Biodiesel

What Is Biodiesel?

How Is It Used?

Why Does It Matter?
Biodiesel is a 100% renewable fuel that can be used in any diesel engine, without modification. It’s “renewable” because it’s made from naturally occurring sources such as vegetable oil or animal fats. Pure biodiesel reduces harmful greenhouse gas emissions by 86% compared to petroleum diesel. Biodiesel is also safer to store and handle because it is non-toxic, biodegradable, eliminates risk from environmentally hazardous fossil fuel spills, and is rated non-flammable.
Biodiesel and vegetable oil are NOT the same thing. Biodiesel is produced through a simple chemical process called transesterification, which converts vegetable oils and fats of natural origin into fatty acid methyl esters through a reaction with a small amount of methanol followed by purification into a finished fuel. As an advanced biofuel, biodiesel must meet strict ASTM D 6751 quality parameters. In the video below, our team explains how Pacific Biodiesel® produces this 100% renewable fuel at our refinery on Hawaiʻi Island.
One of the great advantages of biodiesel is that it can be used in existing diesel engines and diesel vehicles, using existing liquid fuel infrastructure. Biodiesel can be pumped, stored and burned just like petroleum diesel fuel. Biodiesel contains no petroleum. It can be used in pure form or it can be blended at any level with petroleum diesel – a common blend is 20% biodiesel with 80% petroleum diesel, known as B20.
Fossil fuel is extracted once from the earth and releases harmful greenhouse gas emissions that have been damaging the environment for over a century. In contrast, our biodiesel is sustainably produced from natural sources like sunflower oil from our local agriculture operations and from used cooking oil and grease that we recycle from Hawai‘i’s restaurants and foodservice operations, keeping this waste out of our community landfills and water streams.
Biodiesel Benefits

Environmental
- Biodiesel reduces lifecycle greenhouse gas emissions by 86% compared to petroleum diesel.
- Biodiesel is biodegradable and non-toxic.
- The National Fire Protection Association classifies biodiesel as a non-flammable liquid (Class III-B).
- Biodiesel is safer to handle and store than petroleum diesel.
- Biodiesel eliminates risk from environmentally hazardous fossil fuel spills.
- Biodiesel is an ultra-low sulfur fuel with virtually zero aromatics. Emissions from sulfates, a major contributor to acid rain, are practically eliminated when using pure biodiesel.
- Research shows that biodiesel contributes to healthier air quality and creates significant community health benefits.

Economic
- Pacific Biodiesel’s community-based production model creates local jobs, helps diversify the state’s economy, and reduces reliance on imported fuel thereby enhancing Hawaiʻi’s energy security.
- Our company is a local business, producing and selling our fuel entirely in Hawaiʻi to keep economic and environmental benefits in the state’s economy.
- In the past, Hawaiʻi restaurants were paying up to $2 per gallon for proper removal and disposal of their used cooking oil; since 2010 Pacific Biodiesel has performed this service at no charge – we recycle these waste oils for use in our biodiesel production.
- A study commissioned by Clean Fuels Alliance America reports that 2024 U.S. biodiesel production exceeded 5 billion gallons, generated $42.4 billion in economic activity, and supported 107,400 jobs that paid $6 billion in annual wages.

Engine
- Fuel economy using biodiesel is practically identical to petroleum diesel fuel.
- Biodiesel is comparable to the efficiency, horsepower and torque of petroleum diesel fuel.
- Biodiesel has a higher cetane rating and improved lubricity, which may help prolong engine life. It also helps eliminate injector and fuel system deposits, which can extend maintenance intervals.
Biodiesel Production
Our Hawai‘i Island Refinery
As Hawai‘i’s only commercial producer of liquid biofuels for three decades, Pacific Biodiesel® produces 6 million gallons of premium, distilled biodiesel each year at our refinery on Hawaiʻi Island. Our biodiesel is sold entirely in Hawai‘i, supporting the State’s mandate to reach 100% renewable electricity production by 2045. Our annual production of biodiesel is equal to more than 220 MWh PER DAY of 100% renewable energy for Hawai’i.
We produce our biodiesel primarily from used cooking oil (UCO) and grease trap waste. The feedstock we most frequently process at our refinery includes used cooking oil, tallow and yellow grease. For every gallon of these waste oils we recycle, we’re able to produce nearly one gallon of biodiesel!
We also produce biodiesel with virgin vegetable oils from crops like sunflowers that we are regeneratively farming on Maui and Kauaʻi – supporting diversified agriculture and food security in our island state.
Pacific Biodiesel’s domestic production of 100% renewable fuel also plays an important role in supporting energy security in our island state. As part of the company’s multi-year agreement with the U.S. Army Corps of Engineers announced in 2024, for its Engineer Research and Development Center’s Construction Engineering Research Laboratory, we help ensure a reliable, readily available local supply of energy-dense biofuel that can be used in military installation power production and mobility in Hawaiʻi and the Indo-Pacific region to protect United States national security and military preparedness. Learn more in our project fact sheet.
Pacific Biodiesel is acutely aware of the important role our local biodiesel production plays as a domestic energy source to support our state’s energy resilience, military readiness and circular economy. We have developed a strategic 2040 Vision that outlines a realistic pathway for local biodiesel production to support Hawaiʻi’s mandate for 100% renewable electricity production by 2045.
- In the 2045 mix of renewables, 12% is estimated to be liquid renewable fuel - biodiesel - supporting other renewables like solar and wind.
- This will require an additional 10 million gallons of local biodiesel production each year, along with our current refinery’s annual production of 6 million gallons.
- By 2040, Pacific Biodieselʻs local agriculture operations will enable 100% locally sourced feedstock required to annually produce 16 million gallons of biodiesel for Hawaiʻi.
Pacific Biodiesel has designed and built more than a dozen biodiesel refineries around the world, advancing processing technology for each iteration. Today, Hawaiʻi remains our home – and 2025 marks our company’s 30th anniversary. The direct impact from Pacific Biodiesel’s 30 years of biodiesel production in Hawaiʻi includes:
- 70 million gallons of biodiesel have been produced for Hawaiʻi, from our initial small-scale plant on Maui to our world-class refinery today on Hawai‘i Island.
- We estimate that by using our 100 percent renewable fuel over the past three decades, our biodiesel customers have reduced greenhouse-gas (GHG) emissions by nearly 1.5 BILLION pounds of CO2.
- 17 million gallons of local UCO from Hawai‘i’s restaurants have been recycled by our company for use in the production of our biodiesel.
We’re proud of the advanced biodiesel process technology our pioneering team designed more than a decade ago. Here are some highlights about our world class refinery’s impressive, zero-waste production process:
- Pacific Biodiesel’s robust process chemistry and three-stage product refining allows us to use a multitude of feedstocks to produce our premium fuel that meets ASTM standards. Our multi-stage reaction efficiently converts fatty acids and glycerides to methyl esters, while our high-vacuum distillation and dry refining steps remove trace amounts of water, methanol and minor impurities to yield a fuel with exceptional quality and a long shelf life.
- Pacific Biodiesel’s unique reaction technologies allow us to recycle and use highly degraded feedstock – fats, oils and grease with up to 50% Free Fatty Acid (FFA) – without loss of yield. Our process is also designed to handle contaminants commonly found in used and unrefined oils and fats. These include moisture, insoluble and inorganic impurities, excess unsaponifiable matter and phospholipids.
- By employing precise reaction chemistry and proprietary ester and byproduct refining technologies, our process delivers the highest possible yield from any feedstock used. Our process is designed to recycle every drop of feedstock diverted in the production process and sized to ensure consistent output even through feedstock transitions.
- Our zero-waste operation includes process equipment that recovers all excess methanol. Careful attention is paid to creating conditions that maintain high product quality during evaporation and distillation. The use of our three-step recovery system keeps methanol consumption to the theoretical minimum while producing high quality co-products. Our proprietary by-product refining technology also allows the recovery of glycerin from the crude byproduct stream – the resulting glycerin is later sold as a beneficial agent for wastewater treatment plants among other uses. We also recycle excess methanol and feedstock residues back into the production process, improving yield and lowering operating costs.
- A small environmental footprint is an essential aspect of a sustainable biodiesel facility. Our process includes vapor recovery to eliminate fugitive emissions and our dry refining process creates a non-hazardous solid from product impurities. Methanol recovery from all process streams keeps methanol consumption to a minimum and helps prevent the release of methane, a greenhouse gas. Strict safety procedures include continual monitoring to detect and rapidly resolve any methane leaks from the facility.
- Biodiesel quality is governed by ASTM International Standards. Each lot of biodiesel we produce is rigorously tested throughout the production process to ensure the fuel meets or exceeds the ASTM premium 1-B.
Customers
For power generation customers, our biodiesel is a reliable firm renewable liquid fuel to back up other renewables in Hawai’i’s electricity grid.
On-road, especially when used in today’s advanced diesel engine technology, our biodiesel produced from recycled used cooking oil is by far the lowest lifecycle greenhouse gas transportation fuel available in Hawaiʻi.
Browse these examples of how our 100% renewable fuel is used by our customers around Hawaiʻi:
City & County of Honolulu
For more than 15 years, the City & County of Honolulu has used locally produced biodiesel in its fleet of vehicles, including nearly 1,000 pickup trucks, dump trucks, ambulances and garbage trucks.
“Changing our fuel source from ULSD to B20 was not a difficult decision considering the benefits of reduced emissions (PM, smoke and odor), local production and lower State and County (Oahu) taxes. No special dispensing equipment or modifications were necessary, and we have used B20 interchangeably with straight ULSD without issues. Use of B20 has increased our awareness about the importance of having clean and properly maintained fuel storage and dispensing systems.”
– Robert Primiano, Division Chief– Automotive Equipment Service, City and County of Honolulu
Department of Land and Natural Resources
“Biodiesel fits with DLNR’s mission. We’re doing so much work to protect our natural resources,” said DLNR Chair Suzanne Case. “Climate change is the biggest threat globally to our natural resources. We have to do everything possible to get off of fossil fuel, every single one of us. Biodiesel is non-toxic so it’s good for the engines and it’s good for our reef and our fishes.”
– Suzanne Case, formerly Chairperson of the State of Hawaii’s Department of Land and Natural Resources
Fair Wind Cruises
Fair Wind Cruises has been using biodiesel since 2013. “We converted all our vessels and company trucks to use locally produced biodiesel from Pacific Biodiesel, reducing our dependence on importing foreign fuel. Not only does biodiesel burn cleaner and is, therefore better for the ocean, it is better for our vessels and reduces our maintenance costs.”
– Alex Dant, Fair Wind Cruises
Polynesian Voyaging Society
“As Hōkūleʻa’s escort vessel, Hikianalia requires adequate power to meet our safety requirements at sea. We feel fortunate to have Pacific Biodiesel here in Hawaiʻi to provide a renewable fuel alternative for our canoe that is clean and safe for our oceans.”
– Nainoa Thompson, CEO of Polynesian Voyaging Society
Magic Island Construction
“All of our equipment has run just fine; we’ve had no problems,” Rindlisbacher reported. “Our team is very happy with the performance. And, believe me, I’d would hear if they had any issues”
– Lynn Rindlisbacher, owner of Maui-based Magic Island Construction
Kauai Island Utility Cooperative (KIUC)
“Biodiesel is very important for KIUC’s ability to reach its 100% renewable energy goals because it can be used in any of our existing generating units, and it can be stored in large tanks to give us that long duration storage that we need that batteries and current storage technology can’t provide. We need a fuel like biodiesel to get us through those periods where we have lots of clouds or rainy weather here on Kauai and we’re not getting the output from our solar farms. KIUC is very pleased to partner with Pacific Biodiesel, a Hawaii-based company that’s producing local biofuel, providing lots of clean energy jobs for people in the state, and helping us meet our sustainable electricity goals.”
– David Bissell, KIUC President and Chief Executive Officer
Maui Brewing Co.
“The number one reason for us using biodiesel was to lead by example in sustainable manufacturing. We can show that you can truly make an authentic local Hawaiian craft beer in Hawaii and do it with sustainable practices. Having a locally made fuel source gives us that energy independence but also something that to us is a value-added agricultural resource that we can use here and help to promote that our biodiesel came from Maui and is made from expended restaurant cooking oil or other sustainably grown ag resources like sunflowers.”
– Garrett Morrero, CEO and Founder, Maui Brewing Co.
Where To Buy Biodiesel And What To Expect
Ready to fuel up? Below are biodiesel locations around the state and helpful resources as you get started.
Below are locations around Hawaiʻi where you can purchase biodiesel.
To access any of the Pacific Biodiesel Fueling Stations*, download our free App from the “How to Access Our Fueling Stations” tab at left. To set up a commercial fuel account or to complete a tax exemption form to purchase off-road fuel, please contact Pacific Biodiesel Sales Manager Christopher Long at 808.283.1855.
Hawaiʻi Island
* Pacific Biodiesel Fueling Station - Keaʻau
B-99.9 Off-road and On-road fuel available
16-240 Mikahala Street, Keaau, HI 96749
808-877-3144
Station hours: Monday – Friday 8:00 am to 4:30 pm
* Pacific Biodiesel Fueling Station - Honokohau Small Boat Harbor
B-99.9 Off-road and On-road fuel available
74-429 Kealakehe Pkwy, Kailua-Kona, HI 96740
Located on the South Side of Honokohau Marina and Small Boat Harbor across the street from the restrooms.
Station hours: Open 24/7
HFN (B-99.9 & B-20)
On the corner of Kipimana St. and Wiliama St., Shipman Business Park, Keaau, HI 96749
Open 24 hours
Membership only station
Kauaʻi
* Pacific Biodiesel Fueling Station - Kaumakani
B-99.9 Off-road and On-road fuel available
812550 Kaumualii Hwy, Kaumakani, HI 96747
Station hours: Open 24/7
Maui
* Pacific Biodiesel Fueling Station - Kahului
B-99.9 Off-road and On-road fuel available
194 Lauo Loop, Kahului, 96732
Station hours: Open 24/7
* Pacific Biodiesel Fueling Station - Maʻalaea Small Boat Harbor
B-99.9 Off-road and On-road fuel available
101 Ma‘alaea Boat Harbor Road, Wailuku, 96793
Located on the pier near the Division of Boating and Ocean Recreation Office
Station hours: Open 24/7
Minit Stop Lahaina – Ohana Fuels (B-99.9 and B-20)
10 Kupuohi St., Lahaina, Hawaii
(808) 667-0737
O‘ahu
* Pacific Biodiesel Fueling Station - Sand Island
B-99.9 Off-road and On-road fuel available
1098 Sand Island Parkway, Honolulu, 96819
Station hours - Monday-Friday 7am-3pm
Carl’s Jr. 76 Station (B-20)
2140 N. Nimitz Hwy, Honolulu
(808) 848-0480
Union 76 Station (B-20)
565 Halemaumau St., Niu Valley
(808) 373-7112
Union 76 Station (B-20)
1206 S. King St., Honolulu
(808) 597-1130
Kaneohe Bay 76 (B-20)
46-047 Kamehameha Highway, Kaneohe
(808) 235-5254
Burt’s Union Service (B-20)
1342 North School Street, Honolulu
(808) 841-6711
* To access our Pacific Biodiesel Fueling Stations around the state, download our free App and learn more on the “How to Access Our Fueling Stations” tab at left.
Maui
Maui Oil Company
16 Hobron Ave
Kahului, HI 96732
(808) 871-6220
Maui Petroleum/Hawaii Fueling Network
385 Hukilike Street Suite #101
Kahului, Hawaii 96732
Sales & HFN Inquiries:
Tel: (808) 270-2802
O‘ahu
Aloha Petroleum
(808) 522-9222 Oahu
(800) 621-4654 Neighbor Islands
Customer Service is available from 8:00am to 4:30pm Monday through Friday
Par Hawaii
91-325 Komohana Street
Kapolei, HI 96707
Hawaii Island
Big Island Energy Company
50 Kukila Street
Hilo, HI 96720-4576
Toll Free: (866) 913-5501
Local: (808) 882-1002
Hawaii Petroleum/Hawaii Fueling Network
16 Railroad Avenue, #202
Hilo, Hawaii 96720
Sales & HFN Inquiries:
Tel Hilo: (808) 935-6641
Tel Kona: (808) 329-1862

Our off-grid biodiesel fueling stations around Hawaiʻi give you convenient 24/7 access to purchase biodiesel. Each station offers our premium distilled biodiesel for on-road, marine and other off-road use.
To purchase fuel from these biodiesel stations:
- First download the free app on your smart phone or mobile device . The app allows paperless fuel purchases, access to company news and informational videos. Download it from Apple’s App Store or Google Play.
- Then, follow the simple instructions on the graphic below; for your convenience, this graphic is also posted on the fueling station.
- To open a commercial account or to complete an M-38 tax exemption form to purchase fuel for marine or other off-road use, customers must first contact Pacific Biodiesel’s sales manager at 808.283.1855.
In the race to reduce greenhouse gas emissions in on-road transportation, biodiesel gives truckers the choice to use their existing diesel vehicle fueled with clean renewable fuel.
Diesel-engine trucks, preferred by America’s trucking industry, allows for a longer driving range and more drive time per shift compared to EVs that require frequent recharging and have a limited range per charge. Diesel vehicles can transport more payload compared to electric trucks that have reduced payload capacity due to heavy battery weight.
Below are helpful resources to review as you evaluate biodiesel to help green your fleet:
Biobased Diesel Daily
Clean Fuels Alliance America
Biodiesel Magazine
FAQs
Do I need to modify my diesel vehicle to use biodiesel?
No. All diesel engines and vehicles can use biodiesel or biodiesel blends. One of the major advantages of using biodiesel is the fact that it can be used in existing diesel engines without negative impacts to operating performance. Certain older vehicles built before 1993 may require replacement of fuel lines which contain natural rubber, as biodiesel can cause these lines to swell or crack. It is also important to note that newer diesel vehicle models of Volkswagen, BMW and Mercedes (2007 or later) have a Bosch designed fuel system that utilizes a late-post-injection system to regenerate the Diesel Particulate Filter (DPF) that can create a fuel/oil dilution in the diesel engine, whether petroleum diesel or biodiesel fuel is used. Over time the engine oil could be diluted by the fuel if certain precautions are not taken. If you use 100% biodiesel in these vehicles, you must change the oil at least every 3,000 miles and check your oil level regularly (this is not an issue with vehicles using biodiesel blends, such as B20). Any engine (Cummins, Ford, Isuzu, etc) using a proper in-exhaust injector to regenerate the DPF is unaffected by biodiesel.
Will using biodiesel void my warranty?
Can I store biodiesel?
Can I go back and forth between petroleum diesel and biodiesel?
Will I need to change my fuel filters more often when using biodiesel?
Can’t I just use vegetable oil like truckers did in the 1970s?
- Biodiesel is produced from naturally occurring fats and oils using transesterification.
- Biodiesel must meet the ASTM standard D6751 “Specification for Biodiesel (B100).”
Will using biodiesel lower my engine’s power and fuel efficiency?
Isn’t “zero emission” better than biofuels?
What do I need to know about using biodiesel in my boat?
- Ensure your fuel hoses are made with biodiesel compatible materials. DO NOT use natural rubber, butyl rubber or various nitrile rubber materials as these may degrade when used with 100% biodiesel, which is a solvent. DO use compatible elastomers such as Viton, PVC-Nitrile, Flouro-elastomers, Teflon, Silicon or Nylon. There are a wide variety of compatible hose types available for 100% biodiesel that are US Coast Guard certified. Contact us if you have any questions.
- Microbial activity has always been an issue with petroleum diesel fuel. High moisture content in the fuel can lead to microbial growth in fuel tanks that can lower horsepower output and may result in engine damage. In contrast, Pacific Biodiesel produces premium distilled biodiesel which is extraordinarily clean and dry. To avoid maintenance issues, ensure your fuel is always stored properly without exposure to moisture. Microbial activity can be temporarily treated with biocides (used sparingly); but it is important to fix any water leaks to avoid exposing the fuel to water.
History

With his diesel engine invention in the 1890s, Rudolph Diesel pioneered an innovative engine technology and the recognition of plant oils as a renewable fuel source. A century later, it was another pioneer, one right here in Hawaiʻi, that helped launch the modern biodiesel industry. That pioneer is Pacific Biodiesel Founder Bob King.
Hereʻs a look back at how the diesel engine – and biodiesel – made their impact on the world.
The diesel engine is invented. The diesel engine works on the principle of compression ignition, in which fuel is injected into the engine’s cylinder after air has been compressed to a high pressure and temperature. As the fuel enters the cylinder it self-ignites and burns rapidly, forcing the piston back down and converting the chemical energy in the fuel into mechanical energy. Dr. Rudolph Diesel, for which the engine is named, holds the first patent for the compression ignition engine, issued in 1893.
Vegetable oils gain interest as a biofuel. The early diesel engines had complex injection systems and were designed to run on many different fuels, from kerosene to coal dust. It was only a matter of time before someone recognized that, because of their high energy content, vegetable oils would make excellent fuel. The first public demonstration of vegetable oil based diesel fuel was at the 1900 World’s Fair, when the French government commissioned the Otto company to build a diesel engine to run on peanut oil. Rudolph Diesel later did extensive work on vegetable oil fuels and became a leading proponent of such a concept, believing that farmers could benefit from providing their own fuel.
Petroleum fuel shifts to the forefront. However, it would take almost a century before such an idea became a widespread reality. Shortly after Dr. Diesel’s death in 1913 petroleum became widely available in a variety of forms, including the class of fuel we know today as “diesel fuel”. With petroleum being available and cheap, the diesel engine design was changed to match the properties of petroleum diesel fuel. The result was an engine which was fuel efficient and very powerful. For the next 80 years diesel engines would become the industry standard where power, economy and reliability are required. Due to the widespread availability and low cost of petroleum diesel fuel, vegetable oil-based fuels gained little attention, except in times of high oil prices and shortages. World War II and the oil crises of the 1970’s saw brief interest in using vegetable oils to fuel diesel engines. Unfortunately, the newer diesel engine designs could not run on traditional vegetable oils, due to the much higher viscosity of vegetable oil compared to petroleum diesel fuel. A way was needed to lower the viscosity of vegetable oils to a point where they could be burned properly in the diesel engine.
Transesterification changes the game. It was a Belgian inventor in 1937 who first proposed using transesterification to convert vegetable oils into fatty acid alkyl esters and use them as a diesel fuel replacement. The process of transesterification converts vegetable oil into three smaller molecules which are much less viscous and easy to burn in a diesel engine. The transesterification reaction is the basis for the production of modern biodiesel, which is the trade name for fatty acid methyl esters. Pioneering work in Europe and South Africa by researchers such as Martin Mittelbach furthered development of the biodiesel fuel industry in the early 1990s, with the U.S. industry coming on more slowly, due to lower prices for petroleum diesel.
Pacific Biodiesel makes biodiesel production commercially viable. Our founder Bob King saw the potential (and developed the commercial-scale production technology) for recycling used cooking oil into biodiesel, a clean-burning biofuel that replaces petroleum diesel (fossil fuel). Bob created the first retail biodiesel pump in America at the Central Maui landfill back in 1995 – the year he and Kelly King co-founded Pacific Biodiesel. That revolutionary first plant on Maui initiated the entire biodiesel industry, which has since scaled up to more than 2 billion gallons of biodiesel produced in the USA in 2024.
Latest
Pacific Biodiesel Completes First “Sunflower” Biodiesel Delivery from Its Kauaʻi Ag Operations
On June 24, 2025, Pacific Biodiesel made its first delivery of biodiesel produced with sunflower oil from the company’s expanded agriculture operations on Kauaʻi to longtime customer Hawaiian Electric for its 50-megawatt Schofield Generating Station on O’ahu.
KIUC and Pacific Biodiesel Featured on KITV4
KIUC’s efforts to reach 100% renewable electricity production, supported by locally produced 100% renewable fuel supplied by Pacific Biodiesel, were recently featured on KITV4, reported by Kaua‘i’s own Lei Uʻi Kaholokula.
Employees Recognized on “Pacific Biodiesel Day”
On National Biodiesel Day, also known as Pacific Biodiesel Day in Hawai‘i, we recognize our 100+ employees statewide.