Bio-Diesel is a fuel with attributes showing remarkable similarities to ordinary diesel but it is made out of renewable plant oils or animal fats. The oils used tend in the main to be rapeseed oil, sunflower oil, palm oil or soya bean oil.

To obtain a fuel of high quality the oils need to undergo a chemical reaction with methanol resulting in a methyl ester. An example of this is rape-methyl-ester (RME). Bio-diesel is non-toxic, contains low levels of sulphur and aromatics and is bio-degradable.

The combustion properties of diesel and bio-diesel are so similar that normal diesel engines can operate on bio-diesel with only minor technical changes.

 
No technical changes are required to engines if up to 5% bio-diesel is added to normal diesel. With a mixture greater than 5% the risk exists that the rubber used for gaskets and fuel hoses may deteriorate.

It is perhaps worthwhile mentioning that bio-diesel sold at petrol stations contains less than 5% plant/animal oil and in fact consists of mineral oil for 95%.

The following attributes are of relevance:

The difference in heating power between normal diesel and bio-diesel leads to a reduction in engine power. By treating bio-diesel with Dipetane this reduction does not take place (>35,700kj/liter).

The addition of Dipetane to bio-diesel naturally also ensures reduced fuel consumption as found with normal diesel.