Total U.S. nuclear plant availability dipped early June 9 to 90.89%, down from 91.55% on June 8 and also holding below the 95.11% reported on the same day in 2016.
Pulling down total output was the unexpected loss of Riverstone Holdings LLC's Susquehanna 1 in Pennsylvania. According to a report filed with the U.S. Nuclear Regulatory Commission, the unit was automatically scrammed late June 8 "due to a loss of Main Turbine Electro-Hydraulic Control (EHC) logic power causing a High Flux Reactor Power RPS [Reactor Protection System] trip." Prior to the incident, the plant was pegged at 100% power.
Offsetting the outage was the return of Exelon Corp.'s LaSalle 2 in Illinois. The reactor was warming up at 12% early June 9 after being taken offline June 7 for undisclosed reasons.
In addition, Southern Co.'s Vogtle 1 in Georgia returned to full power early June 9, rising from 80% on June 8. Tennessee Valley Authority's Sequoyah 2 in Tennessee was operating at 96% power early June 9, increasing from 75% the day prior.