by Bob Griesberg
It was time for another midnight raid for liquid gold. I needed it bad. Now. My friend and I were dressed entirely in black. Everything was packed and ready to go: portable 12-volt diesel pump, 40 feet of garden hose, 100 pounds of kitty litter, old bath towels, shovel, broom, spare screen filter and three 55-gallon steel drums. Next stop: an unnamed fast food establishment.
You need to understand that this is not my first choice. This specific fast food dealer has only fair quality gold, but all my favorite spots were dry, and I needed it now.
So what is this liquid gold that one can get at restaurants? Waste vegetable oil (WVO). I am writing to share the secret of free fuel. I recently converted my Ford F250 diesel to run on this liquid gold. And you can convert your diesel too, with a little money, a few tools and lots of determination. But you can’t be afraid to get a little dirty.
we pulled up to the trash area of the restaurant, the smell of greasy fries
was overwhelming. It was as if we were camouflaged, because my exhaust smelled
like fries too. It was two in the morning, but the parking lot was lit up like
it was midday. We had to work fast and hope that no cops drove by.
This establishment had non-hydrogenated oil, we knew through our advance intelligence
gathering. Hydrogenated oil is solid at room temperature. It is not suitable
for use as fuel, particularly where the climate is cool, like ours in Minnesota.
I had sampled this oil discreetly earlier in the day. I knew after a few hours
of settling and cooling that the quality of the oil was fair. I would have to
filter carefully for water and particulates. But I needed fuel now, so I would
have to take what was available.
I pulled up to the grease pit, popped the hood and ran to the front of the truck
as my partner ran around the back. As I lifted the hood, he appeared with the
12-volt diesel pump. I attached it to the battery as he got the hoses and screwed
them onto the pump. I dropped the end of the hose with the screen filter in
the grease pit as he dropped the other end into an empty 55-gallon drum. I hit
the switch and the pump started to suck. In a few seconds we heard the beautiful,
tinny sound of grease hitting the steel floor of the drum. Liquid gold.
Ten minutes later we had one drum full. We kept our fingers crossed that no
police would appear. We were nearly half done, as long as we didn’t spill
oil in the lot. Even though we steal other people’s garbage, we are not
irresponsible. Waste vegetable oil spills are slippery for other drivers, pedestrians
and urban wildlife. We had to be careful. Staying to clean up a spill would
almost ensure that we would be caught.
the second drum was full we switched the hoses around to suck the grease out
of the 3rd 55-gallon drum, and pump it into the grease pit. About 30 percent
of the oil collected is unusable, so I was returning my waste to the original
Feeling the crush of time—and fearing arrest—we began to pack up.
As the hoses were being raveled, oil began to leak out of the ends, so we held
them over the grease pit as we rolled them. Just about done, we had spilled
10 or so ounces on the asphalt. As I wrapped the hoses in plastic and threw
them in the bed of the truck, my friend threw a shovelful of kitty litter on
the spill and worked it around. I grabbed the broom, we swept it up and deposited
the mess in the dumpster. We drove off, smelling of french fries, but we were
free. This is where the hard part started.
Back at my workshop we pumped the oil out of the drums in the truck into a special
drum that I had modified with filters made from cut-off, sewn-shut jeans legs,
a rotary hand pump and a 240- volt water heater element and thermostat run on
120-volt power to slowly warm the oil so it could filter faster.
After the oil was filtered, we pumped it into storage drums. From these drums
I pumped it into my fuel tanks. With my stock diesel tank and auxiliary tanks
that I had modified for waste vegetable oil, I have the ability to drive more
than 1,300 miles while paying for one tank of diesel fuel. If I filtered on
the fly, like I would tonight, I could go even further, because the diesel fuel
is only used to start and shut down the engine.
Rudolf Diesel invented the compression engine, now known as the diesel, he tested
it with multiple fuels. He eventually concluded that the engine could function
on just about any liquid fuel. Peanut oil was one of the best fuels. It lubricates,
unlike diesel fuel, which is corrosive. As a result vegetable oil may lead to
longer engine life. Power and miles per gallon usually remain unchanged, but
a very few people report a slight increase in horsepower, which is theoretically
Vegetable oil is a great fuel option in warm climates. In cool climes, the oil
begins to solidify as the temperature drops. This means that the fuel needs
to be heated so that it is a thin liquid before being delivered to the fuel
In the period between WWI and WWII, the petroleum industry experienced a great
expansion. The American dream of a car in every garage was well on its way to
becoming a reality. Gasoline was plentiful and cheap. And the petroleum industry
had all the waste products of the gasoline refining process to dispose of. One
of these waste products was just right for diesel engines in most climates.
It is now known as diesel fuel. The petroleum industry aggressively marketed
this waste product as a fuel for diesel engines. Because the oil companies owned
the gas stations, it became the standard.
Most large diesel trucks come standard with tank heaters to keep the diesel
fuel from “gelling” at temperatures below 40 degrees. Heating the
fuel is the foundation of many conversions. The magic number is 160 degrees
Fahrenheit. Above this temperature, non-hydrogenated vegetable oil’s viscosity
is within acceptable limits for use as fuel in the diesel engine.
When I was 15, I helped my father change the oil on a 1974 Ford Maverick. That
was the last car I worked on—until I undertook my waste vegetable oil
conversion project. The conversion process entailed designing and installing
an auxiliary heated tank, auxiliary heated fuel system (including a heated filter),
and switches which allowed me to choose between the diesel fuel and the vegetable
I could never have done this alone. My friend and mechanic did much of the work
(and all the hard work). My friend’s lovely wife tolerated my theft of
her husband for hours on end. I made mistakes in design and installation, but
they have been solved now.
conversion is the easy part of the equation. If something is free, there has
got be a catch, right? This fuel is free, but the savings comes at the expense
of sweat, grime and the pungent aroma of chicken, French fries and on rare occasions,
beef. Ironically, this messy work is rather exciting. It is a thrill to discover
a grease pit that has been properly covered, filled with non-hydrogenated oil,
and is clean and accessible. With quality oil like this, there is much less
effort involved to adequately filter what is ultimately a greater amount of
fuel. I’ve learned to be picky and to pass on inferior oil. But tonight
I did not have the luxury of waiting.
Usually I would not steal oil. It is too easy to get caught, and it is not worth
it when the owners of this trash often are more than happy to give it away.
Every restaurant that fries food faces the issue of disposing of the waste oil
from the fryer. In the end, most have to pay to have it hauled away. And pay
they do. For some it may be only $10 a month, for others it may run into the
As a retired dumpster diver, I like to sample oil discreetly from various grease
pits about town. When I find one that has quality oil, I decide to visit the
restaurant at an off-peak time. After ordering a small meal, I ask to see the
manager. This is a tactic that restaurant supply sales people use, so some managers
may at first think that I am trying to sell something to them, rather than take
something from them.
When the manager comes, I introduce myself and explain that I have converted
my truck to run on waste vegetable oil and I understand that they have to pay
to have their waste oil disposed of. I propose that they can save money if they
allow me to take some of the oil. Most managers will go for it. To earn their
trust, I keep the grease pit area clean, and I don’t distract their employees.
It takes some work, but it makes sense economically and environmentally to get
free fuel at a time when gasoline and diesel are not only more and more expensive,
but also scarcer.
As scientists debate exactly how much oil we have left and when world production
will peak, one thing is certain, we have less oil today than we did yesterday.
If we have not already, soon we will have extracted and processed half of all
the oil on Earth. From that point forward, oil supplies will be lower than the
demand for cheap fuel. Keep in mind that China and India, the two most populous
nations on earth, have yet to put two cars in every garage. We are in for a
long and very expensive ride. And so is the climate.
is what pushed me over the edge, why I decided to convert my diesel vehicle
to run on an alternative fuel, ultimately deciding on waste vegetable oil. At
first I thought seriously about buying “Bio-diesel” at the pump.
This “Bio-diesel” is only a certain percentage of bio-diesel and
the greater portion is regular petroleum diesel. B5 and B20, for example, are
only 5 percent and 20 percent respectively, of vegetable-based diesel fuel,
but they are often marketed under large signs proclaiming “Bio-diesel”.
I was tempted to join the Twin Cities Bio-diesel Collective (tcBioDiesel.com),
pay my yearly dues and buy quality bio-diesel at fair prices. I like the idea
of what they do: deliver a high quality product that is less harmful to the
environment, and make it available for a fair price. I question whether they
are a co-op, in federated buying power, member ownership, worker/owner, or any
other form I know of. But they offer superior quality vegetable oil bio-diesel
up to B100 (100 percent vegetable based bio-diesel) or straight vegetable oil
for fuel, and at a discount for members. You can’t buy B100 at the pump.
I even bought a bio-diesel processor from a friend who needed money for land,
and couldn’t transport that huge thing out West. I have very little scientific
experience, and although it can be done safely, the danger involved in processing
bio-diesel, and the problems inherent in experimenting and obtaining consistency
in results, caused me to decide against making my own bio-diesel. Currently
my processor is out on loan.
choices were clear at that point. Purchase bio-diesel through a middleman, from
the same company that produces petroleum diesel fuel, or modify my vehicle to
run on society’s waste. In my continuing research, I discovered a recent
study that shows that bio-diesel and diesel both have energy returns that are
lower than their inputs.
David Pimentel, professor of ecology and agriculture at Cornell and Tad W. Patzek,
professor of civil and environmental engineering at Berkeley, conducted
a detailed analysis of the energy input-yield ratios of producing ethanol
from corn, switch grass and wood biomass as well as for producing bio-diesel
from soybean and sunflower plants. Their report is published in Natural Resources
Research (Vol. 14:1, 65-76).
In terms of energy output compared with energy input for ethanol production,
the study found that: Corn requires 29 percent more fossil energy than the fuel
produced; Switch grass requires 45 percent more fossil energy than the fuel
produced; and wood biomass requires 57 percent more fossil energy than the fuel
In terms of energy output compared with the energy input for bio-diesel production,
the study found that: Soybean plants requires 27 percent more fossil energy
than the fuel produced; and sunflower plants require 118 percent more fossil
energy than the fuel produced.
In assessing inputs, the researchers considered such factors as the energy used
in producing the crop (including production of pesticides and fertilizer, running
farm machinery and irrigating, grinding and transporting the crop) and in fermenting/distilling
the ethanol from the water mix. Although additional costs are incurred, such
as federal and state subsidies that are passed on to consumers and the costs
associated with environmental pollution or degradation, these figures were not
included in the analysis.
took a look at the data on pollution levels, and it was clinched. Vegetable
oil was safer, had a greater energy return in relation to inputs and overall
polluted less than even bio-diesel (go to GreaseCar.com/Tech
to see emissions comparison test results). Waste vegetable oil has already served
its purpose. Its commodity life was over (nearly). Anything gained by it was
a bonus. So aside from the time spent filtering, it is free fuel, with less
pollution, and a fun story to tell.
For those of you who are interested in converting your diesel vehicles (not
gasoline engines) to run on waste vegetable oil, on October 7 through 9 the
Church of Deep Ecology is hosting a hands-on workshop in which participants
will convert a diesel Volkswagen Rabbit to run on waste vegetable oil. For more
information, go to ChurchOfDeepEcology.org/Diesel2Oil
or call 1-800-862-7031.
Craig Howard, of Fatmobile SVO Systems (GeoCities.com/VWfatmobile),
the instructor for the workshop, has converted many Volkswagens. He is a specialist.
He has refined his conversions again and again, and it seems that many of the
buy-a-kit and full-service conversion companies have borrowed from Craig’s
expertise. But he would be slow to admit it, if at all.
If you decide to convert your vehicle, the cost of the training will be covered
in the first fifty gallons at current prices. Not a bad deal to break away from
the man, at least partially. ||
Additional sources of information on WVO conversions:
Linscott from Alexandria, MN has developed how-to files for the do-it-yourself
set, and has done an extensive amount of research. He has links to most information
on the web about WVO conversions. Visit his website at: VegOilConversions.NetFirms.com.
Infopop SVO forum is an active internet-based straight and waste vegetable
oil forum. It can be found at:
If you are interested in purchasing a conversion kit, or having a kit installed
professionally, the following companies may be of interest: