Spain's Cofrentes nuclear plant in power drop

MADRID, July 13 (Reuters) - Spain's 1,000 MW Cofrentes nuclear plant had to cut power early on Sunday due to technical problems -- for the second time in three days -- the nuclear watchdog said.

The Nuclear Safety Council (CSN) said power was cut to 70 percent of normal output at 0252 GMT to allow technicians to repair a feedwater pump.

Officials at the Iberdrola-owned (IBE.MC) power station near the eastern port of Valencia were not available for comment.

Output was cut to around 65 percent on Thursday night at Cofrentes in order to close a safety valve, after which technicians said they expected the plant to be back to full power early on Saturday.

Data from national grid operator REE (REE.MC) showed that Spain's nuclear power plants were providing 5,879 MW at 0820 GMT, compared to about 7,700 MW when all eight are working at full power.

This suggested that the 500 MW Santa Maria La Garona plant was still offline after halting for repairs on Thursday, in addition to the 1,000 MW Asco I plant, which was disconnected from the grid on June 10 for cleaning up after a controversial leak.

Prompt power prices <SP/BASE> tend to rise when nuclear power stations close, although they are also influenced by demand and the availability of wind power and hydroelectricity. (Reporting by Martin Roberts; Editing by Louise Heavens)