"The crisis with the power plants and the unexpected unscheduled outages is over," said Jose Dizon, a HECO spokesman. "But with the hot weather we are still asking customers to conserve. And it is the right thing to do."

HECO had asked the 150 biggest power users on O'ahu yesterday to conserve electricity until 9 p.m., and appealed to everyone to cut back after two sweltering days of record electricity use.

Record demands for power have been set four times since Aug. 17 and reached a high mark of 1,327 megawatts Tuesday night. Monday night had seen a record, too: 1,319 megawatts.

As HECO engineers and managers monitored usage yesterday, some of their fears were eased by late afternoon when two of the troubled generators — one owned by HECO and the other by Kalaeloa Partners — were back in use, Dizon said.

Pearl Harbor Naval Station also supplied HECO with additional standby power.

"At 7 o'clock our peak was about 1,278 megawats," Dizon said. "That was a big sigh right there when we hit that and it was that low."

The third troubled generator, which is owned by HECO, remains out of service and it is not known when it will be back in use, Dizon said.

The other out-of-service generators — a HECO generator and the city's H-Power unit — remain offline.

HECO has 16 generators, and would like to add another one by 2009 at Campbell Industrial Park, Dizon said.

HECO said its customers responded to the plea for help, reducing the amount used by 49 megawatts.

"It is likely a large portion, though not all, of that savings

is due to individuals and businesses doing the right thing, and we are grateful," said Chuck Freedman, HECO vice president of corporate relations.

Freedman praised the efforts of Pearl Harbor Naval Station, as well as so-called interruptible-load customers, who pay a reduced rate with the understanding that HECO can shut off their power in an emergency.

"Our military friends at Pearl Harbor and our interruptible-load customers have really come through for us," Freedman said. "...Other large customers have been cooperative as well,"

Manoa Valley resident David McCauley and his neighbors lost power Tuesday night for more than two hours and then again last night for about 30 minutes.

"I was mad because it happened just when the presidential debate was on," McCauley said last night. "Then the power finally came back on."

HECO asked customers yesterday to reduce their use of appliances such as clothes dryers, dishwashers and air conditioners through the evening hours.

Large customers, such as hotels and military installations, also were asked to cut back by turning off lights, raising the thermostat on air conditioners and shutting doors.

University of Hawai'i officials, whose six O'ahu campuses collectively make UH one of the top three energy users on O'ahu, got HECO's e-mailed appeal yesterday, and checked for unusually high energy use but found none.

"With night classes, we're basically a 6 a.m. to 9 p.m. operation," UH spokesman Jim Manke said last night. "So it's tough. Night classes need to have the lights on and the air on if they're closed buildings. We also have a built-in problem where some buildings simply need to keep

the air conditioning on for projects that have to be temperature controlled."

In an unrelated energy problem, a leaking power transformer at the Manoa campus' Hale Wainani student residence left 650 UH students without power overnight. Power was restored at about 4:30 a.m. today.

Earlier in the day, HECO said that if it lost another generator or if demand were too great, it would have to shut down power to "blocks of customers" to maintain the stability of the power system. The procedure, "load shedding," is designed to ensure that hospitals and key public safety organizations continue to have electricity.

Some hospitals, such as The Queen's Medical Center, said yesterday they have emergency backup generators to keep running during power failures.

Rolling blackouts are more common on the Big Island. At the beginning of the year, officials there triggered a blackout, leaving 1,800 customers without power, after an equipment failure halved power production at a plant in Hamakua. It marked the first rolling blackouts on the Big Island since 2002.

O'ahu's major blackouts — in 1983, 1988 and 1991 — happened because of transmission problems, not generator problems.

If blackouts are necessary, Dizon said, HECO will warn the public through the media, and the blackouts will not last more than two hours.

Temperatures yesterday hit the upper 80s, but it felt much hotter because of high humidity, weather forecasters said. More of the same is expected today, although things could cool off by tomorrow.

Reach Dan Nakaso at dnakaso@honoluluadvertiser.com or 525-8085. Reach Mike Gordon at mgordon@honoluluadvertiser.com or 525-8012.

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