Bitcoiners mining cryptocurrency at home this winter have been staving off freezing temperatures by putting them to good use as heaters.

According to the Wall Street Journal, crypto miners in France and the United States report their overall heating costs have dropped  — even if the temperature in their homes often gets far above what they’d prefer.

Thomas Smith, a photographer based in California, has been using mining rigs to heat his home since at least 2019. He’s also been exploring some novel uses, including employing the miners to warm up his two chickens in an outdoor coop and to grow tomatoes in his greenhouse as temperatures started plunging at night.

It’s not the first time the idea has been implemented, with reports in 2018 that the co-founder of Czech cryptocurrency exchange NakamotoX had been growing ‘cryptomatoes’ in five-acre greenhouse using the excess heat from crypto mining.

“My greenhouse is 24 cubic feet, so putting in all the heat from the cryptocurrency-mining computer would increase its temperature by around 40 degrees,” said Smith in the WSJ. “Even in the dead of winter — with a nighttime temperature of 45 degrees — that would still push my tomatoes to their 85-degree limit. On warmer nights, it would risk roasting them on the vine.”

He added:

“I’ve experimented with heating my home using cryptocurrency-mining waste heat on a small scale, with a good deal of success”

Before the pandemic, when many were allowed to live on university campuses in the United States, students reported mining with “free” electricity provided by the schools, which helped them cover utility bills. One dormitory resident advisor said at the time that instead of using a space heater in the winter, he would simply mine crypto.

But before you rush off to save on heating bills with a crypto mining rig, remember that it’s difficult to take advantage of mining many cryptocurrencies at home as the cost of electricity often makes using personal computers to generate blocks financially prohibitive, especially for ultra-competitive currencies like BTC.