How a change in code can cut Bitcoin energy consumption by 99% (2024)

Bitcoin mining is a huge guzzler of power, with the entire network consuming more electricity than several small nations. As Bitcoin prices are starting to trend upwards once again, the popularity of the world’s cryptocurrency has led to several fossil fuel energy plants coming back to life at the expense of the environment. But the solution to Bitcoin’s energy problems may be something as simple as a change in the underlying blockchain code.

A new campaign called “Change the Code Not the Climate” by the Environmental Working Group, Greenpeace USA and other climate groups is asking the Bitcoin blockchain to switch from a “proof-of-work” model to a “proof-of-stake” model.

“If only 30 people — the key miners, exchanges, and core developers who build and contribute to Bitcoin’s code — agreed to reinvent proof-of-work mining or move to a low-energy protocol, Bitcoin would stop polluting the planet,” the campaign stated.

The “proof-of-work” model is a consensus mechanism that requires all computers on the blockchain network to execute complex mathematical calculations to decrypt the secured transactions occurring on the blockchain. It, therefore, requires a large amount of computing power to sustain operations.

Every time the transactions are processed, they are added to a ‘block’ on the blockchain. For each block processed, miners are rewarded a fixed amount of crypto for contributing to the blockchain through their computing power.

In the “proof-of-stake” mechanism, a blockchain user can become a transaction validator by pledging a part (or all) of their token holdings towards the development of the blockchain. In return, the user is rewarded with a fixed percentage of the pledged assets as rewards when a new block is added to the blockchain. This process is called the ‘staking’ of crypto assets. Since every holder of the token can become a validator, and spread the workload, the consequent energy requirements for the blockchain are reduced dramatically.

Ethereum, which is the second-largest cryptocurrency in the world, will soon be switching to the PoS model, which is expected to bring down its energy consumption significantly. Currently, the blockchain uses around 113 terawatt-hours of electricity per year, around the same as the Netherlands, but switching to the PoS model is expected to reduce its energy costs by 99 percent.

Several other major blockchains were developed from the ground up being PoS systems. These include Cardano, Avalanche, Polkadot and Solana among others.