
Posted October 15, 2004: In the renaissance
of renewable energy, biodiesel is pulling its own weight to
the forefront of the transportation, heating, and agriculture
industries. Both the U.S. Department of Energy (DOE) and the
USDA have led legislation and funding that recognizes the
usefulness of biodiesel derived from plant oils. It is a clean-burning,
carbon-neutral alternative to foreign petroleum fuel. Savvy
farmers are growing rapeseed and soybean to produce fuel oil
and nutritious animal feed. As we are faced with the imminent
switch from petroleum to alternative energy sources, the logic
of a biomass economy has got farmers adding new crops to their
acreage, while biofuel production sights are sprouting up
all over the world.
The facts about biodiesel
Biodiesel is an alternative to petroleum diesel that
can be used in any diesel engine and in most home-heating
oil furnaces with usually no conversions necessary. For those
farmers looking for an ecological alternative to fossil fuels,
biodiesel has become a popular fuel for greenhouses and tractors.
The physical properties of biodiesel are closely related to
petroleum diesel, so there are, at most, minor modifications
needed to change your fuel from petroleum to biodiesel. The
plant-derived fuel can be used as an additive by blending
with conventional diesel at any ratio or may be used on its
own. When a mixture of 20 percent biodiesel and 80 percent
petroleum diesel is used (a common formula), the fuel is called
B20. B100 is fuel consisting of 100 percent plant-oil-derived
biodiesel.
The advantages of using biodiesel include supporting domestically
produced fuel that helps the agriculture sector and drastic
decreases in the amount of polluting emissions. Some ‘do-it-yourselfers’
have gone completely off the petro-grid and no longer need
to buy fuel; instead they have recycled waste restaurant vegetable
oil into ‘grassoline.’ Manufacturing of biodiesel
scales a wide spectrum, from backyard bucket operations to
million gallons per year commercial operations.
In the United States, biodiesel has proven to be an effective
way for municipal fleets to cut emissions and clean up local
air quality. Shipping companies use biodiesel to lower emissions
and extend the life of their engines. Federal and state legislation
has helped make biodiesel more competitive by offering tax
incentives for using the renewable fuel. More and more state-run
buildings are being heated with biodiesel; likewise, countless
greenhouses are using the fuel to keep organic crops producing
year ’round.
Biodiesel 101
If you take vegetable oil from canola, soybeans, sunflowers,
poppies, algae, animal tallow or whatever else you can dream
up, mix it with alcohol add a catalyst (lye, for instance),
you create biodiesel and glycerin ( a useful product for soap
making and other industries).
Vegetable oils and animal fats are known as triglycerides.
The molecule is constructed of a glycerol backbone of three
carbons with a fatty acid chain bonded to each of the carbons.
Most plant oils consist of a mixture of fatty acids ranging
in size from 12 to 20 carbons; 16 and 18 carbon chains are
most common. Animal fats are similar to plant oil in that
they are both hydrocarbon chains (carbon chains with only
hydrogen bonded to each carbon). However, fats are made of
saturated fatty acids, and oils are unsaturated fatty acids.
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The unsaturated fatty acids in oils have double-bonded carbons
in the chain, which makes the molecule kink or bend. The saturated
fats are relatively straight molecules. At lower temperatures,
the straight molecules of fats settle on top of each other and
become densely compacted to form a solid, like butter. The kinked
oil unsaturated fatty acids need lower temperatures to organize
into a solid and therefore remain in a liquid state at room
temperature. This is why in northern climates plant oils are
preferred for biodiesel because buttery substances, made from
saturated fatty acids, can’t be fuel injected into an
engine.
As far as the fatty acids from plant oils and petroleum diesel
molecules line up, they both are long chain hydrocarbons.
A diesel engine doesn’t care which one you are burning.
In fact, the engine’s creator Rudolf Diesel won the
1900 Grand Prix at the French Exposition for running his new
invention on peanut oil. In Germany, Rudolf’s birthplace,
farmers have been running diesel engines on vegetable oil
ever since. One hundred years ago, John D. Rockefeller and
Cornelius Vanderbilt had other ideas for the energy industry
and helped forge an infrastructure based on the commodities
they had better control over, black gold (oil, that is) and
coal. So, until the late 1970s, the idea of using vegetable
oils or animal fats for fuel was a little-known secret. Today,
public awareness is probably the biggest hurdles to biofuels—that
and OPEC.
In the engine chamber of diesels, the pistons are rigged
to create a high amount of pressure. After the fuel has been
injected and the chamber pressurized, air is added to the
equation, then low-and-behold the oxygen in the air explodes
with the hydrocarbons forming carbon dioxide and water and
energy. The difference between gasoline engines explained
in part two
of the series and the diesel engine is the flammability
of the fuel. Gasoline and ethanol are shorter carbon chains,
and both are highly flammable; they are ignited in the engine
by a spark plug. Diesel fuels like biodiesel are not flammable
and are ignited instead by an increase in the chamber pressure.
In fact, there is enough chamber pressure in a diesel engine
that straight vegetable oil can be burned if modifications
were made to ensure the oil was heated to the proper viscosity
to get passed the fuel injectors. For more details on running
your car on vegetable oil, check out: http://www.greasecar.com/.
Car manufactures have based there engine designs on petroleum
fuel, but the need for alternatives has instigated an entire
economic model pillared by agriculture. Time will tell, but
vehicles could conceivably be manufactured to use vegetable
oil as the standard fuel, much like the flex-fuel vehicles
designed to run on ethanol. By using biofuels, proponents
of this industry say (including famous family farm advocates
Willie Nelson and Neil Young), we can eliminate the threat
of global warming and air pollution caused by human technology.
Check out the Institute for Local Self-Reliance (ILSR) ideas
on the carbohydrate economy http://www.carbohydrateeconomy.org/
.
Biofuel advocates point out that domestic crops could support
the transportation needs of the United States and keep tax
dollars and other resources from hemorrhaging out to petroleum-rich
countries. In progressing from petroleum to biofuels there
are major pitfalls to be avoided; as outlined in the first
part of this series , there’s always the potential
to jump directly from one pot of boiling oil into another.
An evolution in technology and business
Until recently, the popular understanding of our fuel economy
has been limited to how much people pay at the gas pump. Tracking
the money from distributors to shipping companies to drilling
companies to corporate and political investments is less than
exposed by media, even though our daily lives are so deeply
connected to this economic cycle. Even less information has
been publicized concerning the cycle of energy needed to perpetuate
our dependency on fossil fuels. The fact is, we have been
surviving on a false economy backed by dwindling supplies
of our energy source.
The price for petroleum does not account for irreplaceable
supplies of the resource. Furthermore, the cost is artificially
low because it is backed by subsidies that keep U.S. citizens
drunk on petroleum. Even though the biofuels industry is left
to compete with the false petroleum economy, the sheer logic
and health benefits of clean and renewable fuels have made
the alternative fuels industry profitable. Furthermore, political
uncertainties of oil producing countries are manifesting into
higher prices for petroleum at the pumps.
To remain sustainable and cost competitive, the biofuels
industry has to be energy efficient and rely on smart agricultural
practices that do not deplete water tables or exhaust available
lands. The most effective way to minimize energy costs and
sustainably manage inputs and outputs of the entire biomass
fuel system, from the seed to the fuel tank, would be to organize
a regional cooperation between farmers, producers, restaurants,
and distributors, says biodynamic canola oil farmer and biodiesel
producer Stephen LeBlanc. “Once you understand that
you can produce your own commodities, it makes more sense
to support local your local community while respecting the
natural world” says LeBlanc.
Farmers growing rapeseed, also known as canola, could co-op
a regional seed press, and offer area restaurants premium
oil at local prices to avoid too may middlemen and shipping
costs. The seed meal left over is a highly nutritious animal
feed ready to be sent a couple miles over to the local dairy
or pig farm. Biodiesel producers could pick up the used oil
from the restaurants and low-grade oil from farmers and process
the biodiesel from free or low-cost oil. For small-scale producers,
the sale of refined byproducts (glycerol, and fertilizing
compounds) could increase profits by 50 percent or more. Profits
from value-added products (such as soap) could make a substantial
contribution to the farms profits.
Grow Your Own- Rapeseed for fuel

So now that you are convinced that growing seed crops for
biodiesel and animal feed will be the perfect way for your
farm to increase profits while saving the world, lets talk
about growing. The following table lists popular oil producing
crops and their theoretical yields (check out http://journeytoforever.org/biodiesel_yield.html
for more):
| Crop |
kg oil/ha |
liters oil/ha |
lbs oil/acre |
gal/acre |
| Corn (maize) |
145 |
172 |
129 |
18 |
| Cashew nut |
148 |
176 |
132 |
19 |
| Oats |
183 |
217 |
163 |
23 |
| Lupine |
195 |
232 |
175 |
25 |
| Kenaf |
230 |
273 |
205 |
29 |
| Calendula |
256 |
305 |
229 |
33 |
| Cotton |
273 |
325 |
244 |
35 |
| Hemp |
305 |
363 |
272 |
39 |
| Soybean |
375 |
446 |
335 |
48 |
| Coffee |
386 |
459 |
345 |
49 |
| Linseed (flax) |
402 |
478 |
359 |
51 |
| Hazelnuts |
405 |
482 |
362 |
51 |
| Euphorbia |
440 |
524 |
393 |
56 |
| Pumpkin seed |
449 |
534 |
401 |
57 |
| Coriander |
450 |
536 |
402 |
57 |
| Mustard seed |
481 |
572 |
430 |
61 |
| Camelina |
490 |
583 |
438 |
62 |
| Sesame |
585 |
696 |
522 |
74 |
| Safflower |
655 |
779 |
585 |
83 |
| Rice |
696 |
828 |
622 |
88 |
| Tung oil tree |
790 |
940 |
705 |
100 |
| Sunflowers |
800 |
952 |
714 |
102 |
| Cocoa (cacao) |
863 |
1026 |
771 |
110 |
| Peanuts |
890 |
1059 |
795 |
113 |
| Opium poppy |
978 |
1163 |
873 |
124 |
| Rapeseed |
1000 |
1190 |
893 |
127 |
| Olives |
1019 |
1212 |
910 |
129 |
| Castor beans |
1188 |
1413 |
1061 |
151 |
| Pecan nuts |
1505 |
1791 |
1344 |
191 |
| Jojoba |
1590 |
1892 |
1420 |
202 |
| Macadamia nuts |
1887 |
2246 |
1685 |
240 |
| Brazil nuts |
2010 |
2392 |
1795 |
255 |
| Avocado |
2217 |
2638 |
1980 |
282 |
| Coconut |
2260 |
2689 |
2018 |
287 |
| Oil palm |
5000 |
5950 |
4465 |
635 |
In northern climates, rapeseed
is the highest-yielding crop, and, although it has particular
growing needs, it is a manageable crop for fuel production.
It is the preferred crop used to produce biodiesel in Europe
because it has high yield and is easy to grow. The seed contains
30 percent to 40 percent oil, and the seed meal is high in
nutritious proteins that make it an ideal supplement in animal
feed. It is part of the Brassica family and will pollinate
with mustard, radishes and turnips, so it needs to be isolated.
The seed is uncomplicated to sow; it likes moisture and is
broadcast on the surface, only 6 to 8 pounds of seed per acre
is needed. Aphids and army worms pose a problem. And, because
it is basically a tumble weed, wind damage could be a threat.
There are a few diseases that the crop is susceptible to;
these can be avoided by letting the hay winter over as mulch
rather than tilling it into the soil. Disease resistant varieties
are also available.
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Stephen Leblanc uses cow manure, green manure and crop rotation
to ensure nutrient-rich soil for his rapeseed crop. Canola
also likes about 20 to 40 pounds of available sulphur per
acres (a light gypsum application, which is 15 percent to
17 percent sulphur, will do the trick.) Overall, canola demands
less fertilizer than cereal crops or soybeans. The plant is
very effective at shading out weeds so doesn’t require
herbicides. Canola is also known to stimulate biotic activity
in the soil, which makes it a good crop to add into your rotation.
John Williamson, known as the sugar man in his neck of the
woods, grows sorghum and produces maple sugar and honey. He
has noticed a substantial increase in the bee’s honey
production, claiming “the bees really like the canola
flowers.”
Harvesting canola requires winrowing as with hay, or with
a sense for perfect timing you could direct combine your canola
field. Veteran canola cultivator Percy Schmieser prefers to
winrow his field when a quarter of the pods are brown. Once
the harvest dries up completely, the pods will shatter in
a combine and the seeds will easily be collected.
The oil is pressed from the seed. The remaining meal, if
it is organic, can be sold for $250 for about 1200 pounds,
or an acre’s worth of seed meal. Organic canola oil
can be sold to food co-ops and health-food stores for up to
$75 for five gallons (convention canola oil goes for approximately
$30 for five gallons).
Just do it: Tips to make your own fuel
Making biodiesel that is ready to use in your engine is a
relatively simple process that requires some precautions,
but nothing to deter the mechanically inclined. In order to
produce American Society of Testing and Materials (ASTM) quality
fuel, there are several purifying steps that are added to
a processor easily enough. Joshua Tickell has written the
bible of making biodiesel “From the Fryer to the Fuel
Tank” (check out http://www.veggievan.org/
). The book provides sturdy methods for getting started.
I teamed up with Scott Gordon, a chemistry professor at the
University of Vermont, and we gradually came up with our own
recipe while offering students great hands-on lab projects.
To make biodiesel, vegetable oil is mixed with alcohol and
a catalyst; usually a base, like lye. The batch is mixed for
about an 1 ½ hours, then allowed to settle. The glycerin,
base, alcohol and other byproducts will settle to a lower
phase; the biodiesel is a golden fluid floating on the top.
In order to get used to working with the chemicals and being
certain you are taking the proper safety precautions, it is
best to start off small, such as on the order of one liter.
You can quickly graduate from buckets to 50-gallon processors
and beyond, but it is always wise to begin with baby steps.
The major steps include:
- Gathering the oil
- Titrating the oil
- Processing the batch
- Purifying the biodiesel
- Distributing the fuel
The oil can be collected from restaurants, which are usually
more than happy to have their waste oil removed at little
to no cost (it saves them from paying the waste-removal company
a hefty fee). We have given restaurants 40 gallon hard plastic
containers that we recycle for a local olive distributor.
As far as shipping and handling of the oil, the Department
of Transportation does not have any stringent requirements.
At some point before the oil lands into your mix tank, it
should be filtered. We started out using two layers of steel
window screen, just enough to keep French fries out of the
mix.
Once you have gathered your main substrate, it is necessary
to find out the quality of the oil. When food is cooked in
the oil, which is usually canola or soybean oil, free fatty
acids from the chicken fingers, French fries, etc. accumulate
in the used oil. The free fatty acids will react with the
base you put in to catalyze the biodiesel reaction. By titrating,
you can determine how much base you need to add to neutralize
the acids and still have enough to catalyze the biodiesel
reaction, which in an organic chemistry book is called transesterification.
Titration is a basic chemistry procedure where an acid is
neutralized with a base and an indicator, usually phenyl pthalein,
changes colors at the neutralization point. By knowing how
much base is used to titrate an unknown amount of acid in
your oil sample, you can use simple calculation to assess
how much base you need in your reaction.
The reaction tank should be polyethylene plastic or stainless
steel, for trial runs most buckets will work fine. We eventually
switched to using conical tanks that allow for proper drainage
so we could take advantage of gravity to move our fuel around.
Copper, and PVC are not recommended for your plumbing; they
will last awhile but eventually corrode. The methanol and
base are caustic and corrosive, so polyethylene and stainless
steel are the only sure bet for long-term plumbing (brass
will give you a good run for your money and is a worthwhile
alternative to save you money until you are ready to set up
your 10-year plan.)
The alcohol you use can either be methanol or ethanol; both
can be made from biomass or bought from nearby chemical supply
stores. Store-bought alcohol will most likely be derived from
petroleum. We have decided to buy our methanol until we have
established our biodiesel market and can set up an ethanol
still. The alcohol is flammable, including the fumes. The
fumes are heavy and will fall to the floor but will escape
out the top of your processor. The area around the tank should
remain spark-proof. It is not a good idea to put a motorized
mixer directly over your tank—I have heard disaster
stories. Tickell recommends a pulley system, but explosion-proof
motors are another option.
Heating the mixing tank is a good ideas; up to 40 ºC
is recommended and will help you achieve a complete reaction.
Methanol boils at 60 ºC and ethanol at around 70 ºC.
You don’t want to get close to the boiling point of
the alcohol because it is not necessary and you will create
hazardous fumes. The alcohol is close to 20 percent of the
mixture. You need to have an excess to make the reaction work,
but after you settle out the byproduct it is a good idea to
try to recapture the excess alcohol, as it is one of the biggest
expenses in the process.
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The catalyst is usually a base, either lye (which is NaOH)
or potassium hydroxide (KOH). We like to use KOH because we
can turn the byproduct into fertilizer, whereas the sodium
in lye is less favorable to crops than potassium. We started
off using Tickell’s numbers for the catalyst but eventually
cut back on the amount of base. The base is mixed with the
alcohol until it is fully dissolved. The alcohol and base
are not friendly to your eyes, skin or lungs, so wear glasses,
protective gloves and work in a well-ventilated area without
the threat of sparks or open flames.
The alcohol and dissolved base are then mixed with the oil
and agitated for one to two hours. After mixing, the solution
is settled for eight hours. Two phases appear. The top should
be your golden biodiesel. At this point the fuel can be filtered
through a fuel filter and used in an engine or furnace. However,
to meet ASTM specification, residual methanol, glycerol and
base should be water washed out.
The byproduct, which settles on the bottom, contains glycerol,
base, methanol, unreacted vegetable oil, free fatty acids,
and whatever particles were floating in the used oil. We use
the byproduct to clean our equipment; it makes a great industrial
soap. We also purify the glycerol by vacuum distillation.
A portion of our waste is neutralized and sold to a farmer
who puts it in his methane digester to help feed the anaerobes
that turn cow manure into methane gas used for fuel.
Biodiesel is as biodegradable as sugar and less toxic than
salt. It does not require any major shipping or handling precautions,
as it is not flammable or corrosive. In fact, the DOT and
EPA treat biodiesel basically like vegetable oil. Our processor
designs recycle all of the inputs and compost the waste, so
we don’t have to worry about affluent waste or septic
regulations.
For more information on making your own fuel visit: http://journeytoforever.org/biodiesel_make.html.
Energy Independence
We have a golden opportunity to put the power of our communities
in the hands of the local farmers. The biofuels industry is
definitely growing and quickly turning into big business.
But as we have seen in the past, the interest of the people
concerned about clean water, air, is not the main priority
of profit-based corporations relying on economic ‘growth’
and short-term gains. As John Williamson put it “Without
fuel we would have no food crops, so we should have control
of it.”
It wasn’t long after I began working with biodiesel
that I met a number of other people in my rural agriculture
community doing the same thing. People began filling vital
niches within the growing industry. Today, the Vermont Biofuels
Association (http://www.vermontbiofuels.org)
gathers farmers, producers, distributors, economists, entrepreneurs,
organizers, waste-disposal companies and lobbyists for monthly
meetings. By working together, our community has its sites
set on controlling its own fuel destiny instead of having
it dictated to us. The entire community depends on fuel, and
we have the opportunity to make the industry a strong thread
between all of our diverse sectors. With some investigative
and clever business planning and community organizing, you’d
be surprised at how attainable a local, clean and renewable
fuel industry is.
John Orr is a biologist, ecological designer, organic
farmer and co-founder of Long Trail Biofuels. He is currently
working several projects including: algae biodiesel systems;
small-scale, closed-loop biodiesel processing; and bioplastics.
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