What will keep Texas’ electricity grid humming? Big battery farms, salt caverns
Texas is a leader in wind power and is quickly growing its solar capacity. The state, however, has fallen short in the newest green energy frontier: storage.
Although it trails California and other early adopters, Texas is quickly adding more storage to make the state’s electricity grid more stable and reliable. That, experts say, could potentially undercut some natural gas plants years in the future.
Texas’ newest utility-scale battery-based electricity storage facility was approved in August, and work started in the fall on another 20 megawatts’ worth of batteries at West Texas wind energy plants. There’s also a much larger, low-tech storage option deep underground expected to open in the summer of 2020.
“Battery storage is still in its infancy,” said Steve Stengel, spokesman for Florida-based NextEra Energy, which owns the 30-megawatt Blue Summit battery that opened last year. “It’s something that we’re very focused on. We’re spending a lot of time studying it.”
These storage facilities provide electricity to the grid in fractions of a second to help keep it humming at a steady 60 hertz because large enough drops or spikes in frequency could lead to blackouts or damage equipment.
Texas is getting more and more power from wind and solar energy. But batteries aren’t cheap enough yet to use them to store excess renewable electricity, which can be unleashed when the sun isn’t shining or the wind isn’t blowing. Instead, storage is used for short bursts that keep the grid humming efficiently.
In 2016, the U.S. had 23.3 gigawatts of storage, or about 10 times the generation capacity of the Comanche Peak Nuclear Plant in Glen Rose, according to federal figures. A vast majority of that storage was connected to hydroelectric energy instead of batteries. And little of that storage — less than two-tenths of a percent — was in Texas.
The opening of Blue Summit, which is next to a NextEra wind energy plant, increased the state’s utility-scale battery storage significantly. And a nonbattery, compressed air storage project in the planning stages would nearly quadruple the state’s storage capacity.
For now, storage in Texas is another tool to keep the grid balanced. Eventually, it could play a role in undercutting certain natural gas plants called “peakers,” which are fired up on-demand to provide electricity during peak demand.
“If you think about how energy storage starts to take over the world, peaking is kind of your first big market,” Shayle Kann, a senior adviser to GTM Research and Wood Mackenzie, said at a December 2017 conference.
GTM Research/Wood Mackenzie research projected that electricity storage would compete against peakers in four years and always win the price battle in a decade.
Cyrus Reed, director of the Sierra Club Lone Star Chapter, wrote hopefully about that possibility in September.
“The promise of storage is also that Texas — and other states — may be able to reduce and even eliminate the need for the use of fairly inefficient and dirty natural gas peaker plants by charging up batteries during low use times and releasing the energy during peak energy use times,” he wrote on the website of Cynthia and George Mitchell Foundation.
Peakers have helped meet demand as Texas integrated more renewable energy into its mix. Wind provided more than 17 percent of the state’s electricity in 2017 and is expected to pass coal within a couple of years.