Let me freak you out for a second. You know what bitcoin is, right? I mean, no, but quickly, it’s a “cryptocurrency” that’s basically secret computer money. One bitcoin, which doesn’t actually have a real, physical form, is worth at this moment upwards of $16,000. But to get one, you either have to buy them from online exchanges or use specialized computing hardware to “mine” it. That last bit is where the freak-out comes in.
In a report last week, the cryptocurrency website Digiconomics said that worldwide bitcoin mining was using more electricity than Serbia. The country. Writing for Grist, Eric Holthaus calculated that by July 2019, the Bitcoin peer-to-peer network—remember BitTorrent? Like that—would require more electricity than all of the United States. And by November of 2020, it’d use more electricity than the entire world does today.
That’s bad. It means Bitcoin emits the equivalent of 17.7 million tons of carbon dioxide every year, a big middle finger to Earth’s climate and anyone who enjoys things like coastlines, forests, and not dying of mosquito-borne diseases. Refracted through a different metaphor, the Bitcoin P2P network is essentially a distributed superintelligence utterly dedicated to generating bitcoins, so of course it wants to convert all the energy (and therefore matter) in the universe into bitcoin. That is literally its job. And if it has to recruit greedy nerds by paying them phantom value, well, OK. Unleash the hypnocurrency!
The idea of bitcoin still has the whiff of genius—a digital currency as untraceable and trustworthy as cash, unfettered from nationality and physicality, with egalitarianism and access built into its philosophical and technical firmware. But the reality, exposed by bitcoin’s remarkable run-up in value over the last three months, is that the science may not hold together. Which isn’t to say people aren’t trying to fix it.
The thing that makes Bitcoin bitcoiny is the blockchain, the secure ledger of all payments and trades. The point of the P2P bitcoin network is the generation and maintenance of that ledger, and technically anyone can contribute updates—those recordings of transactions are blocks in the chain. But there’s a catch. (This was the bit of genius in bitcoin inventor Satoshi Nakamoto’s pitch, whoever the almost certainly psuedonymous “Satoshi Nakamoto” is or are.) In order to contribute a block, you also have to solve some really hard math, a “hashing algorithm” called SHA-256.1
Validate a bunch of transactions and do the math, and the system might choose your block to add to the chain; if it does, you win some bitcoin. That’s called mining, and the idea of imposing a cost to enter—that hashing math—is “proof of work.”
“The nice thing about proof of work is that there is no admission step,” says Emin Gün Sirer, codirector of the Initiative for Cryptocurrencies and Smart Contracts at Cornell University. “If you can come in and suddenly start solving these cryptographic puzzles at the heart of it, you can contribute to the upkeep of the ledger.”
You can’t trick your way into solving that math. The SHA-256 algorithm is designed, intentionally, to be so hard that it requires brute-force computing. Try as many computational answers as you can, as fast as you can. Which means you have to keep your computer turned on all the time, running the fan to cool off your hot, overclocked processor. “The energy consumption is a security feature. It’s a good thing,” Sirer says. “To take over the system, you’d have to spend at least as much as what the system is spending now. You have to own 51 percent of all the hashing power.”
https://www.wired.com/story/bitcoin-global-warming/