Alternative Fuels/Technologies


Biofuels are a renewable energy source that can be stored and transported in a manner similar to fossil fuels. They can often be used in existing equipment and be blended with petroleum fuels. Biofuels categorically covers a variety of substances including biodiesel, ethanol, and biogas, among others.


In Hawaii, biodiesel is produced locally by Pacific Biodiesel  on Maui and Hawaii Island, and is available across the state. Biodiesel’s physical properties are similar to those of petroleum diesel but it is a cleaner-burning alternative that can result in a 75.8% reduction in carbon dioxide emissions. It is non-toxic and biodegradable.

In Hawaii, biodiesel is produced locally by Pacific Biodiesel on Maui and Hawaii Island. Pacific Biodiesel’s Hawaii Island refinery utilizes state-of-the-art distillation technology to produce the nation’s highest quality biodiesel and was the first facility in the world to be certified by the Sustainable Biodiesel Alliance for its sustainable production and distribution practices.

Many fleets in Hawaii have integrated 20% biodiesel into their diesel blends, and some also operate vehicles on 100% biodiesel.


Ethanol is a common component of today’s gasoline. Over 40% of the gasoline in the United States contains ethanol and the percentage is projected to increase. Ethanol is an alcohol-based fuel produced from plant sugars such as corn and sugarcane or from cellulosic feedstocks (grass, wood, crop residues, or old newspapers). Ethanol is used to reduce carbon dioxide emissions from gasoline.


Biogas, also known as renewable natural gas (RNG) or biomethane, is natural gas or methane produced from organic materials such as wastewater treatment plants, landfills, or agricultural crops, by anaerobic digestion. Because biogas is chemically identical to the fossil-fuel derived natural gas, it can be used in existing natural gas distribution systems and must be compressed or liquified for use in vehicles.

Locally, Hawaii Gas opened the first renewable wastewater biogas facility in late 2018 at the Honouliuli Wastewater Treatment Plant in Ewa Beach.

Electric Vehicles (EV)

Plug-in electric vehicles use rechargeable onboard batteries to store from the electrical grid or rooftop solar to power one or more on-board electric motors. Plug-in hybrid vehicles can use both the onboard battery as well as a gasoline backup, while full battery electric vehicles only have the battery and no gasoline backup. These battery electric vehicles produce no tailpipe emissions but do have upstream emissions associated with the production of electricity.

However, even with the electric grid as it is today, EVs are still more environmentally friendly to fuel than their gas-powered counterparts. Under Hawaii’s average 2019 electricity grid mix, an EV operating in the state released only 37% of the per-mile emissions of an average 22mpg gas car. On islands with more renewable integration, that number is even lower.

The price of EVs has come down over the past few years as battery costs have come down. With fuel and maintenance cost savings EVs can save residents money over the lifecycle of the vehicle. EVs are even expected to start reaching up-front cost parity with gas car equivalents around 2024.

Many people can conveniently charge their electric vehicles at home, by plugging it in overnight and topping off the battery. However, those living in multi-unit dwellings like apartments or condominiums may need to rely more heavily on the public charging network.

EVs in Hawaii

A key component of reducing fuel demand and utilizing locally produced renewable energy as Hawaii moves toward its 100% Renewable Portfolio Standard will be a vibrant plug-in electric vehicle (EV) market. All four Hawaii Mayors set goals of 100% renewable ground transportation by 2045, and to reach that goal will require strong investment in EV charging infrastructure and strong incentives for EV owners in early stages of adoption.


EV buyers can access a $7,500 federal tax credit for any full battery-electric vehicle, to be used as a credit on next year’s taxes. Plug-in hybrid electric vehicles are eligible for $2,500 for the first 5 kilowatt-hour of battery capacity plus $417 for each additional kilowatt-hour. 

This credit is available for each vehicle manufacturer until they sell 200,000 electric vehicles. General Motors and Tesla have already reached this limit and are therefore no longer eligible for the tax credit.

EV Charging

The U.S. Department of Energy’s Alternative Fuels Data Center  hosts an up-to-date database of EV chargers and, as of publication, indicates that there are 285 publicly available Level 2 and DC Fast Charging stations with 670 charging outlets across the state of Hawaii. Locations can be accessed through a variety of EV charging phone apps including PlugShare, Chargeway , and other company-specific sites. Hawaiian Electric also operates a public DC Fast Charging network  across their areas of service. Find a charging station near you. 

EV Organizations & Resources

Many local resources exist for those interested in EVs or current EV owners. Drive Electric Hawaii is a local hub of public and private members that are committed to educating the public about electric vehicles; Big Island EV Association and Kauai EV are community groups where EV owners connect and share; and Hawaii Electric Vehicle Association fosters collaboration among EV clubs EV owners across the islands.

Hydrogen and Fuel Cells

As the simplest and most abundant element in the universe, hydrogen can be used as a fuel for internal combustion engines (ICEs) or fuel cell electric vehicles (FCEVs). Fuel cells convert hydrogen into electricity through an electrochemical process and are generally twice as efficient as a combustion engine. Fuel cells produce zero emissions and have a similar range and refuel times as gasoline powered vehicles.

The first publicly available hydrogen refueling station and hydrogen electric vehicles have come on the market in Hawaii with the 2018 launch of Servco Toyota’s Mapunapuna Hydrogen Refueling Station  and the Toyota Mirai. The Mirai is available for lease through Servco Toyota and comes with free fuel during that leasing period.

The Hawaii Center for Advanced Transportation Technologies (HCATT) runs numerous hydrogen demonstration projects including a fuel cell hybrid step van, fuel cell hybrid aircraft tow vehicle, and fuel cell powered light cart, among others. HCATT is a federally funded project administered by the Hawaii Technology Development Corporation (HTDC).

Hawaii Natural Energy Institute, an organized research unit of the School of Ocean Earth Science and Technology of the University of Hawaii at Manoa, performs research, conducts testing and evaluation, and manages public-private partnerships across a broad range of renewable technologies to reduce Hawaii’s dependence on fossil fuel. Some of those research projects involve fuel cell and hydrogen technologies.