Okay, so everyone talks about Bitcoin mining and how much power it uses. It’s a big deal, right? Well, a new study from Cambridge University just dropped some numbers that might make you look twice. They say the Bitcoin mining world is now getting over half its energy from clean sources. Like, 52.4% clean. That’s up from about 37.6% just a couple of years ago.
- A Cambridge University study reveals that over half (52.4%) of Bitcoin mining energy now comes from clean sources. This marks a significant increase from 37.6% just a few years prior.
- Natural gas has become the primary fuel for miners not using clean energy, while coal usage has drastically decreased. This indicates a shift towards less polluting energy sources.
- Bitcoin miners are increasingly helping power grids by acting as a flexible load, reducing power use when the grid is stressed. They are also exploring alternative revenue streams like AI computing and utilizing flared gas.
The folks at the Cambridge Centre for Alternative Finance (CCAF) put out this report. They looked at how 49 different mining companies get their power. These companies are spread across 23 countries and handle almost half of all the Bitcoin mining happening globally. It’s a pretty big chunk of the action they’re tracking.
Breaking down that clean energy bit, the report says about 9.8% comes from nuclear power (you know, the kind that doesn’t pump smoke into the air). The rest, a solid 42.6%, comes from things like wind and water power. Pretty neat, huh?
And here’s another interesting twist: natural gas is now the main fuel source for miners who aren’t using clean energy. It jumped from 25% to 38.2% since 2022. Meanwhile, coal, which everyone agrees is pretty dirty, fell way down. It went from 36.6% to just 8.9% in the same time. That’s a big shift away from the worst stuff.
The study estimates that the whole Bitcoin network uses about 138 terawatt-hours (TWh) of electricity a year. That sounds like a lot, and it is – roughly half a percent of all the power used worldwide. But the emissions are estimated at 39.8 megatonnes of CO2 equivalent. And get this, the machines miners use got about 24% better at doing the work for the same amount of power just in the last year. Efficiency matters.
What about all the old computers and gear? Miners reported that most of their old equipment, like 86.9% of it, gets a second life. It’s either sold off, used for something else, or taken apart to recycle the good bits. The study figured that Bitcoin mining created about 2.3 kilotonnes (that’s 2,300 tons) of electronic waste in 2024. Not nothing, but a lot of it gets reused.
Where is all this mining happening? Mostly in North America. The U.S. is the big player, doing about 75.4% of the mining they tracked. Canada is next at 7.1%. But the report also sees new spots popping up in places like South America and the Middle East, plus the usual suspects in Northern Europe are still at it.
Running these mining operations costs money, and electricity is the biggest bill by far. It makes up over 80% of what miners spend to keep the lights on and the machines humming. The average cost they reported for power was $45 for each megawatt-hour (MWh). When you add everything else up, it’s about $55.50 per MWh.
Here’s something you might not expect: these Bitcoin miners can actually help power grids. Sometimes, when everyone is cranking up their air conditioners or charging their cars, the grid gets stressed. Miners can act like a flexible load (they can turn down their power use quickly) to help balance things out. The report says they cut back their power use by 888 GWh in 2023 alone to help the grid operators. That’s like turning off a medium-sized power plant for a while.
But it’s not all smooth sailing. Mining companies are facing challenges. So, a lot of them are getting into other things, like running powerful computers for artificial intelligence (AI). They’re also getting smarter about energy, like using gas that would otherwise just be burned off (called flared gas) or capturing the heat from their machines to use for something else. It’s about finding new ways to make money and be more efficient.
Looking at the Energy Picture
Now, this Cambridge report comes out after another study, one led by Harvard researchers, that painted a pretty negative picture of Bitcoin mining’s energy use. That Harvard study got a lot of attention, but energy experts really pushed back hard, calling it “deeply flawed.”
The Harvard study, which showed up in a science journal, argued that Bitcoin mining in the U.S. was making air pollution worse. They claimed it exposed nearly 2 million Americans to more tiny particles in the air between mid-2022 and mid-2023. They tracked 34 big U.S. mines and said they used a ton of power, more than the city of Los Angeles, and that most of it came from fossil fuels.
But people who know this stuff well disagreed. Daniel Batten, who studies energy and sustainability, especially with Bitcoin, told a news site that the Harvard study looked like it started with the idea that “Bitcoin mining must look bad” and then just found data to support that. He said it used old ways of looking at things and picked data that fit the story, an approach that other researchers had already shown wasn’t right.
Another group, the Digital Assets Research Institute (DARI), also wrote a detailed response to the Harvard paper, pointing out similar problems. It seems like there’s a bit of a debate going on in the academic world about how to properly measure Bitcoin’s energy impact.
Batten pointed out that this isn’t the only time a negative study on Bitcoin mining has come out and then faced serious questions. He mentioned five others since 2022 that were often challenged because they used old information, relied on sources that weren’t great, quoted news articles instead of research papers, or only looked at certain data that fit their point.
The folks who wrote the Cambridge report touched on this too. They said that even though Bitcoin mining has grown fast, it’s been hard to get clear, real-world data. This often leaves people, including lawmakers and researchers, relying on old ideas or just stories they hear. It’s like trying to understand a fast-growing kid based on their baby pictures.
Alexander Neumueller, who works on digital assets energy at CCAF, said their report tries to fix this data problem. He said they talked directly to the people doing the mining instead of just using theories or old numbers. By looking at data from almost half the global mining activity, he hopes they can help everyone have a more solid, clear conversation about the industry and make better rules for it.
Still, the Cambridge authors were clear: this study is just the beginning. There’s more to learn about things like capturing methane gas, reusing the heat from mining machines, and how mining affects jobs and communities. They said keeping up with the data is key to making smart rules that allow for new ideas while still being good to the planet.
What About Tesla and Elon?
Remember back in 2021 when Elon Musk and Tesla seemed all in on Bitcoin? Musk even tweeted that buying Bitcoin was “inevitable.” Then Tesla bought a huge amount, $1.5 billion worth, to keep in their company’s accounts. They still hold a good chunk today, about 11,509 Bitcoin, which is worth around $1.1 billion right now. They bought it for an average price of $33,539, so they’re sitting on a nice gain.
A month after buying, Tesla announced you could buy their electric cars with Bitcoin in the U.S., and later, worldwide. Musk said Tesla was using its own software and running Bitcoin nodes (computers that help the network run) themselves. He even said they’d keep the Bitcoin they got from sales, not turn it into regular money.
But just two months later, things changed. With the price of Bitcoin dropping a bit, Musk announced Tesla was stopping Bitcoin payments. The reason? Concerns about the energy used for mining, especially the increasing use of fossil fuels like coal, which he called the worst for emissions. It was a sudden stop after a fast start.
Tesla said they’d keep their Bitcoin and would think about using it for payments again. The condition was clear: they needed “confirmation of reasonable (~50%) clean energy usage by miners with a positive future trend.” Musk tweeted this out later, setting a specific target for the mining world to hit if they wanted Tesla’s business back.
So, the new Cambridge study saying Bitcoin mining is now at 52.4% sustainable energy use looks pretty interesting next to Musk’s 50% target. It seems the industry has now passed the number he put out there a few years ago. Musk hasn’t said much about Bitcoin lately, though he did mention in a podcast in January that he still sees “some merit” in it and has a “soft spot” for Dogecoin because he likes dogs and memes. Go figure.
Even with the Cambridge report showing the mining world hit that 50% mark and then some, Tesla hasn’t announced they’re taking Bitcoin payments again. Will they? Hard to say. The Block news site tried to ask Tesla about it, but we haven’t heard anything back yet. It’s one of those things we’ll just have to wait and see on.
