Giant Batteries Helped the U.S. Power Grid Eke Through Summer (but some are skeptical they can make a big difference)

States rely more on batteries to avoid blackouts, with additional projects coming online soon

By Jennifer Hiller of The WSJ. Excerpts:

"The U.S. power grid relied on a new Band-Aid to help it through this summer’s punishing heat: giant batteries.

Battery storage has emerged as a tiny but important slice of the electrical-power mix during summer heat waves, helping bridge the gap at sundown when solar generation fades but everyone continues to crank air conditioners.

Electric-grid operators from Pennsylvania to California have skated through a season of high temperatures with a combination of existing and new energy supplies, including batteries, that have added up to enough to avoid rolling blackouts. Large-scale batteries have filled in when large power plants tripped offline and helped stabilize the grid.

In Texas, which saw 10 demand records this summer, batteries helped narrowly avoid rolling blackouts one evening at sunset. The state’s batteries discharge almost entirely in the evenings, especially around 7 p.m. when solar generation nosedives and there is little wind generation, which usually picks up overnight.

“Batteries weren’t the only reason why there haven’t been blackouts this year, but it was a critical piece of keeping the lights on,” said Jeff Bishop, chief executive of battery developer Key Capture Energy, which has about 380 megawatts of storage in operation in Texas."

"Companies connected nearly 1,500 megawatts of battery storage to the grid in the second quarter, enough to power about 300,000 homes during peak demand, up 60% from the same period last year, according to S&P Global."

"New tax incentives are speeding investment, too. Last year’s climate and tax bill, the Inflation Reduction Act, introduced a credit for battery storage for the first time. Batteries previously had to be paired with a solar or wind project to receive incentives but now can be built as stand-alone projects and qualify."

"Batteries earn money through providing services that stabilize the grid or by arbitrage, often charging up on cheap or excess renewable generation, then discharging later when energy prices and demand soar. Battery installations in the West might provide power for 3 to 8 hours, while those in the Midwest and Texas often discharge for an hour or two."

But see also Batteries Will Not Solve Renewable Energy Storage Problem, Says Royal Society by Chris Morrison, the Daily Sceptic’s Environment Editor. Excerpts:

"Current batteries cannot possibly store more than a fraction of the energy needed to keep the lights on when the wind stops blowing and the sun doesn’t shine. The learned U.K. Royal Society has recently analysed 37 years of wind patterns across Britain and concluded there is a serious underestimate of the amount of storage required."