Renewable Natural Gas

Renewable Natural Gas

In 1948, Hawai‘i Gas opened its first plant laboratory with equipment to improve waste systems and remove tar from gas. Now called renewable natural gas (RNG), ultra-clean methane is produced from organic matter decomposition.

Hawai‘i Gas pioneered capturing biogas at the Honouliuli Wastewater Treatment Plant, generating 800,000 therms yearly, equivalent to fueling 6,000 homes. This project cuts oil demand by 15,000 barrels and slashes emissions equal to 400 cars yearly. Since 2018, the City and County of Honolulu earned $1.85 million from biogas sales that are blended in our mix and delivered in Hawai'i Gas pipelines.

Liquid natural gas tanks and silos

The Honouliuli RNG Facility, painted an eye-catching bright green, takes the gases that are a by-product of wastewater treatment and turns them into clean-burning biomethane.

The wastewater feedstock is upgraded through a multi-step process to create renewable natural gas in the form of biomethane.

Biogas upgrading to biomethane diagram.
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