If you are new to the topic, biodiesel is an alternative energy fuel which is generally manufactured from plant or vegetable oils, and occasionally animal fat. Biofuel can be made from both used and unused sources of oil, such as new cooking oil, or vegetable oil left-over from the deep fat fryer.
It is important to remember that biodiesel can only be used in diesel engines and not petrol engines. Biodiesel can be blended into regular diesel in any amount, such as 20% biodiesel/80% diesel (B20), or used pure 100% (B100, or ‘neat’).
Biodiesel is most commonly made by mixing plant oils with sodium hydroxide, and methanol. This splits up the fat molecules in the oil leaving a less-viscous biodiesel and one waste product which is called glycerol.
Many people ask whether their car needs to be converted to run on biodiesel. The simple answer is no, so all you need to do is drive to the nearest biodiesel pump, put the spout in the side of the car, and pump the biodiesel into your fuel tank (provided it’s a diesel). You can use biodiesel in almost any diesel engine without modification. In fact, if you own a diesel vehicle you can probably fill it up today with 100% biodiesel (B100) and should experience no problems whatsoever. Having said that, you should check that you will not void your warranty by using biofuel as an alternative energy source.
Biodiesel and diesel fuel are similar in chemical structure and have very similar properties, so they burn similarly in diesel engines however biodiesel has some specific advantages over ordinary diesel fuel. Biodiesel adds lubricity to the fuel, reducing engine and fuel pump wear and reportedly extending engine life. Biodiesel is also a good solvent and will clean out diesel fuel residue left in the fuel tank and fuel lines.
Biodiesel contains about 9% less energy per litre than petroleum diesel. For someone using B20, this means approximately a 2% loss in power, torque, and fuel efficiency. As an alternative energy, biodiesel has also been used extensively in heavy-machinery and agricultural equipment, with no noticeable difference.
B100 users may notice a slight drop in fuel mileage based on the small difference in energy content, but torque and power are usually comparable.
Depending on the environment in which biodiesel is being used, it may be necessary to blend biodiesel with petroleum diesel. This is because biodiesel starts to freeze at higher temperatures when compared to regular diesel, and therefore it’s important to blend biodiesel with diesel fuel in the winter (depending on your climate). Here are the biodiesel cold-weather guidelines:
If you end up using the wrong blend, or get caught in a cold snap, it isn’t the end of the world. Your engine will shut off when the fuel filter clogs from partially gelled biodiesel. This doesn’t cause any permanent damage, but you will have to wait for a sunny day or apply some serious heat to get things running again. The usual way to get around this is to heat the fuel system.