AEA is purchasing battery storage services for stabilizing hydro

Alan Bailey

for Petroleum News

During a Nov. 18 special meeting of the board of the Alaska Energy Authority the board approved resolutions to obtain battery energy storage services from Railbelt electric utilities, to stabilize oscillations in the turbines in the Bradley Lake hydroelectric power facility on the Kenai Peninsula.

Curtis Thayer, executive director of the Alaska Energy Authority, has explained to Petroleum News that Bradley Lake's 120-megawatt generation capacity was originally designed to be provided by three 40-megawatt generators but was actually built using two 60-megawatt generators. In the event of a sudden large change in power generation or use in the Railbelt, the two-generator configuration at Bradley Lake is susceptible to oscillations that could cause damage to the power grid and, in an extreme case, to the Bradley Lake powerhouse itself.

In agreements that span 15 years AEA will pay utilities monthly fees for the battery services, using bond financing that can be used in support of Bradley Lake. Initially the agency is obtaining services from Homer Electric Association, Chugach Electric Association and Matanuska Electric Association. Fairbanks based Golden Valley Electric Association is currently in the process of obtaining its new battery energy storage system and, so, is not being requested for services at this point. Chugach Electric and MEA jointly own a new battery system and HEA has its own system.

Under the arrangements AEA will have priority over using the battery systems for dampening oscillations, should oscillations occur. AEA and the utilities are now engaged in developing the protocols required to provide the battery energy services in support of Bradley Lake, Thayer said.

There had been concerns about the possibility that the battery service arrangements might jeopardize federal tax credits associated with the battery purchase by Chugach Electric and MEA. However, this issue has now been resolved, Thayer said. Thayer commented that the agreements with the utilities amount to $28 million in funding for the battery services over the next 25 years, funding that will operate to the benefit of the electricity ratepayers. And this comes as part of strengthening the Railbelt electrical system, he said.

--ALAN BAILEY