Cryptofarm: Hundreds of computers that calculate crypto currencies - and quickly end up in the trash
MAXIM ZMEYEV / AFP
The mountains of garbage are growing, and that also applies to hardware garbage: Since 2000, the annual amount of electronic waste has increased from 20 to 50 million tons worldwide. The United Nations University has calculated that it will double in the next 30 years. But not only televisions, smartphones and laptops have their part in the fact that toxic fumes rise into the atmosphere and mercury ends up in the garbage. Cryptocurrencies like Bitcoin are also apparently causing mountains of electronic waste to grow.
This scrap arises when, for example, the hardware that is used in so-called crypto farms for the production of Bitcoin has to be replaced. In such data centers there are rows of power-hungry special computers whose modern processors are optimized for calculating Bitcoin. If the hardware is out of date, it usually ends up in the trash, as the cards are rarely suitable for video games on the home PC.
For the study "The growing e-waste problem of Bitcoin", the scientists Alex de Vries and Christian Stoll calculated how much waste is generated in this way through the production of virtual currencies.
According to this, the electronic waste generated by so-called Bitcoin mining currently adds up to 23,000 tons per year.
This is the result if you take the current rate of the cryptocurrency, around 40,000 euros, as a basis.
272 grams of scrap per Bitcoin transaction
In their study, the researchers include the estimated computing power of the Bitcoin farms, the number of Bitcoin mined per day and the energy costs involved. In addition, the authors assume that the hardware used to mine Bitcoin will have an average lifespan of one year and four months. According to their models, this results in an amount of 272 grams of electronic waste per Bitcoin transaction in the blockchain. So that's roughly the equivalent of two iPhone 13 mini's that land in the trash. That is the equivalent of around half a million smartphones scrapped every day.
For the calculations, the researchers limit themselves to special mining hardware that is used exclusively for Bitcoin calculations.
Graphics cards designed for video games have not been taken into account because Bitcoin mining with conventional graphics cards is usually not profitable, says Christian Stoll from the Technical University of Munich and the Massachusetts Institute of Technology (MIT) to SPIEGEL.
"Bitcoin miners almost exclusively use so-called ASICs," says Stoll.
"This type of hardware is tailored to a specific purpose and can therefore not be reused for other applications."
There is also a more climate-friendly way
So far, energy costs have been the main focus of Bitcoin - reason for the authors to write the study. "People often forget that the Bitcoin network not only swallows a lot of energy, it also requires millions of highly specialized and short-lived devices," said Alex de Vries to SPIEGEL. "Our goal was to highlight the previously unmentioned part of the story." E-waste not only contributes to climate change with toxic chemicals that are released during incineration, but can also pollute the soil and groundwater if improperly disposed of, says de Vries.
The scientist's message: The method by which Bitcoin is generated should be changed.
So far, millions of so-called miners have been calculating new blockchain blocks, approving transactions and being rewarded with Bitcoin for this.
However, the computational effort for this work is immense.
According to de Vries, one should switch to the so-called "Proof of Stake" model, as is at least planned for the competing currency Ethereum.
The method is considered more climate-friendly.
The idea: Not everyone is counting on it wildly, but a random generator selects who is allowed to confirm a transaction.
If you own more cryptocurrency, your voice counts more with the model.
There is no worldwide betting.
In addition to reforming the Bitcoin algorithm, Christian Stoll also calls for a higher recycling rate. However, in his opinion, not all environmental efforts should focus on cryptocurrencies. Bitcoin is "only responsible for a small part of the global e-waste problem in absolute terms," says Stoll. "Incidentally, this also applies to the topic of electricity requirements."