Is it wrong that the electricity consumed by the bitcoin network is significant? Frankly, no. As we showed in the previous section, the electricity used is directly related to the value that users place on its block space.

Proof of Work is a brilliant invention by Adam Back, and an essential component to the bitcoin network. It has roots in defeating Sybil attacks and denial of service, and is what makes bitcoin economically unattractive to attack. Proof of work in bitcoin establishes a pay-to-use communications network, and assigns a cost to block space (bandwidth) that is directly related to the value that its users place on the ability to transact, via fees. Bitcoin miners provide a service, which they consume electricity to provide.

Proof of stake is an alternative method of establishing consensus in blockchains, but the outsized capital required to secure the network may be derived from ecologically costly means, and it has inherent centralizing forces that pose risks to the protocol over time.