Here comes a long sermon to explain why I really like the idea of running on vegetable oil. If you?re interested in the technical aspects only, start reading at ?basic knowledge on Diesel motors?

Why veggieoil ???

I love travelling and a big part of my life is sitting behind that wheel and steering down the open road. Often the main expense in my budget is Diesel. I pay more money for fuel than for food, communication or tools. I wouldn?t even mind that, what bothers me is the fact that half of that money goes straight to the government and the other half to the oil industry. So in order to live my life the way I want to live it, I have to pay off the two sickest fattest bastards in the whole wide world. And I don?t like that. 

I have never been much of an environmentalist, but over the years it started dawning on me how destructive in every respect the world's energy system is right now. 
I don?t want to go into the details of the green house effect and global warming here, because the facts are widely known. But the knowledge of the problem doesn?t help much without the knowledge of a solution. And here it is:

By using vegetable oil instead of Diesel oil to power a motor, we only release as much carbon dioxide into the atmosphere as the plant has absorbed while it was growing. Actually a little less, because only the plant?s seed are used to produce the oil. If the rest of the plant is conserved, e.g. by turning it into construction material, we even have a way of pulling carbon dioxide out of the atmosphere. 
This could be a brilliant example for succesful surviving within the desaster areas of the 21st century: try to live within a cycle that regulates itself and leave as little a trace as possibles while encouraging a radical change that enables us to correct the mistakes of previous generations. 

Either the consequences of the green house effect will become a lot more obvious and prevent us from using more fossile ressources, or the wars waged over them will reach a level of absurdity where in order to steal one barrel of oil the US will have to burn two barrels in their jetfighters to kill everybody who?s standing in its way. Whatever happens first I don?t know, but I know that at this point we better have enough alternatives ready or else we will end up with a lot of new nuclear power plants. 

Another so called alternative is burning hydrogen in fuel cells, which sounds really slick but doesn?t convince me at all: Nobody has ever told me about a good way of producing hydrogen yet. Although its amount is theoretically unlimited, in order to produce it (split water into its components hydrogen and oxygen) you have to invest exactly the same amount of energy that you get out of it in the end. It?s a common misconception, hydrogen is a mean of transporting energy, not producing it. Another thing is: It?s highly dangerous to handle and transport. I have a sneaking suspicion that it?s not more than the oil companies? attempt to save their fuel distributing structure by introducing another substance which is maybe more or less clean, but still requires their structure of processing and distribution. Which leads us to the next point: 

Energy, power and control

The structure of the energy system. What we?re used to now is that a substance is torn out of the Earth somewhere and then transported over thousands of kilometres to be burnt somewhere else. The transport means a lot of extra pollution, danger and wasted energy. But it also means a lot of money to be made and a lot of control to be exerciced. Whoever controls the resources and the transport can force everybody else to pay for it. The outcome has three letters. 

A friend of mine pointed out that using up all the oil is not just straight up stupid, but does follow a certain logic. If you have succesfully consumed the oil you stole from the rest of the world, but guarded your own reserves in the meantime, you will end up with a huge strategical advantage.

Growing your fuel is a whole different concept: Instead of sitting there waiting for somebody to grab it, the fuel is raised in a plant which needs space and time, to grow. It?s spread out and in order to turn into carburant, it has to be harvested and processed in an oil mill. Then it can be burnt right on the spot. Try and steal a field of sunflowers, you might wind up working more than you expected, and even if you succeed – they will come back the next year. This means that we have a source of energy that is spread out not only in space, but also in time and therefor very hard to control. Some European governments try to prevent the use of plants to produce carburants, but the example of other plants shows, that controlling a plant that anybody can grow is a very tough business.

Decentralised production of Energy also allows a lot more local Autonomy. The energy structure of a country corresponds with its political structure – centralized and concentrated energy allows and requires a strong authority to manage the distribution and handle the risks. 

The wars of the 21st century will be waged over access to energy, food & water. If we have our own sources, which constantly reproduce without creating an excess that is worth stealing, there is a small chance for us to live in peace. 

Corporations and the environment 

Besides the geopolitical there is the corporate structure. Eight of the ten largest corporations in the world are engaged in the car and oil industry. 

When I visited a trade fare for alternative energies not long ago, I wasn?t too surprised to find Shell and British Petroleum selling Photovoltaic Panels in competitive prices and quality. 

I think it?s important to understand that big corporations do not have a personal interest in destroying the planet. It is true that they have absolutely no sense of responsibility and will continue to do so as long as we let them get away with it, but on the other hand they have the blueprints for ecological solutions in their drawers and will pull them out as soon as they?re forced to. Public pressure and also public demand for such products is a good way to push this change forward. But to build up the pressure, a small minority will have to demonstrate that the solutions actually work. 
The same thing is true for the car industry: The only thing they?re interested in is selling a new model every few years. If greater efficiency is a way to do so, they will of course aim for it. But only so much at a time, to make sure that the development will last a few car generations.. This explains why inventions such as the three litre Diesel (a car that consumes three litres on 100 kilometres, or gets 72 miles out of a gallon) have just come out recently, although they have been technically possible for about 25 years. Not only does this logic slow down the technical development, but it is a big problem in another respect: 
Producing a car consumes a lot of energy as well, and wastes a fair amount of labour, water, and other resources. The less people or freight it moves and the more time it spends sitting around, the worse that relation gets. However, it keeps the market going. 
It is also important to point out that some of the latest developments which are sold under the label ?ecological? are just straight up bullshit. Some companies produce cars out of aluminum, and although they?re looking pretty slick, the weight reduction will never make up for the energy invested in producing the aluminum. They are also a lot harder to repair, which makes their parts more likely to be replaced. 

Basically I propose a double strategy: Develop the alternatives for ourselves to gain Autonomy and force corporations to adopt progressive solutions by creating public pressure and demand for them. 
In the end I have no doubt that big corporations are a big waste of time and resources and that we will have to overcome their logic at some point. But I also feel an urgency to force them to adept. If Shell sells millions of Solar panels each year, I still have more than one reason to despise them. But I do appreciate the amount of clean energy being produced this way. 

The use of vegetable oil is not the key to solve all the world's problems right on the spot. But it's a very interesting way of using solar energy that the plants kindly transform and store for us. Other than photovoltaic systems, it allows us to power strong applications, such as motors in vehicles or generators, without using batteries or transformers. 

However, a change to a truly sustainable way of living will only come with a change of the patterns of consumption. That's why the search for technical solutions is only one half of the game. 

In the end only a drastic reduction of our consumption will allow us to produce enough energy in a sustainable way. I think about 10-20 % of today's consumption will be enough to maintain a decent standard of living, once we have overcome the globalized production and transportation 
of useless crap.

The application of alternative energies is also important, because it creates the consciousness that producing clean energy is very well possible, but also does take a certain effort. It can't be stressed too much that this effort doesn't have to go along with tiresome restrictions. 
Having access to endless power on demand does not make the individual stronger (although it feels quite potent on first sight), but dependant, neurotic and weak. 
But the knowledge that the necessary energy to survive can be created without further destroying the environment is very empowering and satisfying. 

Also don't forget that often the plain fact that somebody is working on a problem does help to solve it – even if it turns out that the solution happened somewhere else. But the Revolution is first of all a fuckload of work.

Technical terms: 

Vegetable oil: 
Is produced by pressing the seed of different oil plants. The most common are sunflower and rapeseed, but also lineseed, soy, palm and many other plants can be turned into oil for the use in Diesel motors, after it has run through filters the size of 5 microns ( 5 micrometers, or o,ooo oo5 meters, which equals .000197 inches ) or less. Since it is much thicker than Diesel, it has to be either preheated or mixed with Diesel in order to burn properly and not cause any damage. There are countless ways of pressing and refining. The majority of people I talked to is in the opinion that cold pressed oil that contains as little water and slime as possible works best. 

Biodiesel:
Chemically ?Fatty Acid Methyl Ester?, is made by adding alcohol and a catalyst to vegetable oil and separating the glycerin (also called glycerol). This process is called transesterification. The result is a fuel that is much thinner than the original vegetable oil and ignites much easier. It can be used instead of Diesel fuel without any changes on the engine, but it has to be assured that all hoses, tubes and fittings are made of materials that resist alcohol. In some countries access to alcohol in sufficient quantities can be problematic. Also the production of Biodiesel requires control over the chemical transitions and a certain amount of energy, time, space and experience. 

Chipfat:
Any kind of waste vegetable oil can be used the same way as fresh vegetable oil, if proper filtring (5 microns or less) and separation of water and fat from the oil can be assured. After the filtring, it can be used straight away or turned into biodiesel. 

Different approaches in European countries: 

It?s interesting to see how different cultures bring out different ways of dealing with the problem. 

The Germans collectivise the production of the carburant, exhaust their minds about various preheating systems and benefit from a rather progressive government. The French in the meantime, strong believers in the idea of Autonomy and opponents to a state that relies on centralism and nuclear energy like no other in the world, pointed my attention to the quality and production of the oil itself. They prefer to run their own oil press, even if it produces not more than 3 litres per hour. 
Since the European Union pays massive subventions for growing sunflowers (asking why opens up a whole new rabbithole, but I haven?t found a convincing answer yet) plenty of them grow, often without even being harvested or used. The seed can be turned into high quality carburant. Their remains give off excellent fodder for animals, whereas the remains of the plant can be turned into bricks to provide insulation for buildings. By working a plant into a building, the carbon dioxide that it has absorded is stored and will not be released untill the material is burnt or rotts away. This creates a possibility to pull carbon dioxide out of the atmosphere. Using plants as a carburant slows down the process of Co2-release that leads to the green house effect, but also using them as construction materials is a way to reverse it !

The group tournesol (www.tourne-sol.org) is touring with a generator that demonstrates the use of sunfloweroil and an own oil press. 
The societe Valenergol (www.valenergol.free.fr) has produced sunfloweroil for the use in cars since 1996 and is now accused of not paying fuel taxes. 

In Germany, there is no state hassle and a booming scene of 10 or 15 companies professionally convert an increasing number of vehicles every day to run on rapeseed oil. There is a network of fuel producers and an established standard for the carburant ("Weihenstephaner Standard"). Biodiesel (also called RapsMethylEster, or RME) is tax reduced and can be bought at some gas stations for about 10 cents less per litre than regular Diesel. But most car producers have declared only a few of their models (usually the newer ones) to be save to handle its alcohol content. 

To run a Diesel motor on vegetable oil is very well possible if you have basic mechanical knowledge. It doesn?t take a certified engineer to do a conversion, but also running a motor on something that it?s not supposed to be running on is not a joke. It should be done carefully. 
The problem is that almost anything works for a while, but insufficient preheating or bad quality fuel will cause damage in the long run. Visualize vomiting into a saucepan and leaving it on the stove over night – this is roughly how the inside of your motor will look like after 10.000 kilometres on poorly burnt veggieoil.
It is true that both vegetable oil and biodiesel are biodegradable and not hazardous to the environment, but especially in the vicinity of a running motor they can easily cause problems or wash toxic grease or oil from the motor into the Earth. That's why the basic common sense law that nothing should ever be spilled apllies here as well. 
I highly recommend having a diary which includes all changes made on the motor, the types and qualities of vegetable oil being used and all observations you make on the behavior of the motor. This will give you a good record of your work and a much better chance to identify long term cause - effect relations. 

Basic knowledge on Diesel motors:

Other than motors running on gasoline (uk: petrol), Diesel motors require no spark plugs for ignition. The motor sucks in air and compresses it. This heats the air to a temperature above the flaming point of the fuel. That?s why the compression is higher and a lot more important and it takes more force to start a Diesel. 

 Two different types of Diesel motors: 

Indirect Injection, or prechamber motors: The fuel is first injected into a prechamber above the actual cylinder. It ignites here and then fills the cylinder. The prechamber can be heated with glowplugs to help starting the cold motor. If your motor has glowplugs (not to be confused with sparkplugs), it?s indirect injection. These motors run a little smoother and are commonly used in cars and light trucks. The injection pressure is relatively low, about 120 bars (1740psi)

Direct Injection: The fuel is injected directly into the cylinder. If your motor can always be started straight away and has no glowplugs, it?s direct injection. These motors run a little more efficient. They?re common in boats, heavy trucks and also small generators. The injection pressure is higher, about 180 bars (2610psi) and more. 

Fuel Injection is a very important point and the key to the efficiency of a Diesel motor. It was one main obstacle in developping the motor and it wasn?t untill Robert Bosch invented injection pumps which were both small and fast enough, that the motor could be used in cars and trucks. 
The pumps are quite complicated, since they have to inject a precisely defined amount of fuel at exactly the right point in time with very high pressure under constantly changing circumstances. Even for qualified mechanics reparing them is a nightmare, because it requires specialised tools and knowledge. If you ruin a pump, chances are that you will have to replace it, which is not cheap. 

There are two kinds of injection pumps: Rotary and In-line. Rotary pumps have only one cylinder that builds up the pressure and a rotating part which distributes the fuel to each fuel line. The fuel lines are assembled in a circle or square pattern on the head of the pump. In-Line pumps have an own cylinder for each fuel line and look like a little motor. All the fuel lines are assembled next to each other. 
Also, In-line pumps usually consist of a little pump which is only responsible for pumping the fuel around and a big one which creates the pressure for the injection.

At the moment various new injection systems are introduced to the market. The TDI (turbo direct injection) that has been used by Volkswagen for a few years seems to work excellent with vegetable oil, for other systems such as the Cdi or common-rail, I have no information available yet. 

 

General Precautions: 

Generally, every motor to be converted should be in decent running condition. If a motor isn?t doing too well on regular Diesel, chances are it will run a lot worse on vegetable oil. 
Injection pumps manufactured by Bosch have prooven to work very well with vegetable oil. Pumps made by Lucas (CAV, Rotodiesel, Delphi) are more problematic. In general it can also be said that in-line pumps are more forgiving than rotary pumps. 

Compression: 
This basically means how well your motor can build up pressure in the cylinders. It can be measured relatively easy with a meter that screws in instead of the injectors or the glowplugs. For cars and light trucks it should be at least 20 bars (290psi). If you have no way of measuring, you can assume that if the warm motor starts up at once, the compression is probably ok. 
Bad compression means not only an inefficient motor, but also that small quantities of unburnt fuel can escape from the cylinders and mix with the lubricating oil. If you?re running on regular Diesel, this is not a big problem, but vegetable oil can accumulate within the lubricating oil cycle, clog up the (sometimes very small) paths of the oil and so cause colossal damage. 
This is why in general the lubricating oil and its filters should be frequently checked and changed when using vegetable oil. Some companies also install fine oil filters (such as trabold filters, see www.trabold.de) to provide additional safety. 

Injectors:
Good injectors are necessary to assure that the fuel is properly mixed with air. They open when the necessary pressure for injection is reached and create a mist of fuel. 
Especially for the use of vegetable oil, this is very important. 
You can remove the injectors and have them tested. Be aware that some vehicles have special washers in between the injectors and the combustion chamber, which should be replaced when taking the injectors in or out. 
The machines to test injectors (basically a high pressure hand pump with a meter that shows the pressure) cost around 350 euros here and can be found in many shops that work a lot with Diesel powered vehicles. Some French experts recommend adjusting the pressure to 185 bars. (2680psi) for the use of sunfloweroil. I think that?s a lot, but a plus of 20 bars (290psi) or 30 bars (435psi) should be ok. 
Note that changing the pressure of the injectors will change the motor's timing. If the pressure is higher, the pump takes longer to build it up and the injection starts later. You can adjust the pump by changing its timing. I heard of a change of 1° in advance for 135 bars (1955psi) and 2,5° for 185 bars. (2680psi). 
The injection system is an assembly of parts that work as a whole, so changing one parameter always affects the others. 
Changing the pressure is not too hard if you have an expert work on the actual injectors and take them in and out yourself, but adjusting the timing of the pump can be quite tricky . 

 

Problems while using vegetable oil and their solutions: 

Viscosity:

The main problem with vegetable oil is that it is much thicker than Diesel fuel. Rapeseed oil at 20 °C (68 °F) is nearly twenty times as thick as Diesel. Sunfloweroil is a little thinner, but only a little. You can imagine that this will put a lot of extra stress on your injection system. 
The solution is to heat the oil. Visualize honey in the sun to get a sense for how drastically the viscosity of a substance can change with its temperature. Even raising the temperature to 50 °C (122 °F) reduces the oil's thickness by the factor three. 
At 80 °C (176°F), which is about the temperature we're aiming for, it's still more than twice as thick as Diesel, but a good injection pump can cope with that. A temperature significantly higher would put a lot of thermic stress on the pump and also cause problems for the exposed fuel lines and filters. Every motor has a different ideal temperature, but a rule of thumb is that the temperature of the motor itself (around 80 °C) will be sufficient. 

There are three different sources of heat available: 

1.) Exhaust. The tempting thing about heat from the exhaust system is that it is available right away and that there is plenty of it. But the exhaust pipes are a good bit hotter than the oil temperature we're aiming for, which is why you would have to construct a very elaborate system to reach the right temperature. I gave up on that after a few experiments, because there are more elegant ways. 

2.) Electricity: The motor's generator produces enough electricity to use some of it for preheating the fuel. This will put extra stress on the generator and reduce the power that is available after all, but since a few hundred watts are sufficient, this loss is insignificant. The advantage is that in combination with a thermometer, an electric heating device can be used to reach exactly the right temperature. 

3.) Water: The great thing about the motor's cooling water is that it has exactly the right temperature. The same thing is true for the lubricating oil, but I prefer to mess with the water cycle. Ideally a big heat exchanger would bring water and vegetable oil to exactly the same temperature, but there are limitations in size. Another advantage is that absolutely no energy is lost, since some of the motor's excess of heat is used for the fuel.

Return fuel flow:

Another potential problem is the return flow of the fuel. The injection pump always sucks the same amount of fuel from the tank, which is the absolute maximum it could possibly inject into the cylinders. In most situations, the full amount is not required, and the rest just flows back into the tank. For the use of preheated vegetable oil, this creates two problems: 

a.) A lot of extra energy is required to heat fuel which isn't even burnt right away. 
b.) The tank gradually warms up, and a tank with 60 litres of hot oil can be a hazard. 

That's why in many systems the return fuel flow is simply shorted, which means that instead of going back into the tank, the return fuel just flows into the fuel line which runs from the tank to the injection pump. . 
The problem with that is the following: 
The return fuel line is also used to bleed the fuel system. If we permanently short it, air bubbles have no way of escaping from it. To solve this, the short has to be temporarily suspended, even if it is just a few seconds while starting the motor or a few minutes to bleed the system after working on it. 

Cold start: 

Starting a cold motor is always a problem. This is worse in the winter, but even in the summer your motor is still 60 C° (140° F) colder than its ideal temperature when you fire it up. One cold start of the motor puts more stress on it than the next 100 kilometres. There are two main reasons for that: 

1. Metal extends when it's heated. So when the motor is cold, every single part is just a little bit too small and the whole assembly doesn't work together too well. 

2. Lubricating oil is very thick when it's cold. But in order to build up the thin lubricating oil film that prevents many parts from grinding each other to death, it has to be warm. 

Also, the inside wall of the cylinder takes a little while to heat up. That's why its temperature is a little lower and the fuel doesn't ignite that easily

All this is problematic already, and so it makes sense to avoid vegetable oil in this phase. As one mechanic said, the worst situation is cold vegetable oil meeting a cold motor. 

Rigging up a second tank that enables us to start the motor on regular Diesel is a good idea. It's also important to make sure that no vegetable oil remains in the injection system longer than a few hours, since it is full of living organisms and can quickly turn into something else in there. (In the large scale production of Biodiesel, an own substance is added that has no other purpose than massacring all those microorganisms in order to create a more stable fuel. But I guess that's ok, since we end up burning them anyways.) About 5 minutes is enough to rinse the system with regular Diesel. 

Some people work with 100% vegetable oil, but I don't like the idea. The least thing you can do for your motor in this case is to get the glow plugs to continue heating the prechamber for 30 or 60 seconds after the start. More pressure on the injectors is also necessary for a cold start on vegetable oil. With direct injection, it's generally not advisable. . 

If you are using a tank for vegetable oil that has previously been used for Diesel fuel, there's a chance that the vegetable oil (which acts as a solvent here) washes dirt that has been sitting inside the tank into the fuel filter and clogs it up. It's therefor advisable to carry a second filter with you and figure out how to change it and how to bleed the system afterwards. 
 
 

Winter use:

In very low temperatures even regular Diesel can get too thick to work properly. Of course this is a lot worse with vegetable oil. The easiest thing to avoid problems is to mix regular Diesel with it, the colder it is, the more. If the oil still becomes too thick, a cup of gasoline (uk: petrol) with a high octane rating poured into the tank will do the trick. 

The system I am using:

I have a two-step preheating system. From the tank the vegetable oil goes through a rather small heat exchanger and from there into the little pump that sucks the fuel out of the tanks. Right after that pump comes the electrical preheater. It is controllled with a temperature sensor that switches it off, if the vegetable oil that is circulating in the system (the return fuel line is shorted) already has the right temperature. From there the vegetable oil goes into the fuel filter and then into the injection pump. 
In the beginning the electrical heater was working permanently, so I suspected that it had trouble reaching the right temperature. So I insulated the filter and the fuel lines with foam coatings for house heating pipes and ever since then it works fine.
There are two magnetic valves. One switches over between the two tanks (right before the little fuel pump), the other opens the short in the return fuel line, but only while the starter is in use. This is enough to bleed the system a little, but when I have to remove a lot of air, for instance after changing a filter, I have to rewire it to remain open a few minutes. 

 

Specifications of parts to be built:

With the current prices of rapeseed oil and regular Diesel, I will have to drive about 15.000 kilometres to break even with the cost of the parts that I'm using now. This doesn't include my labour, and so I'm aware of the fact that in order to be really competitive, conversions would have to be cheaper. 
That's why I'm working on constructing the parts myself. Another solution would be to replace them by parts that can be easily scavenged or purchased cheaply. I'm still in the process of this, and it will keep me busy for a while. In the meantime I just describe what every single part is doing and how I think it could be built. If you have any ideas, please send me an e-mail. 

Heat exchange:

This part uses the heat of the motor's water or oil cycle to heat the vegetable oil. The ideal heat exchanger would have a large surface on the inside and small proportions on the outside. The one I'm using right now is the shape of a box, maybe 4 boxes of cigarettes in size. 
The vegetable oil has to be exposed to the heat of the water (or lubricating oil) with as much surface as possible, but of course the whole system has to be absolutely tight, since water in the fuel would be a big problem. 
For autoconstruction, the easiest thing is to work with a pipe-in-pipe design. The vegetable oil runs through a steel or copper pipe, which is fit into a larger pipe that contains the water. For ideal exchange, oil and water flow in opposed directions. The whole thing is thermically insulated with foam or similar material. 
That design is pretty straight. A better exchange could be provided with a coil which runs around the pipe with the water. There's a blueprint for that under (http://www.northwales.org.uk/bio-power/exchanger.htm). 

Electric heating device.

Basically any kind of fixture that uses 12 V DC to heat a metal cylinder which is connected to the 8 mm fuel line. The one I'm using right now has 200 Watts and is switched on and off by a relais which is connected to a temperature sensor. I'd be grateful for any ideas about suitable heating devices and also blueprints for temperature controlled switches. 

Temperature controle:

The more I experiment with various parts, the more I wish for decent temperature control. At the moment I'm working on a system which uses car oil thermometers. I welded two steel fuel lines into a steel cylinder that ends in a nut which holds the sensor. The whole thing still needs to be tested, the main problem here is to weld the parts absolutely airtight or assemble them any other way to resist a constant flow of hot vegetable oil. 

Magnetic valves: 

Any kind of device which can be used to switch over between two fuel lines and works on 12V DC. Of course manual switches are possible as well and also a lot cheaper, but less comfortable. 

Conclusion:

I chose the vegetable oil option because I think that it's more suitable for travelling. Doing one conversion allows me to use vegetable oil of multiple sources, although scouting out sources of cold pressed oil in different countries is still quite a mission. If you have any info on that, please send me an e-mail. 
I'm aware of the fact that biodiesel is probably the better option for the motor in the long run. 
But I have trouble imagining a travelling bio-diesel production that produces more than a symbolic amount for demonstration. That kind of operation seems to be better off stationary, and also combined with an own production of alcohol in order to provide full fuel autonomy. So my goal while I'm travelling is to encourage people to think about setting them up and create a tight network of individuals and groups working on the various solutions. . 

 

Materials and further information: 

French:
www.valenergol.free.fr - has produced sunflower oil for more than 5 years and is currently engaged in a legal battle with the French government for not paying fuel taxes.

www.tourne-sol.org – the group is touring with a generator running on sunfloweroil, an own oil press and many other brilliant ecological solutions.

German: 
www.fmso.de – lots of informations about running on straight vegetable oil, list of converted vehicles, newsgroup, extensive collection of links.

www.pflanzenoel-auto.de -also contains information on filtring chipfat

www.flottenversuch.de -  The Bavarian ministry for economy, traffic and technology paid for a large scale study with 60 vehicles converted to run on vegetable oil. The results being very positive, no official report has ever been produced, but the data can be seen on the website. 

www.rerorust.de - provides a list of fuel suppliers in germany. 

English: 
www.northwales.org.uk/bio-power – very extensive & well researched website on vegetable oil and biodiesel.

http://running_on_alcohol.tripod.com/ethanolfuel/id8.html – information for the autoconstruction of an alcohol fuel still. 

 

Books and texts: 

"how to make Biodiesel", article in SchNews

"from the fryer to the fuel tank", a book by Josh Tickell, publisher unknown

"Biocarburantes", by Luis Angel Agejas Dominguez, a publication of "Ministerio de agricultura, pesca y alimentacion", Secretaria general tecnica. – The Spanish government published this little booklet which gives a good overview on different oil sorts, agricultural perspectives and the technical aspects. 

 

Note: 

Feel free to forward this text to anybody who's interested in the subject. 
If you're interested in further publication, please contact me, since chances are that I will have an update version and more specific information ready by the time. 
Also, a revised introductory text that deals with the political implications and the legal and tax situation is on the way.

El Capitan Berlin, 8-2002