While folks in the Northeast find themselves staring down what could be a summer full of wildfire smoke, Texans are looking forward to hotter-than-average temperatures. And as people kick their air conditioners into high gear, demand on the state’s electric grid is expected to break records.

For the first time, Texas will be relying on wind and solar energy to meet peak demand. The problem is, those are variable sources — the sun isn’t always shining and the wind isn’t always blowing. In response, Texas has been adding batteries to its grid at a breakneck pace.

To power all the state’s air conditioners during peak demand, coal, natural gas and nuclear plants can no longer provide enough energy, according to Joshua Rhodes with the University of Texas at Austin.

“We are going to be relying on some amount of wind and some amount of solar to be producing electricity during certain times of the summer,” he said.  

But when the sun goes down, the wind isn’t blowing and people are still cranking up those ACs, “there is a bit of a lull in renewables that batteries would be great at filling.” 

As renewable energy has expanded in Texas, battery storage has grown about tenfold in two years, per Austin-based energy consultant Doug Lewin.

“We’re now up to just about 4,000 megawatts — roughly equal to the entire city of Austin,” he said. “And to see that kind of increase in that short time, in two to three years, is pretty extraordinary.”

But batteries still have a long way to go, said oil and gas consultant David Blackmon. “I’m not a Pollyanna about all this stuff,” he said.  

Batteries today can’t hold a charge when the power’s out for more than a few hours, he said, like when the Texas grid failed during a 2021 storm. 

“You need capacity that will provide electricity, as we saw in Winter Storm Uri, for days,” Blackmon said.

That technology exists, he added — but implementing it will take time and money.