Hawai'i residents are on track to cut their energy use this year for the first time in eight years.

Hawaiian Electric Co., which provides most of the state's power, said yesterday that higher prices have convinced many residents to reduce electricity consumption.

On O'ahu, the average residential customer likely will pay 16 percent more for electricity this month compared with last August. Consumers are responding by turning off air conditioners, pool heaters, stoves, lights, fans and other switches.

"We expect this to continue as fuel prices remain high," T. Michael May, Hawaiian Electric president and chief executive officer, said in a conference call yesterday with analysts and investors.

Hawaiian Electric sold 4.85 billion kilowatt hours of electricity through the first six months of the year. That's 0.3 percent lower than a year earlier and came as the utility took on more residential customers.

Hawaiian Electric had previously forecast consumption to increase 3.4 percent this year, but now says it expects usage to decline.

If the projection holds, it will be the first time in eight years that the state's largest utility has sold less electricity than the preceding year.

Electricity bills have been rising because of higher costs for the fuel oil burned in generators. Hawaiian Electric's costs for a barrel of fuel increased 35 percent on average during the first six months of this year.

Hawaiian Electric passes on rising fuel costs to consumers in the form of an "energy cost adjustment," which is added to monthly bills.

The state also granted Hawaiian Electric an interim rate hike in September.

Hawai'i consumers pay the highest utility rates in the nation, according to the U.S. Energy Information Administration.

Reach Greg Wiles at gwiles@honoluluadvertiser.com.