The Homer Electric Association will begin construction this summer on the facility for a new battery energy storage system.
The battery energy storage system (BESS) will be capable of storing 93 Megawatt hours of electrical power that can be delivered to the grid at a rate of 46.5 megawatts per hour, according to HEA’s description of the project on their website.
Larry Jorgensen, HEA’s director of power, fuels and dispatch, said on Tuesday the system will allow for more consistent power delivery in the event a generator goes down or usage spikes unexpectedly.
“If you think of a power system as an equation that’s constantly balanced in real-time, the BESS will be beneficial because it can operate on both sides of the equation,” Jorgensen said. The storage system will be capable of substituting power generation for up to two hours at a time and will also be able to absorb excess energy that is produced.
In terms of cost, Director of Member Relations Bruce Shelley said on Tuesday that the project is being paid for through debt financing, but could not give specifics on how much it would cost due to a nondisclosure agreement.
The batteries are being purchased from Tesla. POWER Engineers, Inc. was awarded the contract for site engineering, according to HEA’s website. Representatives from Tesla did not respond to an email request for comment.
In a statement from HEA’s General Manager Brad Janorschke that was provided by Shelley, Janorschke said that costs for the project would not be reflected in the individual rates for HEA members until 2022.
Jorgensen said that the battery energy storage system will pay for itself “many times over” during years, such as 2019, when multiple outages occurred. Last summer’s Swan Lake Fire forced HEA to de-energize the transmission line that runs to Anchorage for several months, which essentially isolated the Kenai Peninsula from the rest of the utility rail belt.
While much of the extra power demand was met by the Bradley Lake Hydroelectric Dam during this time, Jorgensen said that being “islanded” in this way can potentially cost the utility company an extra $23,800 per day in additional fuel costs.
If HEA already had a battery energy storage system been in place, Jorgensen said, HEA system operations wouldn’t have had to change at all and HEA members would not be “at the mercy of being tied to Anchorage.”
The Golden Valley Electric Association, based in Fairbanks, installed a similar battery energy storage system in 2003 that is currently in operation. That system is much larger than what will be installed in Soldotna, Jorgensen said, and can only provide power for about 15 minutes.
The BESS will be located at the Soldotna Generation Plant at the corner of the Sterling Highway and Boundary Street.