Hawaii Gas is seeking to increase a typical Oahu customer’s bills by nearly 20 percent.

The state’s only gas utility filed an application to increase rates statewide with the Public Utilities Commission on Tuesday.

If it is approved by the PUC, the typical household bill on Oahu will increase by $9.50, or 19.7 percent. The current typical bill on Oahu is $48 a month, according to Alan Tang, spokesman for Hawaii Gas. Tang said a typical residential customer has a stovetop or a dryer that requires gas. The utility also supplies gas to water heaters, pools, Jacuzzis and tiki torches.

Hawaii Gas said the rate increase would pay for “fuel diversification projects” and increased system reliability.

“We are committed to ensuring that our customers can count on us every day for the gas they need for cooking, drying, heating and lighting,” said Alicia Moy, president and CEO of Hawaii Gas, in a prepared statement. “Regular investments in operational infrastructure are essential to ensuring the safety and reliability of the gas products we manufacture and deliver.”

Hawaii Gas said the requested increase is not related to changes in fuel cost.

The gas utility has to hold public hearings about the rate change as part of the PUC review. The first hearing will likely be in November, Tang said.

Another part of the process includes a test year. Pending PUC approval, the utility will put its rate increase in place in 2018.

“We get results from the test year and then they can make a decision based on that,” Tang said.

Tuesday’s application was the first time Hawaii Gas has filed for a rate increase in nine years, the company said.

“We have worked hard over the past decade to manage costs, and we have been able to keep our request for a rate increase to a modest level,” Moy said.

PUC approval of the request would lead to an average 15 percent increase in rates statewide.

Monthly residential bills would increase by $14.50 on Maui and by about $4.55 on Molokai, and decrease by $4.15 on Lanai. Hawaii island and Kauai residential customers would not see any impact, on average.

The utility said pursuing local natural gas projects to reduce its dependence on imported oil also contributed to the need for a rate increase.

In 2016, Hawaii Gas put out a request for proposals to purchase raw biogas and bio-methane, a resource readily available from municipal wastewater treatment centers and landfills. The utility said it plans to blend the natural gas with the synthetic natural gas and liquefied natural gas it already uses.

Earlier this year, Hawaii Gas said it plans to integrate biogas from the Honouliuli Wastewater Treatment Plant into its pipeline, buying the plant’s leftover biogas.

Hawaii Gas serves nearly 28,000 residential, commercial and industrial customers on Oahu. The company distributes synthetic natural gas to those customers through approximately 1,000 miles of pipeline.

Only regulated customers will see a change in bills if the PUC approves Hawaii Gas’ application. Those customers primarily consist of homes and businesses connected to Hawaii Gas pipelines.

Tang said the rate change won’t affect customers who have a tank on their property.