This story was updated at 2:15 p.m. EDT.
Democratic lawmakers today are renewing calls for federal agencies to force cryptocurrency mining firms to disclose their emissions and energy use, after an investigation revealed that major firms in the United States are using power on par with major cities.
Massachusetts Sen. Elizabeth Warren and California Rep. Jared Huffman disclosed today that their inquiry into seven cryptocurrency mining firms operating in the United States showed that they use 1,045 megawatts, or the same capacity required by Houston, which has a population of 2.3 million people.
The lawmakers likewise revealed that the cryptomining process results in carbon emissions of at least 1.6 million tons annually and increases energy prices for other consumers.
“The results of our investigation, which gathered data from just seven companies, are disturbing, with this limited data alone revealing that cryptominers are large energy users that account for a significant — and rapidly growing — amount of carbon emissions,” Warren and Huffman wrote in a letter to Energy Secretary Jennifer Granholm and EPA Administrator Michael Regan.
Sens. Sheldon Whitehouse (D-R.I.), Ed Markey (D-Mass.) and Jeff Merkley (D-Ore.) and Rep. Rashida Tlaib (D-Mich.) also co-signed the missive.
The lawmakers went on to press the Biden administration to use “all available authorities at your disposal,” including the Clean Air Act, to require cryptocurrency mining firms to disclose their emissions contributions and energy use.
“Our investigation suggests that the overall U.S. cryptomining industry is likely to be problematic for energy and emissions. But little is known about the full scope of cryptomining activity,” the letter continued, noting that the seven firms reviewed are expected to increase their capacity by 230 percent in the near future, or enough additional energy to power a city of 1.9 million residences.
Warren and others published the data collected from the cryptocurrency firms.
Cryptocurrency mining typically involves high-powered computers that solve puzzles. It uses intense amounts of electricity. Crypto mining operations have often turned to coal and other fossil fuels to power their efforts (Greenwire, Jan. 18).
The Energy Department did not immediately return a request for comment, but Granholm indicated earlier this year that she would be open to tracking the total number of cryptocurrency miners in the United States along with their energy use.
EPA spokesperson Shayla Powell told E&E News: “We have received the letter and will respond through appropriate channels.”
“It is critical to understand the strains upon the grid,” Granholm told Warren at a Senate Armed Services Committee hearing in May (E&E Daily, May 20).
Republican lawmakers, including House Financial Services ranking member Patrick McHenry (R-N.C.) and Sen. Cynthia Lummis (R-Wyo.), have urged EPA to hold back on implementing any restrictions on crypto mining, arguing that the industry’s economic benefits would be at risk (E&E Daily, June 22).
Some of the companies surveyed by Democrats have sought to frame their activities as environmentally friendly.
“Bitcoin mining is uniquely beneficial and supportive of renewable energy generation and resilient power grids,” Colorado-based firm Riot Blockchain wrote to lawmakers. “This fact, along with the technological advancement, job creation, and social and economic value that Bitcoin mining is creating — right here in the United States — means that the industry currently is, and must be, a part of the solution.”
The firm highlighted its use of hydropower for its Coinmint facility, which relies on 51 MW from the Moses Saunders dam in St. Lawrence County, N.Y.
But lawmakers noted that its much larger Whinstone facility uses energy from the Texas grid, where 63 percent of generating capacity is powered by coal and natural gas.
The New York-based Greenidge Generation Holdings likewise touted its reliance on natural gas, noting that a Torrey, N.Y.-facility it owns and operates was once a coal-fired power plant.
“The Facility has never operated on coal under Greenidge’s ownership, and it will never burn coal again,” the company wrote to lawmakers.
It also touted its commitment to purchase carbon offset credits: “Regarding its efforts to offset its carbon footprint, Greenidge plans to continue to offset 100 percent of the carbon emissions associated with its mining operations at the Dresden facility and future locations.”