Bitcoin surges above $40,000 after Elon Musk says Tesla will resume crypto payments when mining is cleaner

• Bitcoin climbed above $40,000 after Elon Musk suggested Tesla might accept it as payment again.
• Musk said he'll do it when there's proof of about 50% of mining energy used is clean.
• Tesla halted bitcoin payments last month over concern its mining process is damaging to the environment.

Bitcoin traded above $40,000 on Monday after Elon Musk tweeted Tesla would accept payment in cryptocurrency again once mining can be done using cleaner energy.

"When there's confirmation of reasonable (~50%) clean energy usage by miners with positive future trend, Tesla will resume allowing Bitcoin transactions," the billionaire said in a tweet.

He was responding to a Cointelegraph report that quoted Magda Wierzycka, a South African billionaire businesswoman and CEO of asset manager Sygnia, saying that Musk's bitcoin-related tweets should have led to a regulatory investigation.

According to Wierzycka, Musk deliberately pumped up bitcoin's value and then sold a chunk of his exposure at its peak. But the Tesla boss disputed this claim, saying "Tesla only sold ~10% of holdings to confirm BTC could be liquidated easily without moving market."

Bitcoin saw further gains after billionaire Paul Tudor Jones said on CNBC he likes the digital asset as a portfolio diversifier. " The only thing I know for certain, I want 5% in gold, 5% in bitcoin, 5% in cash, 5% in commodities," he said on Monday.

The cryptocurrency was last trading 13% higher around $40,700 on Monday as of 9:35 a.m. ET, and it is up 40% so far this year.

"The charts suggest consolidation followed by a rally through $41,000 targets further gains to around $44,000," Jeffrey Halley, a senior market analyst at OANDA, said.

Musk revealed in February his electric car company invested $1.5 billion in bitcoin and that it would start accepting it as payment for its vehicles. Barely three months later, Tesla made a U-turn and stopped payment in bitcoin because of how energy-intensive the mining process is.

"We are concerned about the rapidly increasing use of fossil fuels for bitcoin mining and transactions, especially coal, which has the worst emissions of any fuel," Musk said in a tweet at the time.

It isn't clear yet how Musk will gather data to assess bitcoin's clean energy use. But he previously suggested that the cryptocurrency can rid itself of its negative environmental image if top miners prove they're using greener energy by posting audited data on renewables used.

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