.497.297.497.3134.0150.6129.3134.0150.6129.3134.0150.6129.330236726893744.345.540.5130.244.345.540.5130.244.345.540.5130.21.5%1.5%1.3%4.3%1.5%1.5%1.3%4.3%1.5%1.5%1.3%4.3%---------TDR3A1306.7B1405.1C1001.5Total3713.294.994.595.094.81306.71405.11001.53713.294.994.595.094.81306.71405.11001.53713.294.994.595.094.8172.8185.8132.5172.8185.8132.5172.8185.8132.533340224297737.435.819.993.137.435.819.993.137.435.819.993.11.1%1.0%0.6%2.6%1.1%1.0%0.6%2.6%1.1%1.0%0.6%2.6%---------464224024024015476.0Total kW4591.0Total kVAR16142.695.816235.695.316235.695.31.6%1.6%1.6%Substation SummaryTransformer Size128.6129.4129.415475.04911.015475.04911.0(3) 5/7 MVA 22500 55/65 °CMonday, August 26, 2019Page 2 of 6
FEEDER SUMMARYkVAPFkVAPFkVAPFAmperesCustomersLosses kW LossesFeeder3-TruckeePH0 YR4 YR5 YR0 YR4 YR5 YR0 YR4 YR5 YR0 YR 4 YR 5 YR3-TruckeeA3665.6B3546.6C3604.4Total10815.696.896.797.497.04646.04519.24586.613750.994.594.595.394.86057.85927.95997.317982.393.493.494.093.687.684.886.2111.1108.0109.7144.8141.7143.45906146081812-57.0-98.9156.80.9-58.0-101.1160.71.7-58.3-102.0162.42.1-0.5%-0.9%1.5%0.0%-0.4%-0.8%1.2%0.0%-0.3%-0.6%1.0%0.0%---------TR1A322.6B339.3C461.9Total1123.498.698.497.498.11063.51080.51204.73348.696.396.396.096.22177.52194.22318.06689.795.695.695.495.542.744.861.1140.8142.9159.3288.1290.3306.750471001975.14.95.115.110.29.910.030.115.214.714.544.30.5%0.4%0.5%1.4%0.3%0.3%0.3%0.9%0.2%0.2%0.2%0.7%---------TR2A451.2B200.9C216.6Total867.792.095.694.693.6451.2200.9216.6867.792.095.694.693.6451.2200.9216.6867.792.095.694.693.659.726.628.659.726.628.659.726.628.64223339827.430.5-5.252.727.430.5-5.252.727.430.5-5.252.73.4%3.8%-0.6%6.5%3.4%3.8%-0.6%6.5%3.4%3.8%-0.6%6.5%---------TR3A333.1B228.5C197.0Total758.496.497.297.596.9333.1228.5197.0758.496.497.297.596.9333.1228.5197.0758.496.497.297.596.944.130.226.044.130.226.044.130.226.07844321543.13.22.08.33.13.22.08.33.13.22.08.30.4%0.4%0.3%1.1%0.4%0.4%0.3%1.1%0.4%0.4%0.3%1.1%---------TR4A1483.1B1483.1C1582.6Total4548.897.097.196.997.01631.41631.61731.14994.096.896.996.796.81853.51853.61953.65660.796.696.796.596.6196.3196.2209.4215.9215.8229.0245.3245.3258.415514322352147.344.745.7137.848.746.047.0141.749.446.647.5143.51.1%1.0%1.0%3.1%1.0%1.0%1.0%2.9%0.9%0.9%0.9%2.6%---------TR5A770.6B1000.3C575.2Total2345.297.896.898.297.5770.61000.3575.22345.297.896.898.297.5770.61000.3574.22344.297.896.898.297.5101.9132.376.0101.9132.376.0101.9132.376.021330417469112.731.09.953.512.731.09.953.512.731.09.953.50.6%1.4%0.4%2.3%0.6%1.4%0.4%2.3%0.6%1.4%0.4%2.3%---------Monday, August 26, 2019Page 3 of 6
FEEDER SUMMARYkVAPFkVAPFkVAPFAmperesCustomersLosses kW LossesFeeder3-TruckeePH0 YR4 YR5 YR0 YR4 YR5 YR0 YR4 YR5 YR0 YR 4 YR 5 YRTR6A362.4B380.1C433.2Total1175.697.197.197.097.1362.4380.1433.21175.697.197.197.097.1362.4380.1433.21175.697.197.197.097.148.050.357.348.050.357.348.050.357.35253451508.05.58.421.98.05.58.421.98.05.58.421.90.7%0.5%0.7%1.9%0.7%0.5%0.7%1.9%0.7%0.5%0.7%1.9%---------362331029032620978.0Total kW5258.0Total kVAR21626.997.027219.295.735437.194.91.4%1.2%1.0%Substation SummaryTransformer Size172.3216.9282.426059.07862.033665.011066.0(3) 5/7 MVA 12500 55/65 °CMonday, August 26, 2019Page 4 of 6
FEEDER SUMMARYkVAPFkVAPFkVAPFAmperesCustomersLosses kW LossesFeeder4-Martis ValleyPH0 YR4 YR5 YR0 YR4 YR5 YR0 YR4 YR5 YR0 YR 4 YR 5 YR4-Martis ValleyA3030.6B2804.2C2848.4Total8678.199.799.5100.099.83667.73431.33477.510571.998.598.099.298.64615.84381.44418.813412.397.296.697.997.372.467.068.187.782.083.1110.4104.7105.6679946583220833.5-293.1260.00.334.8-297.7263.50.635.5-299.7265.00.80.4%-3.4%3.0%0.0%0.3%-2.9%2.5%0.0%0.3%-2.3%2.0%0.0%---------MVR1A278.2B341.7C353.1Total972.996.095.795.795.8278.2341.7353.1972.996.095.795.795.8278.2341.7353.1972.996.095.795.795.836.845.246.736.845.246.736.845.246.71832152156132.94.34.511.72.94.34.511.72.94.34.511.70.3%0.5%0.5%1.3%0.3%0.5%0.5%1.3%0.3%0.5%0.5%1.3%---------MVR2A767.2B954.7C752.0Total2474.095.395.195.295.2915.21102.7900.32918.295.295.095.195.11137.51325.01122.33584.895.094.995.095.0101.5126.399.5121.1145.9119.1150.5175.3148.52624552089259.311.79.330.313.816.113.142.916.518.815.450.70.4%0.5%0.4%1.3%0.5%0.6%0.5%1.5%0.5%0.6%0.5%1.5%---------MVR3A794.6B846.6C604.0Total2243.499.799.7-100.099.81112.51165.1918.13195.298.798.899.398.91593.01644.91397.64635.397.497.697.997.6105.1111.979.9147.2154.1121.5210.7217.6184.822821511355629.918.613.461.854.439.430.7124.570.353.342.7166.31.3%0.8%0.6%2.8%1.7%1.2%1.0%3.9%1.6%1.2%0.9%3.7%---------MVR4A1207.4B1020.2C974.5Total3193.6-99.5-97.2-96.5-98.11342.91147.21100.53584.0-99.9-98.7-98.2-99.21550.01347.31298.34191.1100.0-99.7-99.5-99.9159.7134.9128.9177.6151.8145.6205.1178.2171.766147114118.8104.446.0269.1123.7106.648.5278.9126.2107.949.8283.93.8%3.3%1.5%8.6%3.5%3.0%1.4%7.8%3.0%2.6%1.2%6.8%---------441645937351317321.0Total kW1085.0Total kVAR17354.998.621053.398.126624.497.42.2%2.2%2.0%Substation SummaryTransformer Size138.3167.8212.220846.02947.026094.05288.0(3) 5/6.25 MVA 18750 55/65 °CMonday, August 26, 2019Page 5 of 6
FEEDER SUMMARYkVAPFkVAPFkVAPFAmperesCustomersLosses kW LossesFeeder5-GlenshirePH0 YR4 YR5 YR0 YR4 YR5 YR0 YR4 YR5 YR0 YR 4 YR 5 YR5-GlenshireA359.1B467.0C551.4Total1356.889.799.891.895.4359.1467.0551.41356.889.799.891.895.4359.1467.0551.41356.889.799.891.895.441.153.563.141.153.563.141.153.563.11061481834370.00.00.00.00.00.00.00.00.00.00.00.00.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%---------GL1A359.1B467.0C551.4Total1356.889.799.891.895.4359.1467.0551.41356.889.799.891.895.4359.1467.0551.41356.889.799.891.895.441.153.563.141.153.563.141.153.563.1106148183437-59.7193.1-84.049.4-59.7193.1-84.049.4-59.7193.1-84.049.4-4.6%14.9%-6.5%3.8%-4.6%14.9%-6.5%3.8%-4.6%14.9%-6.5%3.8%---------8744949492588.0Total kW816.0Total kVAR2713.695.42713.695.42713.695.41.9%1.9%1.9%Substation SummaryTransformer Size103.6103.6103.62588.0816.02588.0816.0N/A N/A N/A °CMonday, August 26, 2019Page 6 of 6
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
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21
5.7 System Load Factor
Annual load factor is a percentage comparison of a system’s actual kWH purchased versus
the kWH that the system would have purchased if the maximum annual kW demand were
used continuously throughout the year. A high load factor is good for a utility because it
means that the system’s equipment is being fully utilized. Annual variations in kWH usage
are influenced by spring precipitation and by summer and winter temperatures. A mild
winter and wet spring will cause a low load factor because electric residential heating is
reduced.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
22
5.8 Reliability of Electric Service
Outage data was provided for the last five years as shown in Table 5-8-1. Figures 5-8-1
through 5-8-4 describe outage data over the last five years.
Figure 5-8-1
Figure 5-8-2
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
23
Figure 5-8-3
Figure 5-8-4
Outages Minutes Outages Minutes Outages Minutes Outages Minutes Outages Minutes Outages MinutesTransmission3 557811 25 6041127 13 1960323 371 15145056 2 2806463 26 4796384Weather10 243326 7 4162704 4 1956865 76 13726139 23 710830 38 1198754Animals7 142984 8 3363927 28 925218 26 2226219 5 420748 3 886476Switch Operation5 80075 45 1953122 18 868883 43 2041627 2 174478 6 640670Undetermined1 14040 7 580102 17 200957 65 1709586 16 78476 75 585405Human Cause3 7169 1 165207 2 2519 9 1511093 35 57045 15 427579Unknown2 5648 3 118208 0 0 9 307872 17 53646 15 249092Planned Outage3 6 2 105708 0 0 6 154373 1 32080 110 238045Equipment Failure0 0 5 200 0 0 23 75026 12 14460 12 32408Non-Outage0 0 0 0 0 0 1 12479 14 12893 35 31322Vegetation0 0 0 0 0 0 4 431 4 562 2 11177Foreign Interference0 0 0 0 0 0 0 0 1 0 0 0Totals34 1051059 103 16490305 82 5914765 633 36909901 132 4361681 337 9097312TDPUD Outage Data 2014-2019Table 5-8-12014 2015 2016 2017 2018 2019
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
24
5.9 Annual System Demand
Demand is the number of kilowatts being used at an instantaneous point in time. Demand
is averaged over 15-minute intervals. The District’s non-coincident peak demand in
December 2015 was 38.1 MW. Peak demand is based on winter and summer peaks. Table
5-9-1 shows the individual substations and whether they are winter or summer peaking.
Summer peaks usually consists of motor loads for irrigation or air conditioning units, while
winter peaks occur due to an increase in electric heat. Donner Lake Substation’s peak loads
do not have significant jumps between the winter and summer months. Summer peaking
was chosen based on a slightly higher peak loading in 2013, but it is negligible and thus,
either summer or winter peak loads could be used.
Peak Demands Based on Season
Table 5-9-1
Summer Peaking Winter Peaking
Truckee Tahoe Donner
Donner Lake Glenshire
Martis Valley
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 5.0
5-
25
5.10 Status of Previous Master Plan Items
Table 5-10-1 lists 2014 Electric System Master Plan Items with the project status and any
additional remarks.
Status of 2014 Electric System Master Plan Items
Table 5-10-1
Substation
Code
Description
Length
(Miles)
Current Status
of Project
Donner Lake DL-C1 Rebuild 3Æ 2/0 AWG ACSR with 3Æ 397 kcmil AAC .35 Carry-Over (LR)
Donner Lake DL-C2 INSTALL S&C PMH-9, PAD-MTD SWGR, 15KV EQUIP 2 Carry-Over (LR)
Donner Lake DL-C4 Rebuild 3Æ 2/0 AWG ACSR with 3Æ 397 kcmil AAC .77 Carry-Over (LR)
Donner Lake DL-C5 Install 328 Amp, 250 kVA Equipment 3 Carry-Over (LR)
Glenshire GL-01 Install Glenshire Autotransformer Equipment 1 Carry-Over (LR)
Glenshire GL-02 Construct 3Æ 500 MCM 1.9 Completed
Martis Valley MV-C1 Rebuild 3Æ 350 EPR with 3Æ 750 EPR .014 Completed
Martis Valley MV-C2 Rebuild 3Æ 350 EPR with 3Æ 500 MCM .34 Completed
Tahoe Donner TD-01 Construct 3Æ 397 kcmil AAC .89 Completed
Tahoe Donner TD-03 Construct 3Æ 397 kcmil AAC .65 Completed
Tahoe Donner TD-C1 Rebuild 3Æ 500 EPR with 3Æ 750 EPR .12 Completed
Tahoe Donner TD-C2 Rebuild 3Æ 4/0 AWG ACSR with 3Æ 397 kcmil AAC .8 Carry-Over (LR)
Tahoe Donner TD-C3 Rebuild 3Æ 4/0 AWG ACSR with 3Æ 397 kcmil AAC .86 Carry-Over (LR)
Truckee TR-C1 Rebuild 3Æ 2 AWG ACSR with 3Æ 4/0 AWG ACSR .33 Carry-Over (LR)
Truckee TR-C2 Rebuild 3Æ 4/0 AWG ACSR with 3Æ 397 kcmil AAC .59 Carry-Over (LR)
Truckee TR-C3 Rebuild 3Æ 350 Al EPR with 3Æ 750 MCM .15 Carry-Over (LR)
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-1
6.0 CONSTRUCTION RECOMMENDATIONS
This section discusses the analysis of the existing distribution system by substation,
projected loading on the existing system, and substation changes and distribution system
improvements required over the next 15 years. MilsoftTM reports showing results of the
regulated load flows for the existing system and projected 5, 10 and 15-year system are
included in each section. Voltage drop, loading and capacity, power factor, losses,
conditions of plant, and service reliability are discussed for the present system with existing
and projected loading. These results can also be found on the accompanying flash drive,
along with the system model.
a. Loading and Capacity
This section details the substation, number of transformers, service bays, etc. Any
equipment overloading is listed in this section
b. Mechanical Condition of Plant
This section details each service area’s unique electrical performance and
characteristics.
c. System Analysis
This section provides individual feeder information and recommended projects in
order to improve the feeder to planning criteria. Also included are the total costs
for the recommended projects.
d. Contingency System Planning
This section of the report provides various summaries to show system performance
with the loss of a single substation transformer and various feeder contingencies.
Several of the reports utilized for the normal system may be reproduced for the
system contingency.
e. Sectionalizing Recommendations
This section of the report provides various summaries to show system performance
with the loss of a single substation transformer and various feeder contingencies.
Several of the reports utilized for the normal system may be reproduced for the
system contingency.
The table below summarizes the two main types of hydraulic reclosers (Type E and
H) on the District’s system and the recommended Kearney T fuse sizes to be placed
downline from the reclosers. In the case of a maximum three-phase bolted fault, a
fuse may melt even if it is classified in the fuse-saving column.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-2
Size
Type Fuse
Saving
Non-
Fuse
Saving
Type Fuse
Saving
Non-
Fuse
Saving
E T T H T T
50
2A2B 15 6 2A2B 15 6
2A2C 25 6 2A2C 20 6
35
2A2B 12 3 2A2B 12 3
2A2C 15 3 2A2C 15 3
25
2A2B 8 3 2A2B 8 3
2A2C 12 3 2A2C 12 3
15
2A2B 6 N/A 2A2B 6 N/A
2A2C 8 N/A 2A2C 8 N/A
10
2A2B 3 N/A 2A2B 3 N/A
2A2C 6 N/A 2A2C 3 N/A
5
2A2B 3 N/A 2A2B 3 N/A
2A2C 3 N/A 2A2C 3 N/A
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-3
6.1 DONNER LAKE SERVICE AREA
The Donner Lake Service Area has a projected growth rate of 0.85%1, with losses
compounded annually for the plan period. This service area serves consumers in the
western area of TDPUD’s system, which includes consumers to the west and south of
Donner Lake, with service to approximately 3,619 customers and a total load of 7.9 MW.
There are existing 3-phase ties between TD-1 and DL-3, TR-4 and DL-1 and MV-3 and
DL-1.
a. Loading and Capacity
Donner Lake Substation has two (2) three-phase 12/16/20 MVA 60/12.47 kV
transformers, three (3) distribution bays in service and 667 kVA, 875 amp
regulators. One transformer is currently a spare. The substation transformer loading
is at 50.4% with 15-year loads.
b. Mechanical Condition of Plant
There are no deficiencies noted for Donner Lake Service Area.
c. System Analysis
i. DL-1 CIRCUIT
Feeder DL-1 serves the area to the east of the Donner Lake Substation,
where it then wraps around Donner Lake to tie to Feeder DL-2. There is
approximately 1.7 MW of load on this feeder. No low voltage occurs on
this feeder with existing or future loads.
ii. DL-2 CIRCUIT
Feeder DL-2 serves the area to the south of the Donner Lake Substation,
where it serves the customers to the west and south side of Donner Lake.
There is approximately 1.7 MW of load on this feeder. No low voltage
occurs on this feeder with existing or future loads.
iii. DL-3 CIRCUIT
Feeder DL-3 extends to the north of the Donner Lake Substation, and serves
as a tie point to Tahoe Donner Substation’s Feeder TD-1. There is
approximately 4.5 MW of load on this feeder. No low voltage occurs on this
feeder with existing or future loads.
1 Load growth was calculated from 02/2016 to present due to skewed results when including 2015 historical values, during which
a load transfer from TD-1 occurred.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-4
Project DL-01 This portion of the line has over 30 amps on a single phase.
It is recommended to rebuild approximately 0.46 miles of
single-phase 2 AWG ACSR with three-phase 2 AWG
ACSR. This line starts west of the intersection of
Northwoods Blvd and Davos Drive, where it follows
Skislope Way north.
Estimated Cost: $ 117,300
Project DL-02 This portion of the line has over 36 amps on a single phase.
It is recommended to rebuild approximately 0.1 miles of
single-phase 2 AWG ACSR with three-phase 2 AWG ACSR
from the R30 recloser to the west intersection of Hillside Dr.
and Gyrfalcon St. and upgrade the R30 recloser to three
single-phase reclosers.
Estimated Cost: $ 25,000
d. Phase Balancing Projects
· Move OHP_3806 from A-phase to B-phase
· Move OHP_73472 from C-phase to B-phase
e. Contingency Options
In the event of the loss of a substation transformer, the following devices are
recommended to be switched:
Close switch A59
Close switch A36
Close recloser R-10
Portions of Martis Valley Feeder 3 are overloaded at 15-year peak loading levels
including OHP_4321-S1958 to OHP_4321-S1100, OHP_81233 to OHP_81887-
S6936 and OHP_21923-S2589 to OHP_21923.
Minimum Voltages On Donner Lake Service Area During Contingency
Existing 5-year 15-year
A 111.9 110.4 108.0
B 112.8 111.3 109.1
C 113.4 112.0 109.9
Tahoe Donner Transformer Loading 59.3% 59.3% 59.3%
Tahoe Donner Regulator Loading 65.9% 65.9% 65.9%
Martis Valley Transformer Loading 62.0% 71.7% 86.4%
Martis Valley Regulator Loading 61.5% 71.1% 85.7%
Table 6.1-1
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-5
i. DL-1 Feeder
DL-1 has one (1) tie to Martis Valley MV-3 feeder (recloser 169.451/switch
166.1675) and a 2-phase tie to Truckee TR-4 feeder as well as a tie to DL-
2. Instead of feeding from Truckee or Martis Valley substations, it is
recommended to tie DL-1 to Tahoe Donner Substation. This substation is
the closest to the tie point.
There is low voltage of 111.7V on DL-1 along the north side of Donner
Lake at 15-year peak loading levels.
Project DL-C1 It is recommended to rebuild approximately 0.35 miles of
2/0 AWG ACSR with 397 kcmil AAC. This will improve
voltage at the end of the line during load transfer and
improve conductor loading. This line starts west of the
intersection of Northwoods Blvd and Donner Pass Road,
where it follows Donner Pass Road for approximately 690
feet before turning south to Deerfield Drive.
Estimated Cost: $ 99,000
ii. DL-2 Feeder
DL-2 has no existing ties to any adjacent substations. It has two (2) ties to
DL-1. In order to transfer the entire feeder to DL-1, it is possible to close
either of the existing switches or as recommended below, a new tie could
be built between DL-3 and DL-2 at the substation.
There is low voltage of 112.0V on DL-2 along the west side of Donner Lake
at existing peak loading levels and low voltage of 108.0V at 15-year peak
loading levels.
Project DL-C2 This substation has URD feeder getaways. It is
recommended that switches be installed to tie feeders DL-2
and DL-3 together. Two switchgear units, such as S&C 330,
could be installed with a URD cable connecting the
switchgear using one bay in each to tie the feeders together.
Estimated Cost: $ 75,000
Project DL-C4 It is recommended to rebuild approximately 0.77 miles of
existing 2/0 AWG ACSR to 397 kcmil AAC between the
intersection of Donner Pass Road and Donner Lake Rd to the
intersection of S Shore Dr and Maple St. This will improve
voltage to the end of the line.
Estimated Cost: $ 218,000
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-6
Project DL-C5 It is recommended to install a bank of 328 amp, 250 kVA
regulators near the Crossroads Shopping Center.
Estimated Cost: $ 60,000
Project DL-C6 It is recommended to rebuild approximately 0.8 miles of
existing 2/0 AWG ACSR to 397 kcmil AAC from S108 to
A59. This line is loaded to 140% with existing loading levels
when Tahoe Donner is transferred to Donner Lake.
Estimated Cost: $ 223,000
iii. DL-3 Feeder
DL-3 has one (1) tie to Tahoe Donner TD-1 feeder (switch A-59).
There is no low voltage or conductor overloading during load transfer with
existing or future loads.
f. Sectionalizing Recommendations
Donner Lake Substation has one (1) 12/16 MVA 60-7.2/12.47 kV distribution
transformer, with SEL-587 relays for differential protection.
The following recommendations are made for the Donner Lake Substation:
a) Substation relay protection
New relay settings are shown at the end of this section. It is recommended
to disable all negative sequence protection settings, and disable all EM Reset
settings.
b) Feeder Recloser
New relay settings are shown at the end of this section.
Voltage Highside Protection Transformer Size % Impedance
Donner Lake 60 kV SEL-587 (1) 12/16 MVA 7.80
The following table shows the fault location impedances for the existing electronic
reclosers existing on Donner Lake Substation. These impedance values are used on
the Form 6’s to locate faults on the line by calculating the approximate distance
from the recloser based on impedance data from the fault. Though these will not
give exact locations of the fault, it will help to narrow down certain areas the fault
may have occurred, making it easier for fault locating.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-7
Substation Recloser R X R0 X0 Miles
Donner Lake
DL-1 0.94 2.98 2.22 5.29 2.86
DL-2 1.61 2.89 2.85 5.20 2.25
DL-3 0.35 2.70 0.68 4.64 2.35
Due to Donner Lake Substation being rebuilt, new settings will be provided by ECI.
Any recommendations provided herein for Donner Lake Substation are temporary
settings until the completion of the rebuild. The following equipment is
recommended for removal or installation on Donner Lake Substation:
i. DL-1 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 8.9 miles of primary line on this circuit, with a
majority of the line being overhead conductor. There are fuses protecting
branch circuits on this feeder and an open recloser between DL-1 and MV-
3.
The following recommendations are made for this feeder:
a. Feeder Recloser
It is recommended to disable the high-current trip settings and change the
phase and ground fast curves. Refer to the settings sheet at the end of the
section.
ii. DL-2 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 8.15 miles of primary line on this circuit, with a
majority of the line being overhead conductor. There are fuses protecting
branch circuits on this feeder.
a. Feeder Recloser
It is recommended to disable the high-current trip settings and increase
pickup settings. Refer to the settings sheet at the end of the section.
iii. DL-3 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 26.43 miles of primary line on this circuit, with a
majority of the line being overhead conductor. This feeder serves primarily
as a tie point to Tahoe Donner TD-1 Feeder. The district has recently
installed two SPEAR reclosing units on this feeder.
a. Feeder Recloser
It is recommended to change the phase and ground fast curves. Refer to the
settings sheet at the end of the section.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-8
b. Recloser 1R20
It is recommended to replace this recloser with a Spear recloser with Cooper
Form 6 control.
Estimated Cost: $ 15,000
c. Recloser 1R30
It is recommended to replace this recloser with a Spear recloser with Cooper
Form 6 control.
Estimated Cost: $ 15,000
Donner Lake Substation
Fuse Size
T
Device No. Fuse
Saving
Non Fuse
Saving
DL-1 Recloser 50 12
DL-2 Recloser 50 12
DL-3 Recloser 50 12
R10 Recloser 40 8
R20 Recloser 25 8
R30 Recloser 25 8
R50 Recloser 25 8
R65 Alder Recloser 40 8
R90 Recloser 30 10
Current in Amperes1,00010,000100,000Time In Seconds.001
.01
.1
1
10
100
1,000
10,000
179
Minimum Fault
744 A PU U4-US Ext Inv
1488 A PU U4-US Ext Inv
592 A PU U4-US Ext Inv
124 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
200 A PU U4-US Ext Inv
5743
Three Phase Fault
TDPUD 2019 Master Plan 10/21/2019
Donner Lake Coordination 7.2 kV
Current in Amperes1001,00010,000100,000Time In Seconds.001
.01
.1
1
10
100
1,000
10,000
6113
Phase-Ground Fault
179
Minimum Fault
744 A PU U4-US Ext Inv
592 A PU U4-US Ext Inv
1488 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
124 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
200 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
Donner Lake Coordination 7.2 kV
Current in Amperes1,00010,000100,000Time In Seconds.001
.01
.1
1
10
100
1,000
10,000
179
Minimum Fault
4973
Phase-Phase Fault
744 A PU U4-US Ext Inv
592 A PU U4-US Ext Inv
1488 A PU U4-US Ext Inv
124 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
200 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
Donner Lake Coordination 7.2 kV
Current in Amperes10100
1,00010,000Time In Seconds.01
.1
1
10
100
1,000
170 A Amp: Curve--140
330 A Amp: Curve--117
330 A Amp: Curve--103
170 A Amp: Curve--104
1135
R30 Phase-Ground Fault
169
Minimum Fault
130 A Amp: Curve--117
130 A Amp: Curve--106
TDPUD 2019 Master Plan 10/21/2019
DL-3 Coordination 7.2 kV
Current in Amperes10100 1,00010,000Time In Seconds.01
.1
1
10
100
1,000
330 A Amp: Curve--103
170 A Amp: Curve--104
330 A Amp: Curve--117
170 A Amp: Curve--140
170
Minimum Fault
1669
R90 Three Phase Fault
100 A Amp: Curve--106
100 A Amp: Curve--117
140 A Amp: Curve--104
140 A Amp: Curve--135
250 A Amp: Curve--117
995
R50 Phase-Ground Fault
TDPUD 2019 Master Plan 10/21/2019
DL-3 Coordination 7.2 kV
Current in Amperes100
1,00010,000Time In Seconds.01
.1
1
10
100
1,000
330 A Amp: Curve--103
170 A Amp: Curve--140
330 A Amp: Curve--117
170 A Amp: Curve--104
1679
R65 Three Phase Fault 170
Minimum Fault
140 A Amp: Curve--104
250 A Amp: Curve--101
140 A Amp: Curve--135
250 A Amp: Curve--117
TDPUD 2019 Master Plan 10/21/2019
DL-3 Coordination 7.2 kV
Current in Amperes101001,00010,000100,000Time In Seconds.01
.1
1
10
100
1,000
10,000
330 A Amp: Curve--103
330 A Amp: Curve--117
170 A Amp: Curve--140
170 A Amp: Curve--104
179
Minimum Fault
6113
Phase-Ground Fault
1488 A PU U4-US Ext Inv
592 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
200 A PU U4-US Ext Inv
744 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
124 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
Donner Lake Coordination 7.2 kV
Current in Amperes10100
1,00010,000Time In Seconds.01
.1
1
10
100
1,000
330 A Amp: Curve--117
170 A Amp: Curve--140
330 A Amp: Curve--101
170 A Amp: Curve--106
1771
R20 Phase-Ground Fault
175
Minimum Fault
130 A Amp: Curve--117
130 A Amp: Curve--106
TDPUD 2019 Master Plan 10/21/2019
DL-3 Coordination 7.2 kV
Current in Amperes10100 1,00010,000Time In Seconds.01
.1
1
10
173
Minimum Fault
100 A Amp: Curve--135
160 A Amp: Curve--101
100 A Amp: Curve--106
160 A Amp: Curve--117
330 A Amp: Curve--103
170 A Amp: Curve--105
170 A Amp: Curve--135
330 A Amp: Curve--117
2305
R10 Three Phase Fault
TDPUD 2019 Master Plan 10/21/2019
DL-1 Coordination - R10 Alt 1 7.2 kV
Current in Amperes101001,00010,000100,0001,000,000Time In Seconds.001
.01
.1
1
10
100
1,000
10,000
6113
Phase-Ground Fault
179
Minimum Fault
744 A PU U4-US Ext Inv
170 A Amp: Curve--105
330 A Amp: Curve--103
170 A Amp: Curve--135
330 A Amp: Curve--117 592 A PU U4-US Ext Inv
1488 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
124 A PU U4-US Ext Inv
200 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
DL-1 Upline Coordination 7.2 kV
Current in Amperes101001,00010,000100,0001,000,000Time In Seconds.01
.1
1
10
100
1,000
10,000
179
Minimum Fault
6113
Phase-Ground Fault
744 A PU U4-US Ext Inv
170 A Amp: Curve--106
330 A Amp: Curve--101
330 A Amp: Curve--117
170 A Amp: Curve--135
592 A PU U4-US Ext Inv
1488 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
124 A PU U4-US Ext Inv
308 A PU U4-US Ext Inv
200 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
DL-2 Upline Coordination 7.2 kV
Current in Amperes101001,00010,000Time In Seconds.01
.1
1
10
100
1,000
40 -Total Clear
5348
40T Three Phase Fault 178
Minimum Fault
170 A Amp: Curve--135
330 A Amp: Curve--117
330 A Amp: Curve--101
170 A Amp: Curve--106
TDPUD 2019 Master Plan 10/21/2019
DL-2 Coordination 7.2 kV
Current in Amperes10100
1,00010,000Time In Seconds.01
.1
1
10
100
1,000
170 A Amp: Curve--140
330 A Amp: Curve--117
330 A Amp: Curve--103
170 A Amp: Curve--104
169
Minimum Fault 1771
R20 Phase-Ground Fault
130 A Amp: Curve--117
130 A Amp: Curve--106
TDPUD 2019 Master Plan 10/21/2019
DL-3 Coordination 7.2 kV
Substation Donner Lake
Feeder DL-1
Location
Device Form 5
Exis Rec Exis Rec
Min Trip Phase 330
Min Trip Ground 170
TCC1P 101 103
TCC2P 117
TCC3P --
TCC4P --
TCC1G 106 105
TCC2G 135
TCC3G
TCC4G
Oper to LO Phase 4
Oper on TCC1 Phase 2
Oper to LO Gnd 3 4
Oper on TCC1 Gnd 2 2
TCC1P Mult 1
TCC1P Adder 0 0.04
TCC1G Mult 1
TCC1G Adder 0 0.04
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase (ON/OFF) On Off
High-Current Trip Ground (ON/OFF) On Off
High-Current Trip Phase (Trip)15
High-Current Trip Ground (Trip)8.3
High-Current Trip Phase (Trip No.)
High-Current Trip Ground (Trip No.)
High-Current Lockout Phase (ON/OFF)Off
High-Current Lockout Ground (ON/OFF)Off
High-Current Lockout Phase (Trip)4780
High-Current Lockout Ground (Trip)1620
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Substation
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Donner Lake Substation
Feeder DL-2
Location Substation
Device Form 5
Exis Rec Exis Rec
Min Trip Phase 280 330
Min Trip Ground 180 170
TCC1P 101
TCC2P 117
TCC3P --
TCC4P --
TCC1G 106
TCC2G 135
TCC3G
TCC4G
Oper to LO Phase 2
Oper on TCC1 Phase 1
Oper to LO Gnd 2
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0
TCC1G Mult 1
TCC1G Adder 0
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase (ON/OFF) On Off
High-Current Trip Ground (ON/OFF) On Off
High-Current Trip Phase (Trip)14.3
High-Current Trip Ground (Trip)8.33
High-Current Trip Phase (Trip No.)1
High-Current Trip Ground (Trip No.)1
High-Current Lockout Phase (ON/OFF)Off
High-Current Lockout Ground (ON/OFF)Off
High-Current Lockout Phase (Trip)
High-Current Lockout Ground (Trip)
High-Current Lockout Phase (Trip No.)
High-Current Lockout Ground (Trip No.)
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Donner Lake Substation
Feeder DL-3
Location Substation
Device Form 6
Primary Alternate 1
Exis Rec Exis Rec
Min Trip Phase 330
Min Trip Ground 170
TCC1P 101 103
TCC2P 117
TCC3P --
TCC4P --
TCC1G 106 104
TCC2G 140
TCC3G
TCC4G
Oper to LO Phase 2
Oper on TCC1 Phase 1
Oper to LO Gnd 2
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0.03 0.04
TCC1G Mult 1
TCC1G Adder 0.03 0.05
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase (ON/OFF) Off
High-Current Trip Ground (ON/OFF) Off
High-Current Trip Phase (Trip)
High-Current Trip Ground (Trip)
High-Current Trip Phase (Trip No.)
High-Current Trip Ground (Trip No.)
High-Current Lockout Phase (ON/OFF)Off
High-Current Lockout Ground (ON/OFF)Off
High-Current Lockout Phase (Trip)
High-Current Lockout Ground (Trip)
High-Current Lockout Phase (Trip No.)
High-Current Lockout Ground (Trip No.)
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Donner Lake
Feeder Substation High Side
Location
Device SEL-551
Primary
Exis Rec
CTR 40
CTRN 40
50P1P 38.5 OFF
51P1P 7.7
51P1C U4
51P1TD 4
50N1P OFF
51N1P 5
51N1C U4
51N1TD 11
50G1P 31 OFF
51G1P 3.1
51G1C U4
51G1TD 6.6
50Q1P OFF
51Q1P 4.2 OFF
51Q1C U4
51Q1TD 6.6
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Donner Lake
Feeder Substation High Side
Location
Device SEL-587
MVA
VWDG1
VWDG2
CTR1
CTR2
TAP1
TAP2
50P1P
50P1D
50P1H
51P1P
51P1C
51P1TD
50Q1P
50Q1D 5
51Q1P 4.2 OFF
51Q1C U4
51Q1TD 6.6
50N1P OFF 31
50N1D 16000 6
50N1H 31 OFF
51N1P 3.1
51N1C U4
51N1TD 5
50P2P 5.1 31.3
50P2D 10800 6
50P2H 31.3 OFF
51P2P 9.3
51P2C U4
51P2TD 4
50Q2P OFF
50Q2D 16000
51Q2P 5.1 OFF
51Q2C U4
51Q2TD 4
50N2P OFF
50N2D 5
50N2H OFF
51N2P 3.7
51N2C U4
51N2TD 5
4
OFF
38.5 OFF
7.7
U4
4.63
4.2 38.5
10800 6
40
160
3.85
16
60
12.47
Primary
Exis Rec
Substation
Feeder 3
Location R20
Device Cooper SPEAR
Exis Rec
Min Trip 130
TCC1 106
TCC2 117
TTL 4
Oper #1 TCC1
Oper #2 TCC1
Oper #3 TCC2
Oper #4 TCC2
TCC1 Mult 1
TCC1 Adder 0
TCC1 Min Response Time DISABLE
TCC1 HCT DISABLE
TCC1 HCT Time Delay DISABLE
TCC2 Mult 1
TCC2 Adder 0.04
TCC2 Min Response Time DISABLE
TCC2 HCT DISABLE
TCC2 HCT Time Delay DISABLE
Note: Settings in the recommended column that are
the same as the existing settings are not listed unless
otherwise noted.
Donner Lake
Primary
Substation
Feeder 3
Location R30
Device Cooper SPEAR
Exis Rec
Min Trip 130
TCC1 106
TCC2 117
TTL 4
Oper #1 TCC1
Oper #2 TCC1
Oper #3 TCC2
Oper #4 TCC2
TCC1 Mult 1
TCC1 Adder 0
TCC1 Min Response Time DISABLE
TCC1 HCT DISABLE
TCC1 HCT Time Delay DISABLE
TCC2 Mult 1
TCC2 Adder 0.04
TCC2 Min Response Time DISABLE
TCC2 HCT DISABLE
TCC2 HCT Time Delay DISABLE
Note: Settings in the recommended column that are
the same as the existing settings are not listed unless
otherwise noted.
Donner Lake
Primary
Substation
Feeder 3
Location R65 Alder
Device Cooper Form 4
Primary
Exis Rec
Min Trip Phase 250
Min Trip Ground 140
TCC1P 101
TCC1G 104
TCC2P 117
TCC2G 135
Oper to LO Phase 4
Oper on TCC1 Phase 2
Oper to LO Gnd 4
Oper on TCC1 Gnd 2
TCC1P Mult
TCC1P Adder 0.02
TCC1G Mult
TCC1G Adder 0.02
TCC2P Mult
TCC2P Adder
TCC2G Mult
TCC2G Adder
Note: Settings in the recommended column that are
the same as the existing settings are not listed unless
otherwise noted.
Donner Lake
Substation
Feeder 3
Location R90
Device Cooper Form 4
Primary
Exis Rec
Min Trip Phase 250
Min Trip Ground 140
TCC1P 101
TCC1G 104
TCC2P 117
TCC2G 135
Oper to LO Phase 4
Oper on TCC1 Phase 2
Oper to LO Gnd 4
Oper on TCC1 Gnd 2
TCC1P Mult
TCC1P Adder 0.02
TCC1G Mult
TCC1G Adder 0.02
TCC2P Mult
TCC2P Adder
TCC2G Mult
TCC2G Adder
Note: Settings in the recommended column that are
the same as the existing settings are not listed unless
otherwise noted.
Donner Lake
Substation
Feeder 3
Location R50
Device Cooper SPEAR
Primary
Exis Rec
Min Trip 100
TCC1 106
TCC2 117
TTL 4
Oper #1 TCC1
Oper #2 TCC1
Oper #3 TCC2
Oper #4 TCC2
TCC1 Mult 1
TCC1 Adder 0
TCC1 Min Response Time DISABLE
TCC1 HCT DISABLE
TCC1 HCT Time Delay DISABLE
TCC2 Mult 1
TCC2 Adder 0.04
TCC2 Min Response Time DISABLE
TCC2 HCT DISABLE
TCC2 HCT Time Delay DISABLE
Note: Settings in the recommended column that are
the same as the existing settings are not listed unless
otherwise noted.
Donner Lake
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-9
6.1 GLENSHIRE SERVICE AREA
The District takes service from NV Energy’s 14.4 kV line to serve the Glenshire service
area. The Glenshire Service Area has a projected growth rate of 1.78%, with losses
compounded annually for the plan period. It is located on the far eastern portion of the
District’s service territory with service to approximately 485 customers and a total load of
1.3 MW.
a. Loading and Capacity
Glenshire Service Area takes power from NV Energy’s existing 14.4 kV line.
b. Mechanical Condition of Plant
There is approximately 0.63 miles of 4 HdCu, which makes up 6.7% of
Glenshire Service Area.
c. System Analysis
i. GL-1 CIRCUIT
Feeder GL-1 serves the area to the east and south of the primary meter.
There is approximately 1.3 MW of load on this feeder. No low voltage
occurs on this feeder with existing or future loads.
Project GL-01 Within the planning period, TDPUD would like to engineer
and then install a new autotransformer where they are
metered off NV Energy’s existing line in order to create a
three-phase tie with TR-1.
Estimated Cost: $ 850,000
d. Contingency Options
There are no contingency options for Glenshire service area. It is recommended to
install a step-up transformer on Truckee Feeder 1 in order to tie Glenshire to
Truckee. Table 6.2-1 the results of adding a step transformer.
Minimum Voltages On Glenshire Service Area During Contingency
Existing 5-year 15-year
A 121.4 121.2 121.0
B 122.4 122.3 122.1
C 119.6 119.5 119.4
Truckee Transformer Loading 56.6% 69.3% 88.6%
Truckee Regulator Loading 62.9% 76.9% 98.4%
Table 6.2-1
*NC=did not converge
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-10
e. Sectionalizing Recommendations
The following table shows the fault location impedances for the electronic reclosers
located at the meter point. These impedance values are used on the Form 6’s to
locate faults on the line by calculating the approximate distance from the recloser
based on impedance data from the fault. Though these will not give exact locations
of the fault, it will help to narrow down certain areas the fault may have occurred,
making it easier for fault locating.
Substation Recloser R X R0 X0 Miles
Glenshire GL-1 1.69 1.05 2.54 2.89 1.20
SPPC 0.11 0.07 0.16 0.16 0.18
i. GL-1 Feeder
This feeder is protected by a WE recloser with Cooper Form 6 control.
There are approximately 9.34 miles of primary line on this circuit, with a
majority of the line being overhead conductor.
There are no recommendations made for this feeder.
ii. GL-1 SPPC Feeder
This feeder is protected by a WVE recloser with Cooper Form 6 control.
There are approximately 410 feet of line on this circuit, with a majority of
the line being overhead conductor.
There are no recommendations made for this feeder.
Glenshire Service Area
Fuse Size
T
Device No. Fuse
Saving
Non Fuse
Saving
GL-1 Recloser 65 8
SPPC GL-1 Recloser 65 8
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-11
6.2 MARTIS VALLEY SERVICE AREA
The Martis Valley Service Area has a projected growth rate of 2.21%2, with losses
compounded annually for the plan period. This service area serves rural and urban
residential, commercial and industrial consumers in the southern portion of TDPUD’s
service area. This substation serves approximately 2,526 customers with a total load of 8.7
MW. There is an existing 3-phase tie between TR-1 and MV-4, two separate ties between
TR-2 and MV-3, two between TR-3 and MV-3, one between TR-4 and MV-3 and one
between DL-1 and MV-3.
a. Loading and Capacity
Martis Valley Substation has three (3) 5/6.25 MVA 120/13.2 kV transformers and
four (4) distribution bays in service with no spares. A set of 667 kVA, 875 amp
regulators follow the transformer. The substation transformer loading is at 96.2%
with 15-year loads.
b. Mechanical Condition of Plant
There are no deficiencies noted for Martis Valley Service Area.
c. System Analysis
Project MV-01 Within the planning period, TDPUD would like to engineer
and then install a new circuit switcher at the Martis Valley
substation.
Estimated Cost: $250,000
i. MV-1 CIRCUIT
Feeder MV-1 serves the area to the southwest of the Martis Valley
Substation. There is approximately 930 kW of load on this feeder. No low
voltage occurs on this feeder with existing or future loads.
ii. MV-2 CIRCUIT
Feeder MV-2 serves the area to the south and southeast of the Martis Valley
Substation. There is approximately 2.4 MW of load on this feeder. No low
voltage occurs on this feeder with existing or future loads.
iii. MV-3 CIRCUIT
Feeder MV-3 serves the area to the west of the Martis Valley Substation.
There is approximately 2.2 MW of load on this feeder. No low voltage
occurs on this feeder with existing or future loads.
iv. MV-4 CIRCUIT
Feeder MV-4 serves the area to the east of the Martis Valley Substation.
2 Load growth was calculated from 01/2014 to present due to skewed results when including earlier historical values.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-12
There is approximately 3.1 MW of load on this feeder. No low voltage
occurs on this feeder with existing or future loads.
d. Contingency
In the event of the loss of a substation transformer, the following devices are
recommended to be switched:
Close switch A19
Close switch A7
Close switch PMS22-2
Close switch A18
Close switch PMS7-2
Minimum Voltages On Martis Valley Service Area During Contingency
Existing 5-year 15-year
A 122.3 122.3 122.3
B 122.5 122.5 122.5
C 122.7 122.7 122.7
Truckee Transformer Loading 89.9% 111.9% 146.1%
Truckee Regulator Loading 99.9% 124.4% 162.4%
Table 6.3-1
*NC=did not converge
There is conductor overloading with 15 year loads and transformer overloading of
111.9% with 5 year loads, which increases to 146.1% with 15 year loads. There is
no low voltage during the planning period.
Project MV-C3 It is recommended to upgrade the existing set of three (3)
single-phase 5 MVA transformers at the Martis Valley
substation to three (3) single-phase 7.5 MVA transformers
in order to maintain capacity at 15-year loading when
transferring load from Truckee to Martis Valley.
Alternatively, portions of Martis Valley could be transferred
to Donner Lake or Truckee substations. The following
additional switching would keep Truckee transformer
loading below 100% at 15-year peak loading when
transferring Truckee to Martis Valley:
Close switch S106
Open switch S136
Estimated Cost: $ 950,000
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-13
Project MV-C6 There is conductor overloading during 5-year and 15-year
loading levels when transferring Donner Lake to Martis
Valley. The conductor is loaded at 104.7% with 15-year
loading levels. It is recommended to rebuild approximately
0.2 miles of 2/0 AWG ACSR with 397 kcmil AAC. This line
begins west of the Deerfield Road and Highway 89
intersection and ends south of the Crossroads Shopping
Center. This project should occur within 5 year loading
levels.
Estimated Cost: $ 57,000
Project MV-C7 It is recommended to rebuild approximately 0.08 miles of
existing 500 kcmil to 750 kcmil between PMS30-1 and the
substation and also between PMS30-2 and the riser. This line
is loaded to 52.8% with existing loading levels and is at
113.6% with 15 year loading levels when Truckee is
transferred to Martis Valley.
Estimated Cost: $ 73,000
MV-1 Feeder
MV-1 has two (2) ties to MV-2, but no ties to adjacent substation feeders. As such,
in order for total substation transfer, MV-1 will have to tie directly to MV-2, which
will then tie to several more feeders.
See the contingency for MV-4 for a full analysis.
MV-2 Feeder
MV-2 has two (2) ties to MV-1 and one additional tie to MV-4. There are no ties
to any adjacent substation feeders from MV-2. In order to serve the load from a
different substation, it will have to be served from MV-4, which will then be served
from a different substation.
See the contingency for MV-4 for a full analysis.
MV-3 Feeder
MV-3 has one (1) tie to Truckee TR-2, two (2) ties to TR-3, one (1) tie to TR-4,
one (1) tie to Donner Lake DL-1 and one additional tie to MV-4.
There is no low voltage or conductor overloading during load transfer with existing
or future loads.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-14
MV-4 Feeder
MV-4 has one (1) tie to Truckee TR-1, one (1) tie to MV-2 and one additional tie
to MV-3.
There is no low voltage or conductor overloading during load transfer with
existing or future loads.
e. Sectionalizing Recommendations
Martis Valley Substation has three (3) 5,000 kVA 120-7.62/13.2 kV distribution
transformers, with SEL-587/551 relays for high side protection. The SEL-587
Instantaneous (IOC) and Time Over-Current (TOC) settings are currently disabled
at the Martis Valley substation. It is recommended to update the Line-to-Line
voltage settings in the SEL-587.
Voltage Highside Protection Transformer Size % Impedance
Martis Valley 115 kV SEL-587/551 (3) 5/6.25 MVA 8.44
The following table shows the fault location impedances for the electronic reclosers
existing on Martis Valley Substation. These impedance values are used on the Form
6’s to locate faults on the line by calculating the approximate distance from the
recloser based on impedance data from the fault. Though these will not give exact
locations of the fault, it will help to narrow down certain areas the fault may have
occurred, making it easier for fault locating.
Substation Recloser R X R0 X0 Miles
Martis
Valley
MV-1 0.86 2.30 1.59 3.03 1.58
MV-2 0.83 2.19 2.13 2.31 2.38
MV-3 1.01 2.72 2.47 4.62 2.72
MV-4 0.79 3.18 1.95 5.56 2.94
The following equipment is recommended for removal or installation on Martis
Valley Substation:
i. MV-1 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 9.45 miles of primary line on this circuit, with both
overhead and underground. There are fuses on this feeder.
There are no recommendations made for this feeder.
ii. MV-2 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 13.23 miles of primary line on this circuit, with a
majority of the line being underground conductor. There is a mixture of
hydraulic reclosers and fuses on this feeder.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-15
The following recommendations are made for this feeder:
a. R35 Fir Drive
It is recommended to replace the existing 4H 70A recloser with a Cooper
Spear recloser with Form 6 control. The interrupt rating on the 4H 70A is
lower than the highest line-to-ground fault current.
Estimated Cost: $ 15,000
iii. MV-3 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 8.81 miles of primary line on this circuit, with a
majority of the line being overhead conductor. There are fuses on this
feeder.
The following recommendations are made for this feeder:
a. R10 Donner Pass Rd
This is a tie recloser between MV-3 and DL-1. The current settings do not
coordinate with DL-1’s feeder reclosers. It is recommended to include
alternate settings in this device in order to coordinate with DL-1. Refer to
the settings sheet at the end of the section.
iv. MV-4 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 8.51 miles of primary line on this circuit, with a
majority of the line being overhead conductor. There is an electronic
recloser and fuses on this feeder.
There are no recommendations made for this feeder.
Martis Valley Substation
Fuse Size
T
Device No. Fuse
Saving
Non Fuse
Saving
MV-1 Recloser 50 12
MV-2 Recloser 50 8
MV-3 Recloser 50 25
MV-4 Recloser 65 30
R25 Joerger Drive Recloser N/A 65
Current in Amperes1001,00010,000100,000Time In Seconds.001
.01
.1
1
10
100
1,000
10,000
100,000
1,000,000
240 A PU U4-US Ext Inv
156 A PU U4-US Ext Inv
179
Minimum Fault
5981
Phase-Ground Fault
TDPUD 2019 Master Plan 10/21/2019
Martis Valley Coordination 7.2 kV
Current in Amperes1001,00010,000100,000Time In Seconds.001
.01
.1
1
10
100
1,000
10,000
100,000
1,000,000
240 A PU U4-US Ext Inv
156 A PU U4-US Ext Inv
179
Minimum Fault
4577
Phase-Phase Fault
TDPUD 2019 Master Plan 10/21/2019
Martis Valley Coordination 7.2 kV
Current in Amperes1001,00010,000100,000Time In Seconds.001
.01
.1
1
10
100
1,000
10,000
100,000
1,000,000
179
Minimum Fault
240 A PU U4-US Ext Inv
156 A PU U4-US Ext Inv
5287
Three Phase Fault
TDPUD 2019 Master Plan 10/21/2019
Martis Valley Coordination 7.2 kV
Current in Amperes101001,00010,000100,000Time In Seconds.01
.1
1
10
100
1,000
10,000
179
Minimum Fault
5981
Phase-Ground Fault
280 A Amp: Curve--133
170 A Amp: Curve--142
240 A PU U4-US Ext Inv
156 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
MV-2 Upline Coordination 7.2 kV
Current in Amperes101001,00010,000100,000Time In Seconds.01
.1
1
10
100
130 A Amp: Curve--117
130 A Amp: Curve--106
280 A Amp: Curve--133
170 A Amp: Curve--142
176
Minimum Fault
3335
R35 Phase-Ground Fault
TDPUD 2019 Master Plan 10/21/2019
MV-2 Coordination 7.2 kV
Current in Amperes1101001,00010,000100,0001,000,000Time In Seconds.01
.1
1
10
100
1,000
10,000
100,000
170 A Amp: Curve--106
380 A Amp: Curve--104
170 A Amp: Curve--140 A+170.00
380 A Amp: Curve--133
5981
Phase-Ground Fault 179
Minimum Fault
240 A PU U4-US Ext Inv
156 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
MV-3 Upline Coordination 7.2 kV
Current in Amperes101001,00010,000100,000Time In Seconds.01
.1
1
10
100
100 -Total Clear
170 A Amp: Curve--106
170 A Amp: Curve--140 A+170.00
380 A Amp: Curve--104
380 A Amp: Curve--133
179
Minimum Fault
5008
100T Phase-Ground Fault
TDPUD 2019 Master Plan 10/21/2019
MV-3 Coordination 7.2 kV
Current in Amperes1101001,00010,000100,0001,000,000Time In Seconds.01
.1
1
10
100
1,000
10,000
100,000
480 A Amp: Curve--133
170 A Amp: Curve--106
480 A Amp: Curve--104
170 A Amp: Curve--140
179
Minimum Fault
5981
Phase-Ground Fault
240 A PU U4-US Ext Inv
156 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
MV-4 Upline Coordination 7.2 kV
Current in Amperes110100
1,00010,000100,000Time In Seconds.01
.1
1
10
100
140 A Amp: Curve--106
140 A Amp: Curve--135
280 A Amp: Curve--101
280 A Amp: Curve--133
170 A Amp: Curve--106
170 A Amp: Curve--140
480 A Amp: Curve--104
480 A Amp: Curve--133
175
Minimum Fault
2591
R25 Phase-Ground Fault
TDPUD 2019 Master Plan 10/21/2019
MV-4 Coordination 7.2 kV
Current in Amperes101001,00010,000100,000Time In Seconds.001
.01
.1
1
10
100
1,000
10,000
100,000
480 A Amp: Curve--101
170 A Amp: Curve--104
480 A Amp: Curve--133
170 A Amp: Curve--140
5981
Phase-Ground Fault 179
Minimum Fault
240 A PU U4-US Ext Inv
156 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
MV-1 Upline Coordination 7.2 kV
Current in Amperes10100 1,00010,000100,000Time In Seconds.01
.1
1
10
100
65 -Total Clear
480 A Amp: Curve--101
170 A Amp: Curve--140
480 A Amp: Curve--133
170 A Amp: Curve--104
176
Minimum Fault
3311
65T Phase-Ground Fault
TDPUD 2019 Master Plan 10/21/2019
7.2 kV
Substation Martis Valley
Feeder MV-1
Location
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 480
Min Trip Ground 170
TCC1P 101
TCC1G 133
TCC2P 104
TCC2G 140
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0.05
TCC1G Mult 1
TCC1G Adder 0.05
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled) Yes
High-Current Trip Ground TCC1 (Enabled) Yes
High-Current Trip Phase TCC2 (enabled) Yes
High-Current Trip Ground TCC2 (Enabled) Yes
High-Current Trip Phase TripX TCC1 8
High-Current Trip Ground TripX TCC1 23
High-Current Trip Phase TripX TCC2 8
High-Current Trip Ground TripX TCC2 23
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)4320
High-Current Lockout Ground (Trip)4080
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Substation
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Martis Valley
Feeder MV-2
Location Substation
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 280
Min Trip Ground 170
TCC1P 101 DISABLE
TCC1G 104 DISABLE
TCC2P 133
TCC2G 142
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0
TCC1G Mult 1
TCC1G Adder 0
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes
High-Current Trip Ground TCC1 (Enabled)Yes
High-Current Trip Phase TCC2 (enabled)Yes
High-Current Trip Ground TCC2 (Enabled)Yes
High-Current Trip Phase TripX TCC1 21
High-Current Trip Ground TripX TCC1 32
High-Current Trip Phase TripX TCC2 21
High-Current Trip Ground TripX TCC2 32
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)6160
High-Current Lockout Ground (Trip)5950
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Martis Valley
Feeder MV-3
Location Substation
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 380
Min Trip Ground 170
TCC1P 104
TCC1G 106
TCC2P 133
TCC2G 140
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0
TCC1G Mult 1
TCC1G Adder 0
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1.5
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes
High-Current Trip Ground TCC1 (Enabled)Yes
High-Current Trip Phase TCC2 (enabled)Yes
High-Current Trip Ground TCC2 (Enabled)Yes
High-Current Trip Phase TripX TCC1 13
High-Current Trip Ground TripX TCC1 30
High-Current Trip Phase TripX TCC2 13
High-Current Trip Ground TripX TCC2 30
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)5320
High-Current Lockout Ground (Trip)5270
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
column, all other settings would remain the same
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
Substation Martis Valley
Feeder MV-3
Location R10 Donner Pass Rd
Device Form 4C
Exis Rec Exis Rec
Min Trip Phase 300 160
Min Trip Ground 100 150 100
TCC1P 101 101
TCC1G 106 106
TCC2P 133 117 133
TCC2G 142 135 142
Oper to LO Phase 3 3
Oper on TCC1 Phase 1 1
Oper to LO Gnd 3 3
Oper on TCC1 Gnd 1 1
TCC1P Mult 0.2 1 0.2
TCC1P Adder 0 0 0
TCC1G Mult 0.2 1 0.2
TCC1G Adder 0 0 0
TCC2P Mult 1 1 1
TCC2P Adder 0 0
TCC2G Mult 0.5 1 0.5
TCC2G Adder 0 0
High-Current Trip Phase (ON/OFF)On Off On
High-Current Trip Ground (ON/OFF)On Off On
High-Current Trip Phase (Trip)6 6
High-Current Trip Ground (Trip)8 8
High-Current Trip Phase (Trip No.)
High-Current Trip Ground (Trip No.)
High-Current Lockout Phase (ON/OFF)On Off Off
High-Current Lockout Ground (ON/OFF)On Off Off
High-Current Lockout Phase (Trip)7 7
High-Current Lockout Ground (Trip)10 10
High-Current Lockout Phase (Trip No.)1 1
High-Current Lockout Ground (Trip No.)1 1
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Martis Valley
Feeder MV-4
Location Substation
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 480
Min Trip Ground 170
TCC1P 104
TCC1G 106
TCC2P 133
TCC2G 140
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0
TCC1G Mult 1
TCC1G Adder 0
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1.5
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes
High-Current Trip Ground TCC1 (Enabled)Yes
High-Current Trip Phase TCC2 (enabled)Yes
High-Current Trip Ground TCC2 (Enabled)Yes
High-Current Trip Phase TripX TCC1 12
High-Current Trip Ground TripX TCC1 32
High-Current Trip Phase TripX TCC2 12
High-Current Trip Ground TripX TCC2 32
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)6240
High-Current Lockout Ground (Trip)6120
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Martis Valley
Feeder MV-4
Location Joerger Dr
Device Form 4C
Exis Rec Exis Rec
Min Trip Phase 280
Min Trip Ground 140
TCC1P 101
TCC1G 102
TCC2P 133
TCC2G 165
Oper to LO Phase 3
Oper on TCC1 Phase 0
Oper to LO Gnd 3
Oper on TCC1 Gnd 0
TCC1P Mult 1
TCC1P Adder 0
TCC1G Mult 1
TCC1G Adder 0
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase (ON/OFF)Off
High-Current Trip Ground (ON/OFF)Off
High-Current Trip Phase (Trip)
High-Current Trip Ground (Trip)
High-Current Trip Phase (Trip No.)
High-Current Trip Ground (Trip No.)
High-Current Lockout Phase (ON/OFF)Off
High-Current Lockout Ground (ON/OFF)Off
High-Current Lockout Phase (Trip)
High-Current Lockout Ground (Trip)
High-Current Lockout Phase (Trip No.)
High-Current Lockout Ground (Trip No.)
column, all other settings would remain the same
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
Substation Martis Valley
Feeder Substation High Side
Location Substation
Device SEL-551
CTR
CTRN
50P1P
51P1P
51P1C
51P1TD
50N1P
51N1P
51N1C
51N1TD
50G1P
51G1P
51G1C
51G1TD
50Q1P
51Q1P
51Q1C
51Q1TD
Rec
OFF
Primary
Exis
15
120
35
6
U4
3
OFF
2
U4
10
OFF
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
OFF
U4
1.5
OFF
OFF
15
U3
Substation Martis Valley
Feeder Substation High Side
Location Substation
Device SEL-587
MVA
VWDG1
VWDG2
CTR1
CTR2
TAP1
TAP2
50P1P
50P1D
50P1H
51P1P
51P1C
51P1TD
50Q1P
50Q1D
51Q1P
51Q1C
51Q1TD
50N1P
50N1D
50N1H
51N1P
51N1C
51N1TD
50P2P
50P2D
50P2H
51P2P
51P2C
51P2TD
50Q2P
50Q2D
51Q2P
51Q2C
51Q2TD
50N2P
50N2D
50N2H
51N2P
51N2C
51N2TD
5
OFF
OFF
U4
12.4
15
OFF
OFF
U4
16000
6.6
OFF
16000
OFF
OFF
U4
15
OFF
2.5
OFF
138
69
OFF
5
OFF
OFF
U4
OFF
U2
OFF
5
U2
3.8
OFF
OFF
OFF
5
240
3.47
3.62
Primary
15
RecExis
Substation
Feeder 2
Location R35
Device Cooper SPEAR
Exis Rec
Min Trip 130
TCC1 106
TCC2 117
TTL 4
Oper #1 TCC1
Oper #2 TCC1
Oper #3 TCC2
Oper #4 TCC2
TCC1 Mult 1
TCC1 Adder 0
TCC1 Min Response Time DISABLE
TCC1 HCT DISABLE
TCC1 HCT Time Delay 0.01
TCC2 Mult 1
TCC2 Adder 0
TCC2 Min Response Time DISABLE
TCC2 HCT DISABLE
TCC2 HCT Time Delay 0.01
Note: Settings in the recommended column that are
the same as the existing settings are not listed unless
otherwise noted.
Martis Valley
Primary
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-16
6.3 TAHOE DONNER SERVICE AREA
The Tahoe Donner Service Area has a projected growth rate of 0.09%3, with losses
compounded annually for the plan period. This service area serves a large area to the north
of Tahoe Donner Substation. A majority of the customers are residential with some
commercial entities, while a majority of the homes served by Tahoe Donner are vacation
homes. There is service to approximately 4,000 customers and a total load of 7.7 MW.
There are existing 3-phase ties between TD-1 and DL-3, TD-2 and DL-2, TR-5 and TD-3
and two separate ties between TR-4 and TD-3.
a. Loading and Capacity
Tahoe Donner Substation has three (3) 5/5.6/6.25/7 MVA 60/12.47 kV
transformers and three distribution bays in service with no spares. The
transformers are followed by a set of 667 kVA, 875 amp regulators.
No equipment exceeds its load rating during the plan period.
b. Mechanical Condition of Plant
There are no deficiencies noted for Tahoe Donner Service Area.
c. System Analysis
i. TD-1 CIRCUIT
Feeder TD-1 serves the area to the west of the Tahoe Donner Substation.
There is approximately 1.2 MW of load on this feeder. No low voltage
occurs on this feeder with existing or future loads.
ii. TD-2 CIRCUIT
Feeder TD-2 serves the area to the north and northwest of the Tahoe Donner
Substation. There is approximately 3.0 MW of load on this feeder.
Project TD-04 It is recommended to rebuild approximately 0.7 miles of
existing 4/0 AWG ACSR to 397 kcmil AAC between
between the intersection of Davos Dr. and Northwoods Blvd
and the intersection of Northwoods Blvd and Northwoods
Blvd. This will improve voltage between the two substations
during load transfer.
Estimated Cost: $ 231,000
3 Load growth was calculated from 01/2014 to present due to skewed results when including 2015 historical values, where TD-1 had been
transferred to Donner Lake.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-17
iii. TD-3 CIRCUIT
Feeder TD-3 serves the area to the west and northeast of the Tahoe Donner
Substation. There is approximately 3.5 MW of load on this feeder. No low
voltage occurs on this feeder with existing or future loads.
d. Phase Balancing Projects
· Move OHP_3814 from B-phase to C-phase
· Move OHP_55201 from B-phase to C-phase
· Move OHP_3923 from A-phase to C-phase
e. Contingency
In the event of the loss of a substation transformer, the following devices are
recommended to be switched:
Close switch A59
Close switch S208
Open fuse F208
Close switch S128
Open fuse F128
Close switch A50
Close fuse F368
Open switch S368
Open switch S-502
Open switch S-514
Open XA21
Open S-516
Minimum Voltages On Tahoe Donner Service Area During Contingency
Existing 5-year 15-year
A 110.8 110.8 110.8
B 112.9 112.9 112.9
C 114.1 114.1 114.1
Donner Lake Transformer Loading 77.2% 77.2% 77.2%
Donner Lake Regulator Loading 65.4% 65.4% 65.4%
Truckee Transformer Loading 67.2% 93.5% 99.6%
Truckee Regulator Loading 74.6% 88.9% 95.9%
Table 6.4-1
*NC=did not converge
Project TD-C2 It is recommended to rebuild approximately 0.83 miles of
existing 4/0 AWG ACSR to 397 kcmil AAC between
between Ramshorn East and the intersection of Davos Dr
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-18
and Northwoods Blvd. This will improve voltage between
the two substations during load transfer.
Estimated Cost: $ 231,000
Project TD-C3 It is recommended to rebuild approximately 0.74 miles of
existing 4/0 AWG ACSR to 397 kcmil AAC between
Ramshorn East and Christie Lane. This will improve voltage
between the two substations during load transfer.
Estimated Cost: $ 206,000
Project TD-C4 It is recommended to rebuild approximately 0.67 miles of
existing 2 AWG ACSR to 397 kcmil AAC between
Muhlebach Way and Chamonix Road. This will improve
voltage between the two substations during load transfer.
Estimated Cost: $ 186,000
Project TD-C5 It is recommended to rebuild approximately 1.0 miles of
existing 2/0 AWG ACSR to 397 kcmil AAC between
Snowpeake Way and Muhlebach Way. This will improve
voltage between the two substations during load transfer.
Estimated Cost: $ 278,200
TD-1 Feeder
TD-1 Feeder can be transferred to Donner Lake DL-3 (switch 166.53649). TD-1
Feeder also has a tie to TD-2.
When transferring load to DL-3 Feeder, there is no transformer overloading,
conductor overloading or low voltage.
TD-2 Feeder
TD-2 Feeder has existing ties to both TD-1 and TD-3, but no available tie points to
different substations.
There is low voltage on TD-2 at all loading levels during contingency.
TD-3 Feeder
TD-3 Feeder has two (2) existing ties to Truckee Substation’s TR-4 Feeder, one
tie to TR-5 and ties to TD-2.
There is no conductor overloading, low voltage or transformer overloading during
the planning period with this switching order.
f. Sectionalizing Recommendations
Tahoe Donner Substation has three (3) 5/7 MVA 60-12.47/7.2 kV distribution
transformers, with SEL-587/551 relays for high side protection.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-19
The following recommendations are made for the Tahoe Donner Substation:
a) Feeder Recloser
New relay settings are shown at the end of this section.
Voltage Highside Protection Transformer Size % Impedance
Tahoe Donner 60 kV SEL-587/551 (3) 5/7 MVA 7.81
The following table shows the fault location impedances for the existing electronic
reclosers on Tahoe Donner Substation. These impedance values are used on the
Form 6’s to locate faults on the line by calculating the approximate distance from
the recloser based on impedance data from the fault. Though these will not give
exact locations of the fault, it will help to narrow down certain areas the fault may
have occurred, making it easier for fault locating.
Substation Recloser R X R0 X0 Miles
Tahoe
Donner
TD-1 1.12 2.29 1.87 3.96 1.60
TD-2 1.26 2.69 2.18 4.93 2.20
TD-3 0.86 2.25 1.63 3.87 1.78
The following equipment is recommended for removal or installation on Tahoe
Donner Substation:
i. TD-1 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 7.28 miles of primary line on this circuit, with a
majority of the line being overhead conductor. There is a mixture of
hydraulic reclosers and fuses on this feeder.
ii. TD-2 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 16.05 miles of primary line on this circuit, with a
majority of the line being overhead conductor. There is a mixture of
hydraulic reclosers and fuses on this feeder.
The following recommendations are made for this feeder:
a. Feeder Recloser
It is recommended to disable the high-current trip settings and increase the
high current lockout setting. Refer to the settings sheet at the end of the
section.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-20
b. Recloser R50 (Wolfgang)
The current settings for this recloser are unknown, therefore it is
recommended replace this recloser with a Spear recloser with Cooper Form
6 control. Refer to the settings sheet at the end of the section.
Estimated Cost: $ 15,000
iii. TD-3 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 21.36 miles of primary line on this circuit, with a
majority of the line being overhead conductor. There is an electronic
recloser and fuses on this feeder.
The following recommendations are made for this feeder:
a. Feeder Recloser
It is recommended to disable the high-current trip settings and increase the
high current lockout setting. Refer to the settings sheet at the end of the
section.
b. Recloser R15 (Sitzmark)
It is recommended to change the phase TCC2 curve from 162 to 117 to better
coordinate with the feeder recloser. Refer to the settings sheet at the end of
the section.
Tahoe Donner Substation
Fuse Size
T
Device No. Fuse
Saving
Non Fuse
Saving
TD-1 Recloser 50 12
TD-2 Recloser 50 12
TD-3 Recloser 50 15
R15 Sitzmark Recloser 30 6
Current in Amperes1001,00010,000100,000Time In Seconds.01
.1
1
10
100
170 A Amp: Curve--104
170 A Amp: Curve--140
480 A Amp: Curve--101
480 A Amp: Curve--133 504 A PU U4-US Ext Inv
960 A PU U4-US Ext Inv
160 A PU U4-US Ext Inv
168 A PU U4-US Ext Inv
180
Minimum Fault
7600
Phase-Ground Fault
TDPUD 2019 Master Plan 10/21/2019
TD-1 Upline Coordination 7.2 kV
Current in Amperes10100
1,00010,000100,000Time In Seconds.01
.1
1
10
480 A Amp: Curve--101
170 A Amp: Curve--104
170 A Amp: Curve--140
480 A Amp: Curve--133
40 -Total Clear
176
Minimum Fault
3519
40T Three Phase Fault
TDPUD 2019 Master Plan 10/21/2019
TD-1 Coordination 7.2 kV
Current in Amperes101001,00010,000100,000Time In Seconds.01
.1
1
10
100
480 A Amp: Curve--101
170 A Amp: Curve--104
170 A Amp: Curve--140
480 A Amp: Curve--133
504 A PU U4-US Ext Inv
960 A PU U4-US Ext Inv
160 A PU U4-US Ext Inv
180
Minimum Fault
7600
Phase-Ground Fault
168 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
TD-2 Upline Coordination 7.2 kV
Current in Amperes1101001,00010,000100,0001,000,000Time In Seconds.01
.1
1
10
100
480 A Amp: Curve--101
170 A Amp: Curve--104
480 A Amp: Curve--133
170 A Amp: Curve--140
65 -Total Clear
5775
65T Phase-Ground Fault
172
Minimum Fault
TDPUD 2019 Master Plan 10/21/2019
TD-2 Coordination 7.2 kV
Current in Amperes101001,00010,000100,000Time In Seconds.01
.1
1
10
100
280 A Amp: Curve--104
280 A Amp: Curve--133
170 A Amp: Curve--140
170 A Amp: Curve--106
7600
Phase-Ground Fault 180
Minimum Fault
504 A PU U4-US Ext Inv
168 A PU U4-US Ext Inv
960 A PU U4-US Ext Inv
160 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
TD-3 Upline Coordination 7.2 kV
Current in Amperes101001,00010,000Time In Seconds.01
.1
1
10
100
200 A Amp: Curve--101
100 A Amp: Curve--106
100 A Amp: Curve--142
200 A Amp: Curve--117
280 A Amp: Curve--133
280 A Amp: Curve--104
170 A Amp: Curve--106
170 A Amp: Curve--140
2435
R15 Three Phase Fault
172
Minimum Fault
TDPUD 2019 Master Plan 10/21/2019
TD-3 Coordination 7.2 kV
Current in Amperes1001,00010,000100,000Time In Seconds.1
1
10
100
1,000
504 A PU U4-US Ext Inv
168 A PU U4-US Ext Inv
160 A PU U4-US Ext Inv
960 A PU U4-US Ext Inv
7128
Three Phase Fault
180
Minimum Fault
TDPUD 2019 Master Plan 10/21/2019
Tahoe Donner Coordination 7.2 kV
Current in Amperes1001,00010,000100,000Time In Seconds.1
1
10
100
1,000
504 A PU U4-US Ext Inv
168 A PU U4-US Ext Inv
180
Minimum Fault
7600
Phase-Ground Fault
160 A PU U4-US Ext Inv
960 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
Tahoe Donner Coordination 7.2 kV
Current in Amperes1001,00010,000100,000Time In Seconds.1
1
10
100
1,000
504 A PU U4-US Ext Inv
168 A PU U4-US Ext Inv
6172
Phase-Phase Fault
180
Minimum Fault
160 A PU U4-US Ext Inv
960 A PU U4-US Ext Inv
TDPUD 2019 Master Plan 10/21/2019
Tahoe Donner Coordination 7.2 kV
Substation Tahoe Donner
Feeder TD-1
Location
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 480
Min Trip Ground 170
TCC1P 101
TCC1G 104
TCC2P 133
TCC2G 140
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0.05
TCC1G Mult 1
TCC1G Adder 0.05
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes OFF
High-Current Trip Ground TCC1 (Enabled)Yes OFF
High-Current Trip Phase TCC2 (enabled)Yes OFF
High-Current Trip Ground TCC2 (Enabled)Yes OFF
High-Current Trip Phase TripX TCC1 11
High-Current Trip Ground TripX TCC1 32
High-Current Trip Phase TripX TCC2 11
High-Current Trip Ground TripX TCC2 32
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)5760 6500
High-Current Lockout Ground (Trip)5610 6500
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Substation
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Tahoe Donner
Feeder TD-2
Location
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 480
Min Trip Ground 170
TCC1P 101
TCC1G 104
TCC2P 133
TCC2G 170
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0.05
TCC1G Mult 1
TCC1G Adder 0.05
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes OFF
High-Current Trip Ground TCC1 (Enabled)Yes OFF
High-Current Trip Phase TCC2 (enabled)Yes OFF
High-Current Trip Ground TCC2 (Enabled)Yes OFF
High-Current Trip Phase TripX TCC1 11
High-Current Trip Ground TripX TCC1 32
High-Current Trip Phase TripX TCC2 11
High-Current Trip Ground TripX TCC2 32
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)5760 6500
High-Current Lockout Ground (Trip)5610 6500
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Note: Only the recommended changes are noted in the Rec
Substation
Primary Alternate 1
column, all other settings would remain the same
Substation Tahoe Donner
Feeder TD-3
Location
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 280
Min Trip Ground 170
TCC1P 101 104
TCC1G 106
TCC2P 133
TCC2G 140
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0
TCC1G Mult 1
TCC1G Adder 0.05 0
TCC2P Mult 1
TCC2P Adder 0.05 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes OFF
High-Current Trip Ground TCC1 (Enabled)Yes OFF
High-Current Trip Phase TCC2 (enabled)Yes OFF
High-Current Trip Ground TCC2 (Enabled)Yes OFF
High-Current Trip Phase TripX TCC1 18.9
High-Current Trip Ground TripX TCC1 32
High-Current Trip Phase TripX TCC2 18.9
High-Current Trip Ground TripX TCC2 32
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)5760 6500
High-Current Lockout Ground (Trip)5610 6500
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation
Primary Alternate 1
Substation Tahoe Donner
Feeder TD-3
Location
Device Form 4
Exis Rec Exis Rec
Min Trip Phase 200
Min Trip Ground 100
TCC1P 101
TCC1G 106
TCC2P 162 117
TCC2G 142
Oper to LO Phase 2
Oper on TCC1 Phase 1
Oper to LO Gnd 2
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0
TCC1G Mult 1
TCC1G Adder 0
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes
High-Current Trip Ground TCC1 (Enabled)Yes
High-Current Trip Phase TCC2 (enabled)Yes
High-Current Trip Ground TCC2 (Enabled)Yes
High-Current Trip Phase TripX TCC1 6
High-Current Trip Ground TripX TCC1 9
High-Current Trip Phase TripX TCC2 6
High-Current Trip Ground TripX TCC2 9
High-Current Trip Phase Time Delay TCC1 0.05
High-Current Trip Ground Time Delay TCC1 0.05
High-Current Trip Phase Time Delay TCC1 0.05
High-Current Trip Ground Time Delay TCC1 0.05
High-Current Lockout Phase (Enabled)No
High-Current Lockout Ground (Enabled)No
High-Current Lockout Phase (Trip)
High-Current Lockout Ground (Trip)
High-Current Lockout Phase (Trip No.)
High-Current Lockout Ground (Trip No.)
Note: Only the recommended changes are noted in the Rec
R15 Sitzmark
Primary Alternate 1
column, all other settings would remain the same
Substation Tahoe Donner
Feeder Substation High Side
Location Substation
Device SEL-551
CTR
CTRN
50P1P
51P1P
51P1C
51P1TD
50N1P
51N1P
51N1C
51N1TD
50G1P
51G1P
51G1C
51G1TD
50Q1P
51Q1P
51Q1C
51Q1TD
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
U3
15
1.5
OFF
OFF
OFF
OFF
U4
8
U4
2.5
U4
1.25
OFF
120
73 OFF
4
Primary
Exis Rec
40
Substation Tahoe Donner
Feeder Substation High Side
Location Substation
Device SEL-587
MVA
VWDG1
VWDG2
CTR1
CTR2
TAP1
TAP2
50P1P
50P1D
50P1H
51P1P
51P1C
51P1TD
50Q1P
50Q1D
51Q1P
51Q1C
51Q1TD
50N1P
50N1D
50N1H
51N1P
51N1C
51N1TD
50P2P
50P2D
50P2H
51P2P
51P2C
51P2TD
50Q2P
50Q2D
51Q2P
51Q2C
51Q2TD
50N2P
50N2D
50N2H
51N2P
51N2C
51N2TD
U4
12.4
5
OFF
OFF
U4
15
OFF
OFF
16000
OFF
OFF
U2
2.5
OFF
5
OFF
OFF
U4
15
OFF
16000
OFF
OFF
U4
6.6
1.25 3
OFF
5
73 OFF
4 4.2
U4
8.1
OFF 73
5
40
120
2.78
OFF
138
69
Primary
Exis Rec
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-21
6.4 TRUCKEE SERVICE AREA
The Truckee Service Area has a projected growth rate of 0.05% with losses compounded
annually for the plan period. This service area serves the central portion of TDPUD’s
system. This substation serves approximately 3,100 customers and a total load of 10.5 MW.
There are existing 3-phase ties between TR-1 and MV-4, TR-5 and TD-3, two ties between
TR-2 and MV-3, two ties between TR-3 and MV-3, one tie between TR-4 and MV-3 and
TR-4 and DL-1.
a. Loading and Capacity
Truckee Substation has three (3) single-phase 5/5.6/6.25/7 MVA 69/12.47 kV
transformers and six (6) distribution bays with no spares. There are a set of 667
kVA, 875 amp regulators after the transformers. The substation transformer loading
is at 124.7% with 15-year loads.
b. Mechanical Condition of Plant
There are no deficiencies noted for Truckee Service Area.
c. System Analysis
Project TR-03 This project improves the Truckee Substation control house
and spill containment.
Estimated Cost: $970,000
i. TR-1 CIRCUIT
Feeder TR-1 serves the area to the east of the Truckee Substation. There is
approximately 1.1 MW of load on this feeder. No low voltage occurs on this
feeder with existing or future loads.
Project TR-01 This portion of the line has over 31 amps on a single phase.
It is recommended to rebuild approximately 0.22 miles of
single-phase 2 AWG ACSR with three-phase 2 AWG ACSR
from the intersection of Glenshire Dr. and Olympic Blvd to
the intersection of Olympic Blvd and East Ridge Rd.
Estimated Cost: $ 56,100
ii. TR-2 CIRCUIT
Feeder TR-2 serves a small area to the south of Truckee Substation. There
is approximately 0.8 MW of load on this feeder. No low voltage occurs on
this feeder with existing or future loads.
iii. TR-3 CIRCUIT
Feeder TR-3 serves an area to the southwest of Truckee Substation. There
is a maximum peak of approximately 735 kW of load on this feeder. No low
voltage occurs on this feeder with existing or future loads.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-22
iv. TR-4 CIRCUIT
Feeder TR-4 serves an area to the west of Truckee Substation. There is a
maximum peak of approximately 4.4 MW of load on this feeder. No low
voltage occurs on this feeder with existing or future loads.
v. TR-5 CIRCUIT
Feeder TR-5 serves an area to the north and northeast of Truckee Substation.
There is a maximum peak of approximately 2.3 MW of load on this feeder.
No low voltage occurs on this feeder with existing or future loads.
Project TR-02 This portion of the line has over 58 amps on a single phase.
It is recommended to rebuild approximately 1.22 miles of
single-phase 2 AWG ACSR with three-phase 2 AWG ACSR
from the intersection of Rainbow Dr. and Highway 89 north
to the intersection of East Alder Creek Rd. and Pine Forest
Rd..
Estimated Cost: $ 467,000
vi. TR-6 CIRCUIT
Feeder TR-6 serves an area to the northeast of Truckee Substation. There is
a maximum peak of approximately 1.1 MW of load on this feeder. No low
voltage occurs on this feeder with existing or future loads.
d. Phase Balancing Projects
· Move OHP_91071 from A-phase to C-phase
· Move XFMR-01049634 from A-phase to C-phase
e. Contingency
In the event of the loss of a substation transformer, the following devices are
recommended to be switched:
Close switch S-128
Open fuse F-208
Close switch A-28
Open switch A-49
Close switch S-368
Open fuse F-368
Close switch A-50
Close switch A-16
Close switch PMS3-2
Open switch A18
Close switch PMS27-1
Close switch A-19
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-23
Minimum Voltages On Truckee Service Area During Contingency
Existing 5-year 15-year
A 117.9 117.9 117.9
B 116.5 116.5 116.5
C 118.9 118.9 118.9
Martis Valley Transformer Loading 64.3% 85.8% 118.9%
Martis Valley Regulator Loading 63.8% 85.1% 118.0%
Tahoe Donner Transformer Loading 69.3% 71.4% 74.6%
Tahoe Donner Regulator Loading 76.9% 79.3% 82.9%
Table 6.5-1
Project TR-C1 It is recommended to rebuild approximately 0.33 miles of 2
AWG ACSR with 4/0 AWG ACSR. This line is located
between Spring Lane and Levone Ave to around Tahoe Dr
and Donner Way.
Estimated Cost: $ 94,000
Project TR-C2 It is recommended to rebuild approximately 0.59 miles of
4/0 AWG ACSR with 397 kcmil AAC. This line is located
on W River St. between Bridge St. and McIver
Crossing/Foxmead Lane. This project should occur within 5
year loading levels.
Estimated Cost:$168,000
Project TR-C3 It is recommended to rebuild approximately 0.15 miles of
500 kcmil with 750 kcmil. This line is located
perpendicular to California 267, near Ranch Way.
Estimated Cost: $ 137,000
Project TR-C4 It is recommended to upgrade the existing set of three (3)
single-phase 5 MVA transformers at the Truckee substation
to three (3) single-phase 7.5 MVA transformers in order to
maintain capacity at 15-year loading when transferring load
from Martis Valley or Tahoe Donner to Truckee. At existing
loading, the transformers are at 146% capacity when Martis
Valley is transferred.
Alternatively, portions of Truckee could be transferred to
Donner Lake and Tahoe Donner when picking up Martis
Valley. The following additional switching would keep
Truckee transformer loading below 100% at 15-year peak
loading when transferring Martis Valley to Truckee:
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-24
Close switch S106
Open switch S136
Close switch PMS26-1
Open switch A55
Estimated Cost: $ 750,000
Project TR-C5 There is conductor overloading during 5-year and 15-year
loading levels when transferring Martis Valley to Truckee.
The conductor is loaded at 81% with existing loading levels
and 137.2% at 15-year loading levels. It is recommended to
rebuild approximately 1.01 miles of 4/0 AWG ACSR with
397 kcmil AAC. This line begins east of the W River St. and
Bridge St. intersection and ends near the Truckee substation.
This project should occur within 5 year loading levels.
Estimated Cost: $ 51,000
TR-1 Feeder
TR-1 Feeder can be transferred to Martis Valley MV-4 (switch 166.1669), as well
as ties to TR-2 and TR-6. When transferring load to MV-4 Feeder, there is no
transformer overloading, conductor overloading or low voltage.
TR-2 Feeder
TR-2 Feeder has two (2) ties to Martis Valley MV-3 Feeder, as well as ties to TR-
1 and TR-3. When transferring load to MV-4 Feeder, there is no transformer
overloading, conductor overloading or low voltage. Switch 166.1679 should be
closed to transfer load.
TR-3 Feeder
TR-3 Feeder has two (2) ties to Martis Valley MV-3 Feeder, as well as ties to TR-
1 and TR-3. When transferring load to MV-3 Feeder, there is no transformer
overloading, conductor overloading or low voltage. Switch 166.12658 should be
closed to transfer load.
TR-4 Feeder
TR-4 Feeder has two (2) ties to Tahoe Donner TD-3 Feeder, one (1) tie to Martis
Valley MV-3 Feeder, as well as ties to TR-3 and TR-5.
When transferring load to TD-3 and MV-3, there is no transformer overloading,
conductor overloading or low voltage during the planning period.
TR-5 Feeder
TR-5 Feeder has one (1) tie to Tahoe Donner TD-3 Feeder, as well as ties to TR-4
and TR-6. When transferring load to MV-3 Feeder, there is no transformer
overloading, conductor overloading or low voltage. Fuse 168.6010 should be closed
to transfer load.
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-25
TR-6 Feeder
TR-6 Feeder has ties to TR-1 and TR-5 but no additional ties to other substations.
When transferring load to TR-5 Feeder, there is no transformer overloading,
conductor overloading or low voltage. Switch 166.10096 should be closed to
transfer load.
f. Sectionalizing Recommendations
Truckee Substation has three (3) 5/7 kVA 60-12.47/7.2 kV distribution
transformers, with high-side protection from the utility. The SEL-587
Instantaneous (IOC) and Time Over-Current (TOC) settings are currently disabled
at the Truckee substation.
The following recommendations are made for the Truckee Substation:
a) Feeder Recloser
New relay settings are shown at the end of this section.
Voltage Highside Protection Transformer Size % Impedance
Truckee 60 kV S&C SMD-1A Slow 150A (3) 5/7 MVA
7.97 (Average
of the three
operating
transformers)
The following table shows the fault location impedances for the electronic reclosers
on Truckee Substation. These impedance values are used on the Form 6’s to locate
faults on the line by calculating the approximate distance from the recloser based
on impedance data from the fault. Though these will not give exact locations of the
fault, it will help to narrow down certain areas the fault may have occurred, making
it easier for fault locating.
Substation Recloser R X R0 X0 Miles
Truckee
TR-1 0.81 2.83 2.15 5.42 3.06
TR-2 0.13 1.12 0.28 1.12 0.32
TR-3 1.06 1.85 2.54 2.30 2.43
TR-4 1.10 2.44 2.57 4.44 2.69
TR-5 1.08 2.37 2.52 3.83 2.70
TR-6 0.77 2.65 2.19 4.82 3.06
i. TR-1 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 16.96 miles of primary line on this circuit, with a
majority of the line being underground conductor.
There are recommendations made for this feeder. Refer to the settings sheets
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-26
at the end of this section
ii. TR-2 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 1.12 miles of primary line on this circuit, with a
majority of the line being overhead conductor.
There are recommendations made for this feeder. Refer to the settings sheets
at the end of this section
iii. TR-3 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 4.68 miles of primary line on this circuit, with a
majority of the line being underground conductor.
There are recommendations made for this feeder. Refer to the settings sheets
at the end of this section
iv. TR-4 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 11.43 miles of primary line on this circuit, with
both underground and overhead conductor. There is a mixture of hydraulic
reclosers and fuses on this feeder.
There are recommendations made for this feeder. Refer to the settings sheets
at the end of this section
v. TR-5 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 41.41 miles of primary line on this circuit, with a
majority of the line being underground conductor. There is a mixture of
electronic reclosers and fuses on this feeder. The district has recently
installed two SPEAR reclosing units on this feeder.
There are recommendations made for this feeder. Refer to the settings sheets
at the end of this section
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-27
vi. TR-6 Feeder
This feeder is protected by a NOVA recloser with Cooper Form 6 control.
There are approximately 10.58 miles of primary line on this circuit, with a
majority of the line being underground conductor. There is a mixture of
electronic reclosers and fuses on this feeder.
There are recommendations made for this feeder. Refer to the settings sheets
at the end of this section
Truckee Substation
Fuse Size
T
Device No. Fuse
Saving
Non Fuse
Saving
TR-1 Recloser 65 15
TR-2 Recloser 65 15
TR-3 Recloser 65 15
TR-4 Recloser 65 15
TR-5 Recloser 65 12
TR-6 Recloser N/A 20
R70 Alder Recloser 40 15
R40 Hwy 89 Recloser 20 3
R45 RainBow Recloser 25 6
R80 Recloser 30 8
Current in Amperes100 1,00010,000Time In Seconds.01
.1
1
10
100
140 A Amp: Curve--106
280 A Amp: Curve--104
140 A Amp: Curve--165
280 A Amp: Curve--133
3099
Phase-Ground Fault
176
Minimum Fault
65 -Total Clear
TDPUD 2019 Master Plan 10/21/2019
TR-1 Coordination 7.2 kV
Current in Amperes10100 1,00010,000Time In Seconds.01
.1
1
10
100
25 -Total Clear
474
Minimum Fault
6727
25T Phase-Ground Fault
280 A Amp: Curve--104
170 A Amp: Curve--165
280 A Amp: Curve--133
170 A Amp: Curve--106
TDPUD 2019 Master Plan 10/21/2019
TR-2 Coordination 7.2 kV
Current in Amperes10100 1,00010,000Time In Seconds.01
.1
1
10
100
65 -Total Clear
7064
65T Phase-Ground Fault
179
Minimum Fault
170 A Amp: Curve--106
170 A Amp: Curve--165
280 A Amp: Curve--104
280 A Amp: Curve--133
TDPUD 2019 Master Plan 10/21/2019
TR-3 Coordination 7.2 kV
Current in Amperes1001,00010,000Time In Seconds.01
.1
1
10
100
65 -Total Clear
465
Minimum Fault
140 A Amp: Curve--106
140 A Amp: Curve--165
280 A Amp: Curve--104
280 A Amp: Curve--133
4671
65T Three Phase Fault
TDPUD 2019 Master Plan 10/21/2019
TR-4 Coordination 7.2 kV
Current in Amperes10100
1,00010,000Time In Seconds.001
.01
.1
1
10
100
3507
R70 Three Phase Fault 172
Minimum Fault 2189
R40 Phase-Ground Fault
2074
R45 Phase-Ground Fault
100 A Amp: Curve--101
100 A Amp: Curve--161
100 A Amp: Curve--132
100 A Amp: Curve--101
140 A Amp: Curve--106
200 A Amp: Curve--117
140 A Amp: Curve--119
200 A Amp: Curve--104
170 A Amp: Curve--151
480 A Amp: Curve--117
TDPUD 2019 Master Plan 10/21/2019
TR-5 Coordination 7.2 kV
Current in Amperes101001,00010,000100,000Time In Seconds.1
1
10
100
250 A Amp: Curve--101
250 A Amp: Curve--117
140 A Amp: Curve--135
140 A Amp: Curve--104
170 A Amp: Curve--151
480 A Amp: Curve--117
480 A Amp: Curve--101
170 A Amp: Curve--106
5277
R80 Three Phase Fault
178
Minimum Fault
TDPUD 2019 Master Plan 10/21/2019
TR-6 Coordination 7.2 kV
Substation Truckee
Feeder TR-1
Location Substation
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 280
Min Trip Ground 140
TCC1P 104
TCC1G 106
TCC2P 133
TCC2G 165
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0
TCC1G Mult 1
TCC1G Adder 0
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes OFF
High-Current Trip Ground TCC1 (Enabled)Yes OFF
High-Current Trip Phase TCC2 (enabled)Yes OFF
High-Current Trip Ground TCC2 (Enabled)Yes OFF
High-Current Trip Phase TripX TCC1 8
High-Current Trip Ground TripX TCC1 15
High-Current Trip Phase TripX TCC2 8
High-Current Trip Ground TripX TCC2 15
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)5500 6700
High-Current Lockout Ground (Trip)6000 6700
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Truckee
Feeder TR-2
Location Substation
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 280
Min Trip Ground 170
TCC1P 104
TCC1G 106
TCC2P 133
TCC2G 165
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1.25
TCC1P Adder 0
TCC1G Mult 1.25
TCC1G Adder 0
TCC2P Mult 2
TCC2P Adder 0
TCC2G Mult 2
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes OFF
High-Current Trip Ground TCC1 (Enabled)Yes OFF
High-Current Trip Phase TCC2 (enabled)Yes OFF
High-Current Trip Ground TCC2 (Enabled)Yes OFF
High-Current Trip Phase TripX TCC1 13
High-Current Trip Ground TripX TCC1 20
High-Current Trip Phase TripX TCC2 14
High-Current Trip Ground TripX TCC2 22
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)5500 6700
High-Current Lockout Ground (Trip)6000 6700
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Primary Alternate 1
Substation Truckee
Feeder TR-3
Location Substation
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 280
Min Trip Ground 170
TCC1P 104
TCC1G 106
TCC2P 133
TCC2G 165
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1.25
TCC1P Adder 0
TCC1G Mult 1.25
TCC1G Adder 0
TCC2P Mult 2
TCC2P Adder 0
TCC2G Mult 2
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes OFF
High-Current Trip Ground TCC1 (Enabled)Yes OFF
High-Current Trip Phase TCC2 (enabled)Yes OFF
High-Current Trip Ground TCC2 (Enabled)Yes OFF
High-Current Trip Phase TripX TCC1 20
High-Current Trip Ground TripX TCC1 31
High-Current Trip Phase TripX TCC2 20
High-Current Trip Ground TripX TCC2 32
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)5500 6700
High-Current Lockout Ground (Trip)6000 6700
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Truckee
Feeder TR-4
Location Substation
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 280
Min Trip Ground 140
TCC1P 104
TCC1G 106
TCC2P 133
TCC2G 165
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0
TCC1G Mult 1
TCC1G Adder 0
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled) Yes OFF
High-Current Trip Ground TCC1 (Enabled) Yes OFF
High-Current Trip Phase TCC2 (enabled) Yes OFF
High-Current Trip Ground TCC2 (Enabled) Yes OFF
High-Current Trip Phase TripX TCC1 8
High-Current Trip Ground TripX TCC1 15
High-Current Trip Phase TripX TCC2 8
High-Current Trip Ground TripX TCC2 15
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)5500 6700
High-Current Lockout Ground (Trip)6000 6700
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Primary
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Alternate 1
Substation Truckee
Feeder TR-5
Location Substation
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 480
Min Trip Ground 170
TCC1P 101 OFF
TCC1G 106 OFF
TCC2P 117
TCC2G 151
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0.08
TCC1G Mult 1
TCC1G Adder 0.08
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes OFF
High-Current Trip Ground TCC1 (Enabled)Yes OFF
High-Current Trip Phase TCC2 (enabled)Yes OFF
High-Current Trip Ground TCC2 (Enabled)Yes OFF
High-Current Trip Phase TripX TCC1 11
High-Current Trip Ground TripX TCC1 31
High-Current Trip Phase TripX TCC2 11
High-Current Trip Ground TripX TCC2 31
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)5700 6700
High-Current Lockout Ground (Trip)5600 6700
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Primary Alternate 1
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Substation Truckee
Feeder TR-5
Location Alder R70
Device Form 6 TS
Exis Rec Exis Rec
Min Trip Phase 200
Min Trip Ground 140
TCC1P 102 104
TCC1G 113 106
TCC2P 116 117
TCC2G 135 119
Oper to LO Phase 4
Oper on TCC1 Phase 2
Oper to LO Gnd 4
Oper on TCC1 Gnd 2
TCC1P Mult 0.5 1
TCC1P Adder 0 0
TCC1G Mult 0.15 1
TCC1G Adder 0.2 0
TCC2P Mult 7 1
TCC2P Adder 0 0
TCC2G Mult 1.1 1
TCC2G Adder 0 0
High-Current Trip Phase TCC1 (enabled)Yes No
High-Current Trip Ground TCC1 (Enabled)No
High-Current Trip Phase TCC2 (enabled)No
High-Current Trip Ground TCC2 (Enabled)No
High-Current Trip Phase TripX TCC1 5
High-Current Trip Ground TripX TCC1 0
High-Current Trip Phase TripX TCC2 0
High-Current Trip Ground TripX TCC2 0
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0
High-Current Trip Phase Time Delay TCC1 0
High-Current Trip Ground Time Delay TCC1 0
High-Current Lockout Phase (Enabled)No
High-Current Lockout Ground (Enabled)No
High-Current Lockout Phase (Trip)0
High-Current Lockout Ground (Trip)0
High-Current Lockout Phase (Trip No.)0
High-Current Lockout Ground (Trip No.)0
Note: Only the recommended changes are noted in the Rec
column, all other settings would remain the same
Alternate 1Primary
Substation Truckee
Feeder TR-6
Location Substation
Device Form 6
Exis Rec Exis Rec
Min Trip Phase 480
Min Trip Ground 170
TCC1P 101
TCC1G 106
TCC2P 117
TCC2G 151
Oper to LO Phase 3
Oper on TCC1 Phase 1
Oper to LO Gnd 3
Oper on TCC1 Gnd 1
TCC1P Mult 1
TCC1P Adder 0.08
TCC1G Mult 1
TCC1G Adder 0.08
TCC2P Mult 1
TCC2P Adder 0
TCC2G Mult 1
TCC2G Adder 0
High-Current Trip Phase TCC1 (enabled)Yes OFF
High-Current Trip Ground TCC1 (Enabled)Yes OFF
High-Current Trip Phase TCC2 (enabled)Yes OFF
High-Current Trip Ground TCC2 (Enabled)Yes OFF
High-Current Trip Phase TripX TCC1 11
High-Current Trip Ground TripX TCC1 31
High-Current Trip Phase TripX TCC2 11
High-Current Trip Ground TripX TCC2 31
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Trip Phase Time Delay TCC1 0.016
High-Current Trip Ground Time Delay TCC1 0.016
High-Current Lockout Phase (Enabled)Yes
High-Current Lockout Ground (Enabled)Yes
High-Current Lockout Phase (Trip)5500 6700
High-Current Lockout Ground (Trip)6000 6700
High-Current Lockout Phase (Trip No.)1
High-Current Lockout Ground (Trip No.)1
Primary Alternate 1
column, all other settings would remain the same
Note: Only the recommended changes are noted in the Rec
Substation
Feeder 5
Location R40
Device Cooper SPEAR
Exis Rec
Min Trip 140 100
TCC1 101
TCC2 161
TTL 4
Oper #1 TCC1
Oper #2 TCC1
Oper #3 TCC2
Oper #4 TCC2
TCC1 Mult 1
TCC1 Adder 0
TCC1 Min Response Time DISABLE
TCC1 HCT DISABLE
TCC1 HCT Time Delay DISABLE
TCC2 Mult 1
TCC2 Adder 0
TCC2 Min Response Time DISABLE
TCC2 HCT DISABLE
TCC2 HCT Time Delay DISABLE
Note: Settings in the recommended column that are
the same as the existing settings are not listed unless
otherwise noted.
Truckee
Primary
Substation
Feeder 5
Location R45
Device Cooper SPEAR
Exis Rec
Min Trip 125 100
TCC1 101
TCC2 132
TTL 4
Oper #1 TCC1
Oper #2 TCC1
Oper #3 TCC2
Oper #4 TCC2
TCC1 Mult 1
TCC1 Adder 0
TCC1 Min Response Time DISABLE
TCC1 HCT DISABLE
TCC1 HCT Time Delay DISABLE
TCC2 Mult 1
TCC2 Adder 0
TCC2 Min Response Time DISABLE
TCC2 HCT DISABLE
TCC2 HCT Time Delay DISABLE
Note: Settings in the recommended column that are
the same as the existing settings are not listed unless
otherwise noted.
Truckee
Primary
Substation
Feeder 6
Location R80
Device Cooper Form 4
Primary
Exis Rec
Min Trip Phase 250 150
Min Trip Ground 140 80
TCC1P 101
TCC1G 104
TCC2P 117
TCC2G 135
Oper to LO Phase 4
Oper on TCC1 Phase 2
Oper to LO Gnd 4
Oper on TCC1 Gnd 2
TCC1P Mult
TCC1P Adder 0.02
TCC1G Mult
TCC1G Adder 0.02
TCC2P Mult
TCC2P Adder
TCC2G Mult
TCC2G Adder
Note: Settings in the recommended column that are
the same as the existing settings are not listed unless
otherwise noted.
Truckee
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-28
6.6 SYSTEM WIDE IMPROVEMENTS
In addition to the recommendations provided for the individual substations in the District’s
service territory, there are several other system-wide improvements that are recommended
through the 15 year planning period.
a. Pole Replacements
The District makes provisions every year to replace aging or physically deteriorated
poles on their system. It is therefore recommended to replace approximately 250
poles within the next 5 years.
Estimated Cost: $ 1,500,000
b. Solar Awning Project
The District is interested in installing a photovoltaic system on the District
headquarters building by 2020. Not only would the District be reducing its own
carbon footprint, all District’s customers would benefit with a lower District
complex electric bill. Additionally, all generation would count towards the district’s
renewable portfolio requirements.
Estimated Cost: $ 150,000
c. Optical Communication Line Installation
The District has 25 electric and 55 water facilities located throughout the service
territory. These facilities include electric substations, protection devices, planned
AMI data concentrators, pump stations, wells, storage tanks, and control valves.
Communication media includes leased data circuits, dial-up telephone lines,
cellular modems, and radio systems. These communication systems, which are
integral to District SCADA systems, are antiquated, difficult to maintain, unreliable
and have limited bandwidth. The District has been installing optical communication
lines since 2011 to replace these media systems. Optical communication lines and
associated equipment provide a robust infrastructure that improves data capacity
and communications reliability to District facilities. Transitioning to optical cable
technology allows the District to "future proof" communications infrastructure and
is the best option for communication cable media.
The District has completed 4 phases of optical communication line installation.
Four additional phases are expected to be required for connection to all remaining
District facilities. Upon completion, there will be a redundant network to all
facilities, with 2 distinct physical paths from each facility back to the main office.
This means that a single contingency outage will cause no interruption of
communication within the network. Electric and water facilities benefit equally
from the completed system, therefore the costs associated with procurement and
installation will be evenly split between the electric and water departments.
Estimated Cost: $ 4,234,000
Truckee Donner Public Utility District
2019 Electric System Master Plan Section 6.0
6-29
d. Fuse Replacement Project
The District is interested in replacing all expulsion fuses with ELF current limiting
fuses. The District will start at the Tahoe Donner neighborhood and expects to
replace all fuses by the end of 2021. From 2022-2025, the District will replace all
expulsion fuses in the Prosser and Sierra Meadows areas. Table 6-6-1 and Table 6-
6-2 describes the conversion and transformer tables for ELF current limiting fuses
Estimated Cost: $ 1,775,000
T-LINK ELF 6A ELF 8A ELF
12A
ELF
20A
ELF
30A
ELF
50A
ELF
80A
3T X
6T X
8T X
10T X
15T X
20T X
25T X
40T X
65T X
Conversion Table
Table 6-6-1
XFMR ELF
6A ELF 8A ELF
12A
ELF
20A
ELF
30A
ELF
50A
ELF
80A
5 KVA X
10 KVA X
15 KVA X
25 KVA X
37.5 KVA X
50 KVA X
75 KVA X
100 KVA X
Transformer Table
Table 6-6-2