New research suggests that Bitcoin mining produces as much as 30,700 tonnes of e-waste every year.
The research, published in the journal Resources, Conservation & Recycling, suggests this is comparable to small IT equipment waste produced by countries like the Netherlands.
The Science Direct study said: “E-waste represents a growing threat to our environment, from toxic chemicals and heavy metals leaching into soils, to air and water pollution caused by improper recycling.”
Miners earn money by creating new Bitcoins and the computing used to do this consumes vast amounts of energy. The miners audit Bitcoin transactions in exchange for an opportunity to acquire the digital currency.
Previously, attention has been specifically focused on the electricity this consumes – currently more than the Philippines, according to reports by the BBC – and the greenhouse gas pollution caused as a result.
E-waste represents a growing threat to our environment, from toxic chemicals and heavy metals leaching into soils, to air and water pollution caused by improper recycling
But the computers that are used for mining quickly become obsolete – this also generates lots of e-waste.
The researchers estimate Bitcoin mining devices have an average lifespan of only 1.29 years.
With electricity being a main cost for Bitcoin miners, they have sought out ever more efficient processors, which has seen a move to highly specialised chips called Application-specific Integrated Circuits (ASICs).
However, ASICs are so specialised that, as they become obsolete, they cannot be “repurposed for another task or even another type of cryptocurrency mining algorithm”, the researchers write.
But while the chips can’t be reused, much of the weight of Bitcoin mining equipment is made up of components such as “metal casings and aluminium heat-sinks” which could be recycled.
The UN reports that e-waste is the world’s fastest-growing waste stream, up 21 per cent between 2014 and 2019 to 53.6 million metric tonnes and less than one-fifth of that is recycled.
To reduce the e-waste generated from Bitcoin, a new mining method called ‘proof-of-stake’ should be encouraged, the report states. It says this is more energy-efficient than the ‘proof-of-work’ principle used by bitcoin and can be performed on regular computers.