Why Nuclear Plants Run Flat Out: Capacity Factors

Nameplate capacity is not energy. Nuclear plants in the United States average about 92 percent capacity factors thanks to 18 to 24 month fuel cycles and short refueling outages of 30 to 40 days.

Hydro runs 30 to 50 percent depending on rainfall, wind about 35 percent offshore and 25 to 35 onshore, and solar tracks 15 to 25 percent with the sun. Gas peakers can sit under 15 percent by design, running only when prices spike.

That is why a 1,000 MW nuclear unit delivers more energy yearly than a 1,000 MW wind farm..