Georgia Power Battery Rating Could Tilt Grid Plan Toward Gas

ATLANTA, Ga. — A technical number buried in Georgia Power’s latest search for new electricity supply is becoming a point of contention as the state’s largest utility plans another large expansion of its grid.

Georgia Power wants to line up 2,000 to 6,000 megawatts of new dispatchable capacity to cover demand expected in 2032 and 2033. The utility asked the Georgia Public Service Commission to approve its bidding documents for that all-source request, which can include gas-fired generation, energy storage and batteries paired with renewables. Selected projects are due to go to the commission for certification in mid-2027.

The dispute centers on a measure called effective load carrying capability, which rates how much of a resource’s size can be relied on when demand peaks. Gas plants usually score between 60% and 80%. Solar or wind without storage can fall anywhere from 4% to 40%, and renewables paired with batteries can approach 95%.

In earlier planning, Georgia Power credited its first 3,000 megawatts of batteries at 95%, the next 3,000 at 75% and the following 3,000 at 50%. Clean energy groups that testified before state regulators say the current bid request credits storage at just 20%. Under that figure, a 1,000-megawatt battery would count as 200 megawatts of capacity, while a gas plant of the same size rated at 80% would count as 800.

The Advanced Power Alliance and the Southern Environmental Law Center argue that the lower rating makes batteries look far more expensive than gas and may have discouraged storage developers from bidding at all. Georgia Power has said its calculations have been consistent and that it cannot discuss specifics while procurements are under way.

The stakes are large because demand keeps climbing, fueled by data centers and wider electrification. The utility reports that 32 large-load customers have committed to about 15,600 megawatts of service, with 21 projects already under construction. Regulators approved roughly 9,900 megawatts of gas turbines, batteries and solar-plus-storage for the 2029-2031 period, about 6,000 megawatts of it gas.

Georgia Power and the commission are expected to discuss which projects advance early next year. Advocates say that if the battery rating is not changed this round, they will push for a higher value when the next planning cycle begins in 2028.

Filed under: Atlanta GA Business News