Energy Consumption

Energy consumption, in a crypto context, refers to the electricity used by blockchain networks — overwhelmingly by proof-of-work mining, where the security model deliberately ties trust to expended power. Because miners compete by running hardware around the clock, a large network like Bitcoin draws electricity on the scale of a mid-sized country, a figure researchers estimate from network hash rate and the efficiency of common mining machines.

The clearest contrast is Ethereum's 2022 switch from proof of work to proof of stake, which cut that network's electricity use by an estimated 99.9% or more, since validators only need ordinary computers to propose and attest to blocks. This is why energy debates today center almost entirely on Bitcoin and other proof-of-work chains, not on blockchains generally.

A common misconception is that each individual transaction "costs" a fixed, enormous amount of energy; mining power secures the whole chain and does not scale with transaction count, so per-transaction figures are misleading. The energy question has real nuance on both sides: critics point to carbon emissions where miners use fossil-heavy grids, while miners increasingly seek stranded or surplus power — flared gas, curtailed renewables, off-peak hydro — because cheap electricity is their dominant cost. Some grid operators also pay miners to shut down during demand spikes, treating them as flexible load. Where the balance lands depends heavily on the local energy mix.