Confronting the Carbon-Footprint Challenge of Blockchain

The distributed consensus mechanism is the backbone of
the rapidly
developing blockchain network. Blockchain platforms consume vast amounts
of electricity based on the current consensus mechanism of Proof-of-Work
(PoW). Here, we point out a different consensus mechanism named Proof-of-Stake
(PoS) that can eliminate the extensive energy consumption of the current
PoW-based blockchain. We comprehensively elucidate the current and
projected energy consumption and carbon footprint of the PoW- and
PoS-based Bitcoin and Ethereum blockchain platforms. The model of
energy consumption of PoS-based Ethereum blockchain can lead the way
toward the prediction of other PoS-based blockchain technologies in
the future. With the widespread adoption of blockchain technology,
if the current PoW mechanism continues to be employed, the carbon
footprint of Bitcoin and Ethereum will push the global temperature
above 1.5 °C in this century. However, a PoS-based blockchain
can reduce the carbon footprint by 99% compared to the PoW mechanism.
The small amount of carbon footprint from PoS-based blockchain could
make blockchain an attractive technology in a carbon-constrained future.
The study sheds light on the urgency of developing the PoS mechanism
to solve the current sustainability problem of blockchain.