A mostly-dormant coal power plant near Seneca Lake in New York was converted to natural gas in 2017 and began devoting much of its power generation to mining Bitcoin in 2019. The plant went from generating a total of 39,406 tons of carbon emissions in 2019 to generating a total of 243,103 tons in 2020, its first full year mining Bitcoin — the equivalent of the emissions that would be produced to provide electricity to around 35,000 households. The plant was operating at only 13% of its capacity in 2020, but has plans to increase its mining operations. Locals who enjoy Seneca Lake for swimming and other leisure activities have said that, due to the plant, Seneca Lake is now "so warm you feel like you're in a hot tub". This is because the plant circulates around 135 million gallons of water a day from the lake to the cool the plant, outputting water directly into the lake at allowed temperatures up to 86–108˚F (though the plant claims its average outflow temperature is 50˚, only 7˚ warmer than the inflow temperature).
Locals of the area have demanded that the Department of Environmental Conservation review the air emissions permit for the plant rather than renew an old one, which the DEC agreed to do, though they have delayed a new decision until March 31. Many pressing for permit review were unhappy with the delay, with the Seneca Lake Guardian reporting, "This delay from the DEC is not benign... Every day that Gov. Hochul and Commissioner Seggos drag their feet on this (permitting) decision is another day for Greenidge to continue expanding operations."
On June 30, regulators denied Greenidge's request to renew their permit.