SAN CLEMENTE - Southern California's only big nuclear reactor complex remains throttled down to just 25 percent of its power capacity, as its owner saves fuel to meet power demands next summer, it was reported today.

The San Onofre Nuclear Generating Station, on the San Diego-Orange county line, has one nuclear reactor working at half capacity, and the other shut off completely, the San Diego Union-Tribune reported.

The plant's Unit 3 will remain at half capacity for about 45 days and will be brought up to full power output when demand requires it this summer, said Gil Alexander, a spokesman for plant operator Southern California Edison, to the newspaper.

San Onofre's Unit 2 remains in shutdown mode following replacement of its central steam generators last fall. Alexander told the newspaper that its restart has been delayed due to problems with the generator replacement, which involved Advertisement

[ Berry-Bell and Hall Mortuary ] cutting in to the massive radiation containment dome visible next to Interstate 5 at the north end of Camp Pendleton.

The utility will not say when Unit 2 will be restated for proprietary reasons, Alexander told the Union-Tribune. The plant's Unit 1 was declared obsolete and removed long ago.

At full capacity, the nuclear station can generate 2.2 billion watts of electricity, enough to supply 1.5 million residences. Edison owns 78 percent of it, San Diego Gas & Electric Co. owns 20 percent of it, and the City of Riverside owns 2 percent of it.

Earlier this month, the federal Nuclear Regulatory Commission issued two reports criticizing the nuclear plant operators for failing to maintain an atmosphere of safety an non-retaliation for its workers, and for failing to draw up an acceptable plan to avoid a repeat of backup battery problems first noticed two years ago.