Elon Musk says bitcoin can shake off its bad climate reputation if top miners prove they're using green energy

• Elon Musk said crypto miners should post audits of the renewables they use to erase concerns over bitcoin's energy use.
• He was responding to Ark Invest's research director who says bitcoin mining encourages green energy use.
• Bitcoin fell sharply to near $30,000 earlier this week after Tesla suspended bitcoin payments.

Elon Musk said on Thursday top bitcoin miners should post audited data of the renewable energy they possibly use in order to ease concerns over the digital asset's impact on the environment.

The billionaire was responding to a tweet from Ark Invest's director of research, Brett Winton, about bitcoin mining encouraging the adoption of renewables. The investment firm has argued bitcoin mining presents an opportunity to move away from fossil fuel consumption towards greener technology.

"I agree that this can be done over time, but recent extreme energy usage growth could not possibly have been done so fast with renewables," Musk said in a tweet. "This question is easily resolved if the top 10 hashing orgs just post audited numbers of renewable energy vs not."

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He went on to say energy used through bitcoin mining is beginning to exceed that of medium-sized countries. "Almost impossible for small hashers to succeed without those massive economies of scale," he added.

Bitcoin uses around 121.36 terawatt-hours (TWh) per year, according to Cambridge University research. For comparison, banking systems consume 263. 72 TWh, while gold mining takes up around 240.61 TWh. That shows the other two industries consume twice the energy of bitcoin mining.

Musk replied to another Twitter user who asked about the ideal consumption used in crypto mining, saying that even the less energy-intensive dogecoin had some room for improvement and that an ideal ratio would be 0.1 kWh "calculated as total energy used by system divided by max transaction rate."

Bitcoin recovered slightly to move back above $40,000, but it was last trading 2% lower around $39,650 on Friday. The coin's value fell sharply to just above $30,000 on Wednesday after Tesla suspended bitcoin payments, and China announced that digital tokens cannot be used as a form of payment.

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