Sempra 620-MW plant in Mexico off-line

LOS ANGELES, Aug 12 (Reuters) - Sempra Energy's (SRE.N) 620-megawatt Termoelectrica de Mexicali natural gas-fired power station in Mexico was off-line by Tuesday afternoon, a report by the California grid operator showed.

The unit was fully shut on Tuesday after having only 10 megawatts out of service on Monday, according to reports by the California Independent System Operator.

The plant near Mexicali, Baja California, has a combined-cycle power unit that opened in 2003. It is about 115 miles east of San Diego, and supplies power to the U.S. market.

One megawatt powers about 650 homes in Southern California.

Sempra Generation, a subsidiary of the San Diego-based company, owns and operates the station. (Reporting by Bernie Woodall; Editing by Braden Reddall)