Quantum computers could slash the energy use of cryptocurrencies

Quantum computers could be used to mine existing cryptocurrencies like bitcoin or future, more energy-efficient ones, slashing their electricity use, according to two new analyses.

Cryptocurrencies that rely on a “proof of work” method perform computationally intensive calculations to produce new coins and certify transactions, at great energy cost. Some networks have moved to less power-hungry techniques, like Ethereum’s “proof of stake”, but bitcoin, the world’s largest cryptocurrency, still runs on proof of work and consumes 0.5 per …