lots of uncertainty on that, some experts say it's more like 40%. and is it "75% powered by renewables", or that 75% use some (but not all) renewables in their mix of energy? but even that lower figure is probably better than it soundsBitcoin is 75% powered by renewables anyway.
https://www.coindesk.com/everything-costs-energy-bitcoin-miningCoinDesk Research today published an expansive report on the wide-ranging environmental impacts of bitcoin mining titled “Does Bitcoin Have an Energy Problem?” in which its author, research associate George Kaloudis, addresses a wide array of energy concerns.
Kaloudis said bitcoin uses a relatively clean energy mix and there is meaningful investment into renewable-powered bitcoin mining. Kaloudis points out around 40% of mining energy is renewable and just over three-quarters of miners use renewables in their energy mix. By comparison, he said, the world uses around 20% renewable energy.
“Bitcoin provides a means to monetize wasted energy, improving the financial standing of energy companies, allowing for investment into clean energy production and transportation,” he said. “Bitcoin uses a lot of energy, but it is not an environmental disaster. Since the cheapest energy sources are typically stranded renewables, bitcoin’s growth trajectory is predicated on the expansion of renewable energy production.”
Investment in bitcoin mining has trended, in fact, toward using more renewables. A study from digital asset management firm CoinShares examined the bitcoin mining network and claimed that the Bitcoin network gets 74.1% of its electricity from renewable sources such as wind, solar and hydropower.