Oahu residents saw a dime shaved off their electricity bills in July primarily due to lower fees collected for energy efficiency programs.

Hawaiian Electric Co.’s bill for an Oahu household using 500 kilowatt-hours was $141.79, or 26.3 cents a kilowatt-hour, compared with $141.89, or 26.3 cents a kilowatt-hour, in June.

HECO spokeswoman Shannon Tangonan said revised Public Benefits Fund (PBF) surcharges and Green Infrastructure fees had an impact on customers’ bills.

Those line items included in the HECO bill calculation don’t go to the utility.

The PBF surcharges go to an energy efficiency program called Hawaii Energy. The Green Infrastructure fees are distributed to a renewable-energy loan program called Green Energy Market Securitization, or GEMS. On July 1 the Green Infrastructure fee went down to $1.18 from $1.27. The fee is adjusted every six months.

On Oahu half of the energy HECO uses is bought from eight independent power producers, which include AES Hawaii, a coal-fired facility in Kapolei and the Kahuku Wind facility on the North Shore.

The cost of electricity in the state is more than double the national average, as Hawaii residents paid an average of 30.33 cents a kilowatt-hour for electricity in April. The national average was 12.70 cents in the same month, according to the latest figures from the U.S. Energy Information Administration.

The higher cost of electricity in Hawaii is widely attributed to the state’s use of fossil fuels. In 2015 HECO’s energy mix was roughly 71.1 percent oil on Oahu. HECO imports oil primarily from Southeast Asia and the Middle East.

Neighbor island residents saw bills dip in July.

The residential cost for Hawaii Electric Light Co. customers on Hawaii island dropped about $10. Hawaii island’s July electrical bill is $158.79, or 29.4 cents a kilowatt-hour, down from $168.82, or 31.4 cents a kilowatt-hour, in June.

“Hawaii island typical residential bills saw a hefty dip due to lower fuel and purchased power costs, as well as the impact of PBF and Green Infrastructure fees,” Tangonan said.

Maui Electric Co. customers saw bills decrease $3.10.

The average bill for a Maui household using 500 kilowatt-hours was $156.51, or 29.4 cents a kilowatt-hour, compared with $159.61, or 30 cents a kilowatt-hour, in June.

Tangonan said typical residential bills went down on Maui because the electrical utility didn’t have to buy as much wind power and had lower fuel costs, as well as due to the impact of PBF and Green Infrastructure fees.

Customers on Molokai and Lanai also saw lower bills in July compared with June.

MECO customers on Molokai using 400 kilowatt-hours of electricity are paying an average of $138.83, or 32.3 cents a kilowatt-hour. In June utility customers paid $139.44, or 32.4 cents a kilowatt-­hour.

Lanai residents using 400 kilowatt-hours of electricity are paying $142.28, or 33.2 cents a kilowatt-hour. In June residents paid $143.14, or 33.3 cents a kilowatt-hour.

Bills on Lanai and Molokai are calculated based on a typical household using 400 kilowatt-hours of electricity in a month. This is due to lower energy use compared with Maui, Hawaii island and Oahu, HECO said.

HECO, MECO and HELCO monthly bills include the cost for kilowatt-­hours used, plus other charges.

The Kauai Island Utility Cooperative’s rate fell to 31.20 cents a kilowatt-hour in July. In June the rate was 31.42 cents a kilowatt-hour. The typical bill for a household using 500 kilowatt-­hours in July is $166.61, including a $10.58 customer base charge. In June the bill was $167.70.