A Controversial Bitcoin Mining Operation Has Made a New York Lake 'So Warm You Feel Like You're in a Hot Tub' Local residents say a power plant is heating Seneca Lake and emitting huge amounts of greenhouse gases.

Local residents have blamed bitcoin mining for heating up the largest of the Finger Lakes in upstate New York, with one saying it's "so warm you feel like you're in a hot tub," according to a report by NBC News.

Their complaints centre on a gas-fired power plant that's being used to power at least 8,000 bitcoin mining computers. The plant draws water from Seneca Lake for cooling, then discharges the warmed water back into the lake.

Bitcoin mining is the process by which new bitcoins are created. The mining is done by specialised computers that solve complex calculations on behalf of the bitcoin network.

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The power plant, Greenidge, which is being closely monitored by the Department of Environmental Conservation, is allowed to suck in 139 million gallons of water and discharge 135 million gallons daily. The discharged water can be as hot as 108 degrees in the summer and 86 degrees in winter, per permit documents viewed by NBC News.

"The lake is so warm you feel like you're in a hot tub," said Abi Buddington, who lives near the plant.

Private-equity firm Atlas Holdings bought the disused coal-powered site next to Seneca Lake, the largest of the Finger Lakes, in 2014, and reopened it as a natural gas plant in 2017.

At first the plant only generated energy for the grid when demand was high, but in 2019 Greenidge started using the plant to power bitcoin mining to make higher profits from surplus energy.

Bitcoin mining on computers uses huge amounts of energy. Last month Sen. Elizabeth Warren called for a crackdown on cryptocurrencies to fight the climate crisis.

Greenidge has at least 8,000 computers and is considering installing more as it plans to ramp up its bitcoin mining capacity to 45 megawatts by December, per NBC News' report.

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But this is leading to a huge spike in emissions. Regulatory documents viewed by environmental campaign group Earth Justice show that its carbon dioxide equivalent emissions and nitrous oxide emissions each grew nearly tenfold between January and December 2020 as it ramped up bitcoin mining.

Judith Enck, a former Environmental Protection Agency regional administrator, said that New York wouldn't meet its greenhouse gas emission reduction goals if Greenidge continued mining bitcoin.

Greenidge CEO Jeff Kirt told NBC News that "the environmental impact of the plant has never been better than it is right now," and that the facility was operating within its environmental permits. Greenidge said that it would make its operations carbon neutral by buying credits to offset its emissions.

Kirt told CNBC News that the plant has created 31 jobs. It has also donated $25,000 to the Dresden Fire Department and $20,000 to the school district, the outlet reported, and paid $272,000 to local authorities in lieu of real property taxes last year, according to an economic study commissioned by Greenidge.

But Peter Mantius, who writes a blog about local environmental politics, said that Greenidge pays "a fraction, maybe a quarter" of what the old owner paid because of a favorable tax assessment arrangement.

Greenidge's air permit is up for renewal in September, Mandy DeRoche, deputy managing attorney in the coal program at Earth Justice, told NBC News.

"We've asked the Department of Environmental Conservation to take a hard look and think about it as a new permit, not just a renewal," she said.

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