Agenda - Public Works Committee - 05/17/2022

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Public Works Committee Meeting Date: 05/17/2022 By: John Nelson, Engineering/Public Works Title: Selection of a Backup Power Supply for Water Treatment Plant 5. 5. Purpose/Background: Purpose: The water treatment plant will require back up power to keep the plant operational in the event of a power outage. The design team has determined that the full power load of the water treatment plant will be approximately 1300kw, for which there are two options for a backup power supply. Option: 1 Generator sized for emergency backup power only Option: 2 Generator sized for peak shaving demand as determined by Connexus Energy Option 1: is a tier 2, diesel powered generator, sized to run the most critical parts of the plant such as, SCADA, high service pumps, lights etc. Estimated prices for a tier 2, 1000kw generator are: Caterpillar $400,000.00 Cummins $300,000.00 Option 2: would require a tier 4, diesel powered generator, capable of 100% load of the water treatment plant. This size generator wouldn't be considered an emergency generator, because we would be able to peak shave power with Connexus Energy up to once a month. How the peak shaving program works is Connexus Energy would notify us that we must transfer all power to the generator. This request would be made no more than 12 hours per day or 300 hours per year. A tier 4 generator would have to meet all of the current requirements for emissions and would require a custom outdoor enclosure, which would increase the cost substantially. Estimated prices for a tier 4, 1500kw generator are: Caterpillar $1,400,000.00 Cummings $1,200,000.00 Timeframe: 20 Min. Observations/Alternatives: Observations: The peak shaving program would credit us $18.68/kW during the time of the required peak shave, but there are also penalties involved. Say if our generator were not to start/or was being maintained at the time when Connexus asked us to peak shave, the penalties would be as follows: If for any reason, the switch or generator fails to operate or the members load fails to transfer when dispatched by Connexus Energy, the member shall receive no credit and a penalty may apply. If the member's generation fails to operate more than three times during the year, Connexus Energy has the right to remove the member from the Generator credit rider Funding Source: The generator through the utility enterprise funds Recommendation: