KALAELOA — Tesoro Hawaii workers were attempting to gradually restart the processing units at its Kalaeloa refinery yesterday after a power failure caused a fire at one of the units late Saturday night.

A Tesoro spokesman said the shutdown was not expected to affect the state's fuel supply. Tesoro is one of two refineries in Hawai'i. The other, owned by Chevron, also is in Kalaeloa's Campbell Industrial Park.

"We don't anticipate any supply issues, fortunately, so that's a good thing," said Nathan Hokama, Tesoro spokesman.

The company was still investigating what caused the 10 p.m. Saturday electrical failure. It took about an hour for Tesoro and Honolulu Fire Department personnel to put out the fire and cool the processor so the fuel inside would not reignite, Hokama said. What type of fuel was being produced at the unit that caught fire has not been disclosed.

There were no injuries or evacuations caused by the incident.

Power at the entire refinery was shut down until about 2 a.m. yesterday, Hokama said.

Yesterday afternoon, the company was gradually bringing the units back into service.

"Each unit has a different function, and there are about a dozen major units," Hokama said. Some help distill imported crude oil while other units further refine the oil into gasoline, diesel oil, jet fuel, bunker fuel for ships and fuel oil for electrical utilities.

About 95,000 barrels of crude oil are processed daily at the refinery, Hokama said.

"Based on what (Tesoro executives) were told, there shouldn't be an impact to the supply because they do have an inventory in the tank farm," he said.

The refinery is at 91-325 Komohana St. on the southeastern portion of Campbell Industrial Park.

The facility was built in 1972 and has been operated by PRI and BHP Petroleum. Tesoro took over the refinery, as well as retail gas stations and distribution facilities, in 1998.

Six HFD engine companies and the HFD hazardous materials unit responded to the alarm, fire Capt. Terry Seelig said.

A command post was set up, and HFD firefighters stood by as a precaution as Tesoro workers started to bring power back to the refinery.

Reach Gordon Y.K. Pang at gpang@honoluluadvertiser.com.