Hawaii has become the fifth U.S. state to adopt a Clean Fuel Standard (CFS), a move expected to increase demand for biodiesel, renewable diesel and sustainable aviation fuel (SAF) while cutting the carbon intensity of transportation fuels by at least 50% by 2045.
Governor Josh Green signed the legislation on July 14, requiring the Hawaii Department of Transportation (DOT) to establish rules for the programme by Jan. 1, 2028, and begin implementation by Jan. 1, 2029, Biomass Magazine reported.
The law mandates a phased reduction in the carbon intensity (CI) of transportation fuels, with a target of at least 10% below 2019 levels by 2035 and 50% below 2019 levels by 2045. The DOT will set annual carbon intensity standards to achieve these goals.
Hawaii joins California, Oregon, Washington and New Mexico, which have already implemented similar clean fuel programmes designed to lower greenhouse gas emissions from the transportation sector.
The Clean Fuel Standard will operate as a credit-based system, allowing fuels with carbon intensity below the annual benchmark to generate credits, while higher-carbon fuels will incur deficits. The programme is technology-neutral and uses the U.S. Department of Energy’s GREET lifecycle emissions model to determine fuel carbon intensity.
Gasoline, diesel and other fuels used by aircraft, railroad locomotives, military vehicles and interstate waterborne vessels will be exempt from the programme. However, these sectors will have the option to participate voluntarily and generate credits by using low-carbon alternative fuels.
The legislation also includes provisions aimed at protecting consumers from unreasonable fuel price increases resulting from the programme.
Industry group Clean Fuels Alliance America welcomed the measure, saying it would create new market opportunities for biodiesel, renewable diesel and sustainable aviation fuel.
Governor Green said the Clean Fuel Standard would support Hawaii’s transition to a cleaner and more resilient economy by encouraging sustainable transportation fuels without mandating any single technology. Industry representatives added that wider use of low-carbon fuels would help the state achieve its climate objectives while delivering cleaner air and public health benefits.
