People today worry about data center power use, so here's a little history from one of the earliest computers: "With minimal cooling technology – two 20-horsepower blowers – ENIAC raised the room temperature to 50ºC when in operation and its 160kW energy consumption caused blackouts in the city of Philadelphia."
https://www.datacenterdynamics.com/en/analysis/eniac-at-75-a-pioneer-of-computing/