Imagine two identical 100-megawatt generators. One runs at full output for an hour; the other runs for a day. Their rated capacity is the same. Their electricity production is not. This is the first distinction to make when an AI infrastructure announcement leads with megawatts.
Megawatts measure power: the rate at which electricity is produced or used. Megawatt-hours measure energy over time. The EIA explains that generation depends on both capacity and operating time. A generator operating continuously at 100 MW for 24 hours produces 2,400 MWh.
Our illustration is arithmetic, not a forecast. If the same hypothetical generator averages half its rated output over that day, production is 1,200 MWh. That could reflect a mix of reduced output and downtime; the number alone does not reveal the operating pattern. Neither example says how much electricity a particular data center will receive.
For an AI campus, translate a headline into three questions: what is the power rating, when does supply become available, and how much energy can actually be delivered across the hours the campus needs? A large announced figure without a delivery timetable leaves the operating question unanswered.
Keep generation and consumption separate, too. A plant’s output is not automatically a customer’s usable supply: delivery arrangements and facility requirements still need to be established. A useful reading habit is to write the unit beside every number before comparing two announcements. MW and MWh describe different things; combining them can turn an impressive headline into a misleading comparison.
Source: U.S. EIA: electricity generation and capacity. Definitions checked 27 October 2026. Calculations and illustrations by Capital Unpacked.
