Run a Diesel Vehicle on Vegetable Oil

With a few modifications, you can run a diesel vehicle on vegetable oil to power your car or truck. People across the country are using conversion kits to retrofit their vehicles. Others are taking a do-it-yourself approach. Some burn free waste vegetable oil from local restaurants; others burn clean straight vegetable oil. But there’s a catch: Technically, it may not be legal.

| December 2007/January 2008

Marcos Markoulatos and Ty Martin, of Lawrence, Kan., both run their trucks on filtered waste vegetable oil.

Marcos Markoulatos and Ty Martin, of Lawrence, Kan., both run their trucks on filtered waste vegetable oil.

Photo by John Hardesty

You can run a diesel vehicle on vegetable oil. Vegetable oil can power your vehicle, but the effects on the environment are still unclear.

This may sound strange, but you can run a diesel vehicle on vegetable oil and nearly eliminate your use of traditional gas or diesel. For certain people, veggie oil could lead to major savings. Called veggie cars or grease cars, these vehicles have fuel systems modified to burn both diesel fuel and straight vegetable oil. The idea is actually a modern twist on the original intention for the diesel engine.

But even proponents say veggie oil is not for everyone because of the extra work it requires. Nevertheless, there is a small, but growing, part of the population that’s passionate about using grease to make their cars go. These people are drawn to this alternative fuel because it saves them money, gives them more control of their transportation fuel needs and makes a difference for the environment.

All this may sound too good to be true, and in some ways it is. Is it the most environmentally friendly alternative fuel? Should new vegetable oil or used grease be used? And here’s the real kicker: It’s technically illegal (see “Veggie Oil Vehicles and the Law,” below). So, before you start hoarding Wesson Oil, there are a few things you should consider.

Want Fries with That?

To get a sense of how this works, consider the example of Ty Martin. On Thursdays and Sundays the Lawrence, Kan., auto mechanic parks behind his favorite restaurant and heads inside for a hamburger and fries. As he eats with friends at the bar, kitchen staff fill a tank in the back of his truck with grease that was used to cook food just the day before. An hour later, truck and driver head home, both smelling faintly of burnt peanut oil. The used grease then propels Martin’s pickup all over town, all for free (except the food).

For Martin, burning vegetable oil means more than maintaining a dual fuel system. It’s a lifestyle, attracting the bohemian in a growing number of Americans who, for environmental, financial and/or political reasons, bristle over using fossil fuels for transportation. Whatever your motivation might be, if you have a diesel engine, it could run on cooking oil.

keith karolyi
11/26/2010 2:39:01 PM

Even if we use waste veggie oil for fuels, it still has an impact on the food supply since WVO is a widely used ingredient in making animal feeds. So far, the best solution I've seen is to use the veggie oil from algae. It grows faster and produces more oil per ton than anything else that grows on dry land. It is the one source that can produce enough fuel to make the U.S. energy independent without impacting food, farmland, water resources, or requiring massive re-engineering of cars and trucks. Best of all, fuel made from algal oil is carbon neutral: it takes as much CO2 out of the air to make it as it puts back in when you burn it. Some salt water species are even better oil producers than their fresh water cousins making it possible to produce fuel at sea. Best of all (in my humble opinion) small operators can get in on producing it in plants distributed widely all over the country. No need for Big Oil to control the taps. Our fuel sources can be local, reducing the need for long distance transport and will keep hundreds of billions of dollars in our own domestic pockets instead of sending it off to hostile foreign producers.

dan mathson
6/15/2009 3:16:52 PM

I wish people would get off the food or fuel argument when it comes to converting WASTE vegetable oil(WVO) to biodiesel. Using as waste stream to offset a very small part of diesel useage only makes sense. Biodiesel made from WVO will never amount to more than 1-2% if we converted all of it to biodiesel. But, just because biodiesel is not the green silver bullet to solve our alternative energy problem doesn't mean we shouldn't produce it. We need a whole host of technologies in the near term to reduce/replace our petro useage.

winter star
6/12/2009 12:29:48 PM

The more calories a substance has, the greater cost, including costs to grow, gather raw materials, and make the stuff. Consider, fats have been and are, valued foods: they embody energy stores, thus survival. Fats = food source valued by mammals. Harder to hunt or grow enough of it, it may be scarce and whoever goes to get it, may not come back. Fats as fuels works very nicely. But it will never work for billions of people simultaneously powering their vehicles. Just not feasible. It can only work for a few, to be a small part of the Bridge to Better Developments. Similar issues plague using alcohol as fuel. ANYthing burned to make a vehicle run is nearing obsolete. The planet just cannot sustain 6 billion people BURNing fuel to run vehicles, homes, industries. We must, very quickly, discover far better solutions. At present, the compressed air cars being developed have great promise as commuter pods and small work vehicles. There could even be kits to convert small older cars to use it.

criss kraus
6/12/2009 10:51:48 AM

My neighbor makes his own bio fuel. He uses a combination of his food SCRAPS and used cooking oil. He does NOT rob food off his table. He powers his tractor, backhoe, trucks and generator from this bio fuel. Granted the quickest and easiest way is to take the actual food item, but it can still be done WITHOUT doing this. And yes, he does have to filter more. But to say bio fuel takes food away from the table is false. Bottom line, we need to do something. Fossil fuels are finite. Fossil fuels are being consumed faster than the earth can produce more. Humans currently have no set of replacements for fossil fuels and all of their by-products. Like plastic, pharmacuticals, air and water filters, fertilizers, pesticides, over half of our composite materials and even pencils are all made from fossil fuels. Based on consumption rates from 2002 we have maybe 50-250 years before fossil fuels are gone from the planet. Then what happens? So, to me it is just a question of how hard are we willing to work for or pay for our fuel?

john adams_3
4/1/2009 10:30:21 AM

Well, Biodiesel and other Bio-Fuels are great. Problem is they are also food. There are still people going hungry in the world, and we are turing food into fuel so we can get around easier. There is a part of that that bothers me, a lot. No matter the source (corn, wood, switchgrass); the land used to grow fuel could be used to grow food. We humans can be pretty smart, I think we can find a better way.

1/4/2008 2:26:30 AM

Biodiesel is great, and being able to use waste vegetable oil is even better, but there are drawbacks. Biodiesel cannot be used in some of the newer diesel engines. The newest version of the Dodge 6.7L Cummins diesel engine can be ruined by using B100 (100% Biodiesel), and even a low level blend of 50% biodiesel and conventional diesel is tough on this engine. In cold weather, the biologically-based diesel has to be mixed with conventional diesel because it has a tendency to coagulate at very low temperatures. Using waste vegetable oil requires a substantial initial investment, especially if like me one is mechanically inexperienced and must depend on others to do all the installation work. Finding waste vegetable oil is labor intensive, and then the oil must be filtered and have any water removed. I haven't started doing this for myself yet, and buy my oil for $2 a gallon from a good source that filters and boils the oil to get all water content out. Changing the vegetable oil fuel filter is another expense that can't be ignored. But in the end, it is worth it to me. I think the diesel engine is the best thing we have in ending our dependency on foreign oil, but it is not mainstream enough to beat the drive to turn biological-based fuel sources into alcohol for use in conventional gasoline vehicles (which by the way produces 20% less fuel efficiency than using gasoline).

12/30/2007 2:22:32 PM

I do not see how this could be any more dangerous as far as emmisions are concerned being that its refined plant material as opposed to mineral material. this is just an uneducated guess. But either way, im going to go this route. of course, the government already has it ILLEGAL and considers it tax evasion. rediculous. can they control the wind yet? nope, but they'll find a way im sure. how about the sun? im going all in with venture. no way am i going to pass this up. bye bye electric company and high gas prices! The auto makers wont get behind it because of big oil companies. or any oil companies. they make too much money. the evil bottom line that drives the world. looks like florida is a destination im willing to go to live for this. they have sun and McD's there, right?

11/21/2007 2:45:14 PM

Just wanted to comment that I don't own biodiesel now ( as was indicated in the article. I do however own Utah Biodiesel Supply Too funny! Someone really double-checked the facts on this one.... -Graydon

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