Residential electricity rates edged higher on Oahu in October, reversing three consecutive months of declining bills.

HECO officials said a typical 600-kilowatt-hour bill for Oahu residential customers rose by 55 cents to $210.37 in October from $209.82 in September. The effective rate for electricity on Oahu is 33.6 cents a kilowatt-hour, up from 33.5 cents a kilowatt-hour last month. Electric rates had fallen from July through September.

Elsewhere in the state:

» Maui Electric Co. customers saw rates rise to 36.10 cents per kilowatt-hour this month from 34.9 cents in September. The typical Maui bill rose by $7.56 to $225.68.

» Hawaii island residential rates fell to 40.4 cents a kilowatt-hour from last month’s 40.7 cents. The typical bill fell by $2.06 to $252.63.

» On Kauai the rate rose to 44.9 cents per kilowatt-hour from 43.1 cents per kilowatt-hour in September, according to the Kauai Island Utility Cooperative.

HECO and KIUC adjust their rates monthly largely to reflect changes in fuel costs. The utilities generate about 80 percent of their electricity from petroleum, making rates sensitive to swings in oil prices.

On Kauai, where electric rates are the highest of the four major islands, the utility is moving forward with a plan that would cut bills to generate power by burning wood chips instead of oil.

A developer hired by KIUC finalized financing this week for a power plant that would burn wood chips from locally grown trees. The facility, which would satisfy 11 percent of the island’s electricity demand, would save ratepayers anywhere from $70 to $190 a year on their electric bills, according to the state Office of the Consumer Advocate.

Hawaii has the highest electrical rates in the nation. The statewide average of 37.7 cents a kilowatt-hour in July was more than triple the national average of 12 cents a kilowatt-hour, according to the most recent numbers available from the U.S. Energy Information Administration. Louisiana had the lowest average rate at 8.5 cents a kilowatt-hour.