Strawbale House

I have been thinking about making my own biodiesel for a while as I have heard and read about the process being quite simple and easily done your self. What is currently holding me back is that our current cars run on petrol instead of diesel.

Nevertheless our tractor runs on diesel so I may start with making smaller batches of biodiesel and see how I go. Next time when we turn over one of our cars we’ll go for a car with a diesel engine to make even more use of home made biodiesel.

From my reading so far, the process of making your own biodiesel from used cooking oils is not hard at all. Basically the process consists of the following steps:

1. Remove any large suspended solids by pouring the used cooking oil through a fly screen.
2. Warming up your batch of used cooking oil to about 60° Celsius.
3. Adding the correct quantities of Methanol and mixing it well into the used cooking oil.
4. Adding the correct quantities of caustic soda and mixing it in well, also.
5. Keep on gently stirring for a while and then let it rest for up to 48 hours to let the glycerine and small suspended solids settle to the bottom.
6. Your done … you can now use the oil at the top, above the glycerine and small suspended solids that have settled on the bottom, to run your diesel engine.

Of course I have left out some details in the above steps such as exact measures of the ingredients, but they vary anyway depending on the quality of the used cooking oil and will need to be determined for each batch of biodiesel you are making.

I have found that the book “Simple Biodiesel” by Robert Sharman provides an easy to understand quick introduction into making your own biodiesel. This book also contains some tips on where to get the ingredients necessary in Australia.