Advanced Search

Please click here to take a brief survey

Frybrid: How to Run Your Car on Grease
Sarah Rich, 15 Mar 07


What do you get when you cross hybrid transportation with local economic support and resource reuse? Frybrid. A small company in Seattle has developed a simple system for running any diesel automobile on vegetable oil discarded from the grease traps of restaurants. This is not biodiesel -- in which vegetable oil gets transformed into a highly viscous substance through transesterification; this is what many people call "straight vegetable oil" or "waste vegetable oil" (SVO/WVO) -- a direct line from the kitchen to the car.

In order to take advantage of this immediate and abundant fuel source, the car at the receiving end needs to be properly equipped to heat (and sometimes filter) the otherwise thick oil. That's Frybrid's specialty. They offer custom mods, DIY kits, and online instructions to get your diesel vehicle grease-ready. I went to visit Chris Goodwin and Forest Gregg of Frybrid in their shop in Seattle's Capitol Hill to get a tour of the conversion process and some inside info on the advantages of fryer fuel and the growth of the VO user community.


At first glance, you wouldn't know this place from the many other European auto repair shops around the neighborhood. A couple of old Mercedes sit parked on the concrete floor, a new VW Jetta wagon hovers overhead on the lift, tools and parts are strewn about (and a stout pitbull greets me at the door). But look more closely and you see stacked restaurant-style shortening containers, an old 25-gallon residential water heating cylinder, and a giant plastic storage container with a hose and a pump attached -- all components for filtering and distributing veggie oil. Over the past two years, Chris Goodwin Motorsport has almost completely stopped performing regular auto repairs as VO demand takes over their time. Chris estimates that they've converted around 250 cars, as well as selling kits to people all over the country and in parts of western Europe.

FRYBRIDDIAG4a.jpg So how does a car run on VO? Basically, the car needs a storage tank to contain the vegetable oil, a mechanism for heating the oil until it's viscous enough to run through the fuel lines, and a temperature sensor for monitoring what's going on in the car. All VO cars must be started on diesel or biodiesel, which doesn't need to be preheated. Once the veggie oil reaches 160F degrees (Chris estimates that this takes between 1.5 and 5 miles of driving), a computerized switch transfers the flow from the diesel tank to the veggie oil tank and you're running on pure grease until you turn the car off. Just before turning it off, another switch purges the veggie oil from the lines and restocks them with diesel/biodiesel so that the next time you turn the key, the cold car can start easily. The Frybrid website has a detailed explanation of the ingredients and steps required to convert a car. They make their system foolproof by installing indicator lights and override switches in the dash that ensure that the transfer back and forth occurs at the proper time, and that you don't clog your fuel lines with french fry oil. They estimate that their DIY kit, which runs about $1400, can be installed in a weekend, and Chris tells me that they've never met a diesel car they couldn't convert.


Once this process is complete, the car can run on vegetable oil from any source forever. This is one of the huge advantages over a biodiesel vehicle. Whereas biodiesel has to be carefully made with exact ratios according to the quality and pH of the specific batch of oil (and using some dangerous chemicals), a VO car can take anything as long as the food particulates and water have been filtered out (although word on the street is that Japanese restaurants have the gold of grease). This is not only more convenient, it's much cheaper. Most restaurants have to pay renderers to come haul away their waste grease, which means that they're generally more than happy to have someone take it away. It's mutually beneficial and free.

frylogoneg.JPG Salvaging and reusing oil that would otherwise be wasted from nearby eateries reveals another VO advantage over biodiesel. As biodiesel scales up, the industry is beginning to face criticism and concern over the impact of mass-producing biofuel from virgin agricultural resources. A lot of biodiesel is made from corn, soy and cottonseed, all of which are incredibly pesticide intensive and often highly genetically modified crops. The farming practices involved in cultivating these are, themselves, quite energy-intensive, as well as potentially destructive to biodiversity and groundwater. Then there is the transport of biofuels across the country or even across the world (Chris told me that a Washington biodiesel consumer found that it was cheaper to have biofuel ingredients shipped from Malaysia than to source them locally).

Plenty of sustainability advocates have voiced strong response to the booming biofuels industry this past year or so. Worldwatch Institute just released a new book entitled Biofuels for Transport, which offers "a unique global assessment of the potential opportunities and risks of the large-scale production of biofuels, [and] demystifies complex questions and concerns, such as the ‘food v. fuel’ debate" (the controversy over using food crops to run our vehicles). This is a debate in which Lester Brown has been a strong voice, calling for conservation and caution around throwing huge investment capital into agriculturally-intensive fuel crops.


This plays right into the advantage of WVO over SVO -- or using waste grease instead of fresh oil. By taking the local byproducts of our food supply as fuel, we close a loop that saves community restaurants some money and keeps us fueled up without fueling the potential destruction of industrial agriculture. Chris explains to me that restaurant grease really isn't a "waste" product; in other words, when it leaves the fryer, it hasn't lost all utility. Renderers call it "waste" so that restaurants will pay them for the service of hauling it away, but this substance actually becomes "yellow grease" and goes on to have another lifetime in animal feed and even cosmetic products (a disgusting reality that may warrant some investigation here in the future). This means that renderers make money twice on the deal -- they get paid to take it off restauranteurs' hands and paid again to have it taken off theirs. No wonder I'm told they're becoming some of the strongest opponents of WVO as fuel.

People often ask, though, if waste grease has a lower quality or the potential to clog up the car's system with impurities. When properly filtered, this is not a problem. At Frybrid, a coop of seven people collects, filters and shares a supply of Seattle's culinary backwash. In a 25-gallon water heater they heat the oil up until particulates and water sink to the bottom of the tank. Those are drained off the bottom and the good oil gets siphoned out to the storage tank, which they can access from a pump on the street just like a gas station. The drained materials go through the heating and filtering process repeatedly until all the usable fuel has been rendered.


To make it even easier, Frybrid will also add a built-in filter to converted vehicles so that you can literally pull up to your neighborhood Chinese restaurant and pour from their trap into your car. The heating and filtering becomes part of the internal process. Chris shared a great story of a family of five who asked to have a 21-ton, 40' luxury motor home converted to veggie oil. He did a custom conversion that included a 140 gallon clean tank, and a 70 gallon dewatering and filtering tank, as well as a 50' hose reel and pump to grab grease on the go, allowing mobile filtration of up to 140 gallons of waste oil per day. He reports that the family drove coast-to-coast over three months in the 6MPG mobile mansion, and at the end they'd traveled over 3,500 miles and spent just $47 on diesel. The family kept their own online diary of the journey (what they call a "wok-umentary" about their road trip running on "the fat of America") and they appear to be planning another epic trek this coming summer.

In addition to individual conversions, Frybrid has been branching into some deals with other companies to get their fleets running on WVO. He tells me about a start-up called Earth Friendly Moving in Southern California that's offering a new moving service geared towards elevating convenience and reducing waste in the home and office moving process. This is actually a very cool company in itself, employing a bit of service design to provide people with the supplies, storage and mobility they need to move without having to purchase and dispose of all kinds of packing supplies. They rent reusable boxes, delivery pallets made of recycled diapers, and packing peanuts made from recycled paper sludge and organic compounds. When you're finished unpacking, they pick up the goods and rent them to the next customer. Now they're going to get their moving trucks running on grease thanks to a deal with Frybrid, edging even closer to being a zero-waste company.


Having just returned from India, I couldn't help but think, as I stood in Frybrid's shop, about the obvious applicability of this model in a place like Delhi, where most vehicles run on diesel and much food is fried, pollution is terrible and low-cost or free fuel would obviously be make a huge difference to people who live on little. Because a big part of Frybrid's activity and community interface happens online, I asked Chris about what kind of interest has been demonstrated by internet forum participants from developing urban areas towards his DIY kits. He said that both India and Brazil have plenty of buzz going around biofuels (as has been demonstrated, of course, with the recent signing of the biofuels pact between the US and Brazil), but expressed concern about sending kits to people who might knock off his design and mass manufacture them at a lower cost for their region, with no profit or recognition coming back to Frybrid. The obvious question that arises from a response like this is: how do you balance wanting credit and payment on an original design against the desire to see a good, worldchanging idea spread and become accessible to more people worldwide?

And the obvious answer, it seems, would be a Creative Commons Developing Nations License, which would allow Chris to freely share his innovative idea with people in developing nations while retaining the copyright in places where he can feasibly make a living off of selling his kits and custom jobs. I have no idea whether the in-car conversion would translate in a place like Delhi or Sao Paulo, Lagos or Beijiing, but it seems like making the plans available for lowering the cost and pollutant load of transportation -- much like the Open Architecture Network makes building plans available to lower the burden of developing appropriate, low-cost housing -- could turn into an excellent opportunity for reexamining overlooked local resources and turning them into fuel for a sustainable future.


Bookmark and Share


A nice idea that has also been tried here in the UK. Unfortunately our tax authorities insist we pay much the same high tax that is on conventional fuel for any other type of oil if we use it as a fuel. As this includes secondhand cooking oil, there is little financial incentive to use this type of fuel.
We have had well publicised cases of people buying rapeseed oil from their local supermarket to use as fuel in diesel vehicles, then ending up in court for not paying the fuel tax on it.

Posted by: Al Raeburn on 15 Mar 07

I'm curious about the emissions factor. I've heard it's much lower than standard fuel, but still wonder what it is pumping into our atmosphere. Does anyone have any information regarding this?

Posted by: Deanna on 15 Mar 07

There is a lack of quality emissions data for properly modified vehicles burning vegetable, although Frybrid and other companies are remedying this.

It appears, at this stage, that the emissions are roughly similar to biodiesel. When compared to #2 diesel, burning vegetable oil will exhaust less hydrocarbons, carbon dioxide, and carbon monoxide, and of course no sulfur dioxide. Whether NOx will be higher or lower is unclear. While total hydrocarbons are expected to be lower, the portion of organically soluble hydrocarbons is likely to represent a larger share of total hydrocarbons compared to diesel.

Of course, as a biologically derived fuel, vegetable oil is arguably Carbon Neutral.

Posted by: Forest Gregg on 15 Mar 07

Good to use a waste resource but only a tiny number of cars could be run on WVO. Perhaps we could compound the energy effectiveness of waste VO. If we used the energy contained in VO to make PV cells or wind turbines we'd have energy for decades. I wonder as we become more health conscious whether we might run into another oil crisis? jim

Posted by: jim rees on 15 Mar 07

There has only been one case of someone being charged with tax evasion that I'm aware of here in the U.S.

This is an important consideration for those people considering it. If more people start using untaxed fuel they are going to start coming down on people. It doesn't make sense that some people should get to use the roads for free while others pay by for their use (via gas taxes at the pump.)

Posted by: Chip Thomas on 16 Mar 07

This company is to be lauded for its efforts to find a resource from what has otherwise been seen as waste.

But I am struck (only figuratively, I hope) by the monstrous vehicles you show running on vegetable oil. Yes, the emissions are better than gasoline, petrodiesel, or biodiesel, but there is still CO2 being emitted by these vehicles. Which brings up a couple of questions.

1. How many Japanese restaurants must there be to power, say, 10 per cent of our existing fleet? To be more specific, what is the capacity of this resource?

2. To what extent does the ginormous RV depicted above still contribute to climate change when it is getting its 6mpg on vegetable oil; that is, if we were to optimize vegetable oil use in vehicles, what effect would that have on greenhouse gas emissions?? It sounds like emissions data are sketchy at this point.

Ultimately, this post underscores the unproductive gyrations and contortions our culture is going through to hang on to the transportation model of the private internal combustion vehicle. To me, the fuel is not the problem: cars are the problem. Whether powered by vegetable oil or petroleum, the private automobile will continue to be the most energy intensive, wasteful, deadly form of transportation we have. It's time to accept the, um, inconvenient truth that to solve the immense problems of peak oil and climate change we will probably have to park our cars. We have to, as I think Pope Emperor Sterling has said, stop burning shit.

What Seattle needs is light rail (which is coming, slowly), not streets clogged with huge 4x4 trucks running on vegetable oil.

Posted by: John Baxter on 17 Mar 07

I have photos, schematics, more on my own system at Veggie Van Gogh's web site.

To answer a few questions posted here:

As Forrest noted, there are few studies done of SVO/WVO, partly because the fuel is so non-standard. One can make biodiesel to ASPE standards and test it in a way that is repeatable, but flitting from restaurant to restaurant does not provide you with a consistent base for testing! That said, the one study of which I'm aware tested virgin rapeseed oil, and found that most pollutants were about 5% worse by volume than for biodiesel, but biodiesel has about that much less energy by volume, so that would indicate that by distance traveled, the two are nearly identical. Which means that for everything except NOX, it is considerably better that petro-diesel.

Chip seems to think biofuel users are tax cheats. Another way of looking at it is that they deserve a tax subsidy for using, at considerable effort, a cleaner fuel. Many states allow a partial or even total fuel tax credit to alternative fuel users -- I think they all should!

John, there is roughly 3 billion gallons a year of waste vegetable oil available in North America. That could power nearly 10% of the North American diesel fleet. I agree, there are no silver bullets; we're all going to have to reduce the amount we drive as we begin the fossil fuel energy descent. But 10% is a big help!

My fear is that in our western love of the automobile, biofuels will supplant food production. It's already happening, as corn is being diverted from tortillas in Mexico to ethanol plants in the US. This is unconscionable! I do not believe in using food for transportation, unless it is the calories you eat to walk or bike!

The nice thing about driving on waste veggie oil is that it is putting a waste product to use. Permaculture teaches us that there are no waste products in reality. When a waste product appears, it becomes some other system's input. Currently most waste vegetable oil goes into pet food, which is not terribly good for our pets, either!

Biofuels from waste can help us make a graceful transition to a low-energy future. Such fuel use via individual initiative is to be lauded. Let's just not trade selling our souls to Exxon/Mobile for selling our souls to Archer-Daniels-Midland. In a low-energy future, energy sources will be diverse, distributed, and locally appropriate. Surely, using waste vegetable oil in such a manner is suitable!

Posted by: Jan Steinman on 17 Mar 07

Although I believe that using waste oils is definitely a good option these days it is important to conduct a lifecycle analysis.

Now I would be careful about the NOx we must remember that it is a particularly harmful substance in terms of acid rain, and eutrophication. Furthermore Nitrogen oxides are significantly more potent green house gases, by some estimates over 200 times the global warming potential of CO2. It would be important to get the numbers straight when evaluating the relative environmental impacts.

From what I have read while diesel fuel has less GHG impact it has larger effects on ambient air quality which is problematic in congested regions (health issues). Diesel vehicles on the other hand are often significantly less obsolescent than regular automobiles (most I've seen run over 300,000 miles), which is likely to mean less embodied energy over the lifetime.

It would seem like a good idea to attempt systems combining waste oil biodiesel with car share programs in a single system.

Posted by: Stelios Theoharidis on 17 Mar 07

Really excellent post. Readers might also dig this video of a guy in Oregon who does a walk-through of his system:

Posted by: Bren on 18 Mar 07

There's been lot of common concerns raised here, and I hope that I can respond to them all: limited market, taxes, Carbon contribution, NOx, and food vs fuel.

Limited Market:

Utilizing waste vegetable and straight vegetable oil is one component among many in the mix of alternative energies and energy conservation practices that will supplant current, finite, energy sources. How big a share it enjoy is not clear to me. I imagine that it will vary from place to place and depend upon climate, agricultural and dietary practices, and unpredictable technological and political contingencies.

Vegetable oil has many advantages that guarantee some future as an energy source, it's a liquid, it's distributed, it's not dependent upon extractive industries, it's biodegradable, it's nontoxic, existing vehicles can be retrofitted to use it, and perhaps most distinctive from most of other projected alternative energy sources, it is out of the lab and in the market and affordable to regular people.


Selecting vegetable oil as a fuel and paying road tax are two different, independent choices.

It's analogous to running a cash business and the relative ease in underreporting income to the IRS. There is a potential for abuse, but we don't confuse running a restaurant with being a tax cheat, and we shouldn't make the same mistake about home brewed fuels.

We encourage all of our customers to contact their local department of revenue in order to understand whatever taxes are due and how to pay them. Most states now have forms whereby people burning vegetable oil or home brew biodiesel can calculate and submit taxes due for use of public roads.

Carbon Contribution:

Vegetable oil is produced by plants by capturing atmospheric Carbon Dioxide and the sun's energy. The burning of that fuel releases the carbon dioxide back into the atmosphere. The same Carbon circulates through the atmosphere, through the plant, out of the engine and back into the atmosphere. It does not add to the total amount of Carbon in the atmosphere. (A somewhat idealized picture as it does not account for all the inputs that goes into the growing, processing, and distribution of the oil).

Burning petroleum based fuels puts back into the air Carbon that was locked underneath the ground a long time ago. The Carbon is pulled out the bank and the total Carbon in the atmosphere increases.

So, while that big RV pumps out tons of Carbon Dioxide while it's running on vegetable oil, it's global contribution of Carbon is very low since the actual chemical Carbon content of the oil doesn't matter, as that all came from atmospheric Carbon. The Carbon contribution is just the petroleum inputs that went into the growing, processing, and distributing of the oil before it went into the RV.


I would be much obliged if you could cite that comparison of SVO and biodiesel.

Fuel vs Food

Do you think that it is unconscionable to wear cotton, drink beer or wine, or use natural pigments because the land that produced those crops could have been used to grow food. Do you think that it is evil to enjoy peaches, when soybeans give more calorific bang for the buck per unit of arable land?

In any case, while it is true that corn prices have risen because of increased ethanol production, but all market projections (and the history of boom and bust of industrialized farming), suggest that they will fall back to 2005 levels within a few years.


Posted by: Forest Gregg on 19 Mar 07

WVO would not sufficiently replace our current use of conventional fuels, but - couldnt that be a good thing? Rather than having the worlds economy linked to the price of its primary energy source, dispersing that burden to several different and ecologically friendly resources could result in lower energy costs and even more products being introduced as alternatives. One thing that truly worries me about oil is how much we depend on it. Beyond fueling our vehicles and heating our homes, there are so many other applications for it which are less apparent. Would it be wise to turn over that role to any other single resource?

Posted by: Sara on 23 Mar 07

this is a great site, I would like to send it on to others, it would be good to have a button such as e-mail a friend .....

Posted by: cindy on 29 Mar 07

With alternative energy plans, shouldn't 10% of our current transportation be sufficient? Considering the benefits, such as a closed loop system, recycling leftovers instead of using fresh food, etc. I believe that is a considerable incentive to reduce individual transportation by a lot.

Posted by: Astrid on 2 Apr 07



MESSAGE (optional):

Search Worldchanging

Worldchanging Newsletter Get good news for a change —
Click here to sign up!


Website Design by Eben Design | Logo Design by Egg Hosting | Hosted by Amazon AWS | Problems with the site? Send email to tech /at/
Architecture for Humanity - all rights reserved except where otherwise indicated.

Find_us_on_facebook_badge.gif twitter-logo.jpg