Warren Targets 6 More Crypto Miners for Their Energy Use

The crypto miners welcomed the dialogue on the environmental issues of mining with the Massachusetts senator.

AccessTimeIconJan 28, 2022 at 12:06 a.m. UTC
Updated Apr 9, 2024 at 11:34 p.m. UTC

U.S. Sen. Elizabeth Warren (D-Mass.) expanded her inquiry of bitcoin miners’ energy usage and their environmental footprint, sending letters to six more miners on Thursday.

  • Warren wrote to Riot Blockchain, Marathon Digital Holdings, Stronghold Digital Mining, Bitdeer Group, Bitfury Group and Bit Digital, questioning their “extraordinarily high energy usage.”
  • In December, Warren, who has made environmental issues a focus of her office, sent a letter to the bitcoin miner Greenidge Generation, expressing her concerns about its high energy usage.
  • In the new letter, Warren and her colleagues asked each miner to detail its electricity consumption, scaling plans, agreements with electricity companies and impact on energy costs for consumers and small businesses by Feb. 10.
  • “The extraordinarily high energy usage and carbon emissions associated with Bitcoin mining could undermine our hard work to tackle the climate crisis – not to mention the harmful impacts crypto mining has on local environments and electricity prices,” Warren said in the letter.
  • The correspondence adds to a list of inquiries by lawmakers globally on the energy consumption of proof-of-work (PoW) mechanisms that reward crypto miners for validating transactions. Most recently, the U.S. held a congressional hearing to discuss the energy consumption related to the PoW. Meanwhile, the European Union's markets regulator called for a ban on the validation system, citing its energy intensity.
  • "We are encouraged to see that they are interested in learning more about Marathon and the broader bitcoin mining industry, and we welcome the opportunity to participate in the educational process," said Charlie Schumacher, Marathon's director of corporate communications in an email to CoinDesk. "We look forward to having a productive dialogue about the many benefits that we and the rest of our industry have for the United States," he added.
  • "As a company that is first and foremost tackling a legacy environmental problem left over from the coal industry, any discussion that sheds light on the impact facing Pennsylvanians in relation to their water, land and community is important to us," said a spokesperson for Stronghold Digital, a bitcoin miner who converts coal waste across Pennsylvania into power for mining operations.
  • Stronghold has received bipartisan support within Pennsylvania and its two facilities, Scrubgrass and Panther Creek, will convert a total of 1.25 million tons of waste coal to alternative energy annually, the company spokesperson said, adding that Stronghold welcomes any dialogue on the environmental issues with Senator Warren and her colleagues.
  • Meanwhile, another mining company targeted by Warren, Bit Digital, also welcomed talks with the lawmakers, noting that the company has taken a "leadership role" to achieve energy sustainability within the crypto mining sector. "We welcome this sort of high-level dialogue with policymakers in Washington and at all levels of government, and look forward to responding to this inquiry in a timely and informative manner,” said Bryan Bullett, CEO of Bit Digital.
  • The willingness to engage with policymakers was also echoed by Riot Blockchain. "We look forward to thoroughly reviewing and earnestly responding to the requested information in the letter we received from the Senate," the company's spokesperson told CoinDesk.
  • Other two companies didn't immediately respond to request for comments.

UPDATE (Jan. 28, 2022, 17:40 p.m. UTC): Adds comments from Marathon, Stronghold and Bit Digital.

UPDATE (Jan. 28, 2022, 19:47 p.m. UTC): Adds comment from Riot Blockchain.


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Aoyon Ashraf

Aoyon Ashraf is managing editor with more than a decade of experience in covering equity markets