Melding the electric-car maker’s fortunes with the energy-intensive cryptocurrency undercuts its purported mission.
Tesla Inc. has begun accepting Bitcoin as payment for vehicles in the U.S. This could be a clever marketing strategy, a way of bolstering the value of the company’s own crypto-bet, or perhaps just something to do. Maybe it’s all three. One thing it isn’t: compatible with Tesla’s green credentials.
“Mining” Bitcoin is energy intensive. The computers competing to log and verify the transactions underpinning, and securing, the cryptocurrency demand electricity — currently as much as used by the entirety of Finland, according to one estimate.
Unfortunately, most Bitcoin mining doesn’t happen in Finland, where power generation is low-carbon. Bitcoin miners, like any other miners, want to keep costs down — and China has some of the cheapest power in the world (roughly half Finland’s industrial tariff, for example). More than two-thirds of Bitcoin mining is believed to occur in China, where coal is the fuel of choice for generating electricity.
A common criticism of electric vehicles is that their plugs are ultimately tethered to fossil-fuel plants, making them less green than advertised. It’s a gotcha well past its prime: Even in China, a passenger EV will, on average, generate 38% lower carbon emissions over its lifetime than a comparable vehicle with an internal combustion engine.
Pay for that EV in Bitcoin, however, and things change — although not in a straightforward way.
It’s impossible to know the exact power consumption and carbon footprint of the Bitcoin mining sector. But Bank of America made some estimates in a report published earlier this month 2 . What was interesting about their analysis was the linkage between Bitcoin’s price and likely emissions.
As with anything else that gets mined, a rising price for Bitcoin attracts more miners. The resulting increase in network complexity is an essential security feature guarding against hackers (also attracted by those rising prices). But this means a corresponding increase in the computation rate of the network; it’s up by an estimated 60% over the past year alone, according to Blockchain.com 3 . This increasing complexity is a treadmill, and one which, despite more efficient mining hardware, causes energy consumption to keep rising.
Meanwhile, Bitcoin’s supply is both capped and in relatively few hands. New supply is designed to halve every four years, and an estimated 95% of the existing amount is controlled by less than 3% of accounts. Leave aside what this says about the actual usefulness of Bitcoin as a means of exchange as opposed to a coal furnace with a gambling habit. The point is that it means relatively small inflows of capital can move the price by a lot. BofA estimates a $93 million inflow would move the price up by 1%. In comparison, moving gold’s price by that much requires about $2 billion, BofA estimates.
So now consider Tesla. In February, the company announced it had put $1.5 billion into Bitcoin and was planning to let buyers transact with it. That sparked a renewed rally, ultimately taking the price of a Bitcoin from $40,000 all the way up to $60,000 (it’s bouncing around the mid-$50,000s now). By BofA’s calculation, a fresh $1 billion inflow would raise the price of Bitcoin by 11% — and the associated increase in electricity consumption by miners generates an extra 5.4 million tons of carbon emissions.
By the same math, a $1.5 billion inflow equates to 8.1 million tons. That is equivalent to the average life-cycle carbon savings of almost 238,000 electric vehicles in the U.S. — more than the estimated number of Model 3s produced in the U.S. last year. 4 The corresponding figure for China would be almost 475,000 EVs.
Now consider someone handing over one freshly minted Bitcoin today for a Model 3 with a performance upgrade (roughly $55,000 before incentives). The implied carbon footprint, under BofA’s math, is almost 300 tons — or almost nine times the estimated reduction in emissions for a vehicle of that sort over its lifetime.
In actuality, an individual driver using that Bitcoin isn’t directly using energy in the process (or it’s an immaterial amount). Similarly, a consumer buying a new Bitcoin for the sole purpose of turning around and handing it over to Tesla for a new car also wouldn’t on their own move the price of the cryptocurrency itself in a meaningful way.