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HomeMy WebLinkAbout16 Contract for Failed Transformer at Truckee SubAgenda Item # 16 ACTION To: Board of Directors From: Joe Horvath Date: July 15, 2015 Subject: Consideration of a Contract For Repair of a Failed Transformer at Truckee Substation and Dispensing with Competitive Bidding 1. WHY THIS MATTER IS BEFORE THE BOARD Only the Board can dispense with the competitive bidding process necessary to rebuild or replace the failed substation transformer. 2. HISTORY On the morning of Friday, February 6, 2015 a severe windstorm hit the greater Truckee Tahoe area. Numerous trees fell into power lines across the District causing multiple power outages. District crews worked through Sunday, February 8 to restore service to all customers. At about 9:30AM on Friday morning, a tree fell into the overhead lines near the District's Truckee Substation. The resulting fault current brought about the operation of several protective devices including 12kV circuit reclosers and the 60kV circuit breaker, which tripped the entire substation off-line. Two of the reclosers involved with this incident failed catastrophically. These failures were later found to be due to manufacturing defects. In addition, one of the substation transformers (phase A unit) experienced a "sudden pressure" event and had tripped the corresponding sudden pressure relay. A sudden pressure event is indicative of an internal fault inside the transformer. As a precautionary measure, the District hired a testing firm to take oil samples from all the substation transformers and to perform addition electrical testing on the phase A transformer. Oil samples from the phase A transformer displayed the presence of acetylene gas, an indicator of some level of internal arcing due to a short circuit condition within the transformer. Subsequent internal inspection discovered that pieces of winding insulation had broken off the core and settled to the bottom of the tank. This was a clear indication of a transformer winding failure. This unit cannot be re -energized and requires refurbishment or replacement. 3. NEW INFORMATION The Truckee Substation transformers were all manufactured by the R.E. Uptegraff company of Scottdale, Pennsylvania. For interoperability and compatibility reasons, it is important that the spare transformer continue to be from R.E Uptegraff whether as a rebuilt or a new unit. This would greatly facilitate and ensure the seamless future integration of the spare unit into the working lineup after removing another unit from service. Therefore it is proposed that R.E. Uptegraff be considered as a sole source vendor of proprietary materials per District Code Section 3.08. The District has received firm quotes from the original manufacturer, R.E. Uptegraff, for both the refurbishment and replacement options for the failed transformer (copy attached). The cost to rebuild the failed transformer is $79,458 with a turnaround time of 16 to 18 weeks. The cost to purchase a brand new transformer is $107,696 with a delivery time of 22 to 24 weeks. Since the refurbishment cost is less and lead time is significantly less than the purchase of a new unit, the advantages of rebuilding the failed transformer make this the better of the two options available. The rebuilt transformer would be identical to the other Uptegraff substation transformers at Truckee Substation. 4. FISCAL IMPACT Sufficient funds exist within the Electric Capital Replacement Fund for the rebuild and refurbishment of the failed substation transformer. The District has submitted a claim to our insurance provider for the damages at Truckee Substation due to the windstorm event. There will be some proceeds available from the insurance coverage although the payout amount and timing are not known at this time. 5. RECOMMENDATION a) Dispense with the competitive bidding process necessary to rebuild and refurbish the failed substation transformer per District Code Section 3.08 - Sole Source Vendors. b) Authorize the General Manager to proceed with the rebuild and refurbishment of the failed substation transformer by entering into a contract with R.E. Uptegraff in the amount of $79,458, plus a 10 percent change order allowance in the amount of $7,946 for an amount not to exceed $87,404 plus tax. c) Authorize a transfer of up to $87,404 plus tax from the Electric Department Capital Replacement Fund to the Electric General Fund. d) Direct that the proceeds from the insurance coverage for the incident at Truckee Substation be deposited into the Electric Department Capital Replacement Fund. Stephen Hollabaugh Assistant General Manager Michael D. Holley General Manager