Bitcoin miners in the Lone Star State are powering down this week as a punishing heatwave stresses the power grid. Texas’ grid operator asked residents and businesses to conserve energy on Monday with “extreme hot weather driving record power demand across Texas.”

Bitcoin mining companies in the state responded by turning off their machines that otherwise would have used over 1,000 megawatts of electricity, according to the Texas Blockchain Council. That freed up about 1 percent of the grid’s total capacity.

“They are shutting down for several reasons but primarily because it is the right thing to do to be a good ‘grid citizen,’” Lee Bratcher, president of the Texas Blockchain Council, said to The Verge in an email. There are also financial motives, Bratcher said, since spot prices for electricity in Texas skyrocket when power is in short supply.

Bitcoin miners have flocked to Texas over the past year after China banned the practice, and the US subsequently became the biggest hub for mining globally. Those crypto miners are expected to inflate electricity demand in Texas by up to 6 gigawatts by the middle of next year, according to Bloomberg.

Crypto mining companies essentially set up their own data centers filled with specialized hardware that “mine” Bitcoin by racing to solve ever more complex puzzles. That energy-intensive process is done to validate new transactions on the blockchain and allows miners to earn new tokens.

The Bitcoin network, as a result, uses more electricity annually than the country of Belgium. Its energy use, however, is estimated to have dropped over the past month after the price of Bitcoin took a nosedive. A lower value for the cryptocurrency, combined with high energy prices, makes it less profitable to run mining machines. In Texas, one “large publicly traded miner” plans to shut off between 8AM and 10PM for “several days this week,” Bratcher said.

Powering down, especially during those peak hours, also helps Texas’ power grid avoid potential outages. Hot temperatures typically place more pressure on electricity grids as people blast their air conditioners, and Texas is seeing triple-digit heat this week. The heat dome suffocating Texas has also starved it of much of its wind power, which typically generates about a quarter of its electricity. Texas’ power grid is also particularly vulnerable because it doesn’t connect to power grids in other regions. Other states can usually share energy with each other in an emergency.

The state has so far avoided large power outages after the Electric Reliability Council of Texas, or ERCOT, asked Texans to voluntarily reduce their power consumption on Monday. Back in February 2021, a deadly cold snap caused massive outages across the state. Stifling temperatures are forecast to continue throughout the week in Texas, so its power grid isn’t out of the woods yet.

This isn’t the first time that Bitcoin miners in the state have responded to a power crunch during high temperatures, and it probably won’t be the last. Riot Blockchain, a Bitcoin mining company, curtailed 8,648 megawatt-hours of energy consumption throughout June, Riot marketing coordinator Alexis Brock said in an email to The Verge. That’s significant because Riot operates a facility in Rockdale, Texas which it claims is North America’s biggest Bitcoin mining facility. The company plans for the facility to continue to ramp down as needed this summer when peak power demand threatens the stability of the grid.