Sandy knocks out 90 NY state power lines, 13 pct of generation

HOUSTON, Oct 30 (Reuters) - New York's electric grid operator said more than 90 transmission lines remained out of service on Tuesday afternoon, a day after Hurricane Sandy slammed into the East Coast with 80 mph winds and record storm surge.

Despite damage to the power grid and the loss of about 13 percent of in-state generation from high wind and flooding, the New York Independent System Operator (ISO) said the bulk electric system was in compliance with industry transmission and operating reserve requirements on Tuesday.

More than 7.3 million homes and businesses along the U.S. East Coast were still without power Tuesday afternoon as the remnants of Hurricane Sandy moved across Pennsylvania.

The ISO said 90 transmission lines were out in southeastern New York. Utilities are beginning to assess infrastructure damage, but some substations are not yet accessible due to high water.

The 5,300 megawatts of generation represents 13 percent of New York's in-state generating capacity of 39,570 MW, the ISO said.

Demand early Tuesday was about 4,400 MW lower than it was at the same time Monday in advance of Sandy's making landfall. Monday's statewide load was 16,830 MW.

Tuesday's peak demand was expected to be 15,000 MW, the ISO said, down from an average peak load of about 20,000 MW experienced on a normal day in late October.

One megawatt serves about 800 to 1000 homes in New York, the ISO said.

(Reporting by Eileen O'Grady in Houston; Editing by David Gregorio)