• Green blockchain technology has already made its way to the concerned minds of environmentalists.
• It happens to be a legitimate concern as blockchains, said to be the foundation of Web3, can consume enormous amounts of energy
• Carbon footprint can be reduced by careful consideration of various components of the network.

Green blockchain technology means ways how blockchains can be made environmentally sustainable mainly by developing a consensus mechanism and node networks to reduce the amount of electricity they consume or by exhausting green energy resources for blockchain execution. This comes as a cause of concern because blockchain technology is ever-increasingly finding its way to develop the inevitable Web 3.0.

Harnessing ways to establish a ‘greener’ blockchain

Researchers and developers have backed, that a conscious effort at a global level must be made to look for ways to develop green blockchain technology. Environmentalists have expressed concerns over the energy consumption of blockchain networks and rightly so. As good as technology is for advancing industrial development, there’s no denying that it requires a mass number of units involved to consume massive amounts of electricity.

Environmental advocates have even objected to the emerging decentralized tech simply for its giant Carbon footprint. Blockchain enthusiasts were at odds with them dismissing the concerns, for it can’t be refused that blockchain forms the bedrock of Web 3.0. Hence, it leads to a quest for more environment-friendly blockchain networks to make the highly anticipated Web3 sustainable.

The characteristic of a blockchain that leads to about 95% of its power consumption is its consensus mechanism. A consensus mechanism is a way to secure, verify and update new transactions on the network, i.e., to add a new block in the chain. An ideal green blockchain would, be the one whose consensus mechanism does not lead to sizeable energy consumption that causes greenhouse emissions.

The case is that either the blockchain network shouldn’t consume huge amounts of energy to process or the users of the particular blockchain must consciously decide how to use exclusively green energy.

Earlier blockchains, specifically Bitcoin, use a proof-of-work (PoW) consensus mechanism the miners need to compete with each other to find the hash algorithm by solving complex mathematical equations. Hashing is an energy extensive process, and then the miners have to engage in competition because the first one to solve the equation gets to be the one to add the block of new Bitcoin.

Since the winning computer earns a reward, it leads the participants to procure more and more highly specialized energy-consuming software. Due to significant energy costs, miners look for the cheapest sources of energy, albeit fossil fuels. According to Digicomist, the carbon footprints of Bitcoin are close to that of an entire nation.

A solution can be designing consensus mechanisms that are secure and don’t require consequentially huge hash computations. One such consensus mechanism is proof-of-stake (PoS). Majority of the blockchains that are currently active use a proof-of-stake consensus mechanism or one of 20 other mechanisms that don’t consume as much energy as proof-of-work. Only 10% of active blockchains use the PoW mechanism.

Interestingly, Ethereum, which initially started to operate on the PoW mechanism, did a “Merge” upgrade in May 2022 to shift to the PoS mechanism. As a result, its energy consumption fell from 90 TWH (approx. avg.) per year to 2.6 MWH (approx. avg.) per year. Some of the most eco-friendly blockchains other than Ethereum are — Cardano, Nano, Stellar Lumen, Solana, Polkadot, Algorand, and XinFin.