SUMMARY OF BIO-FUELS -
Not all Bio-Fuels are the same… We have all heard the phrase Bio-Fuel, but what exactly is a Bio-Fuel? In short it is a term used to describe a combustion-based fuel derived from sustainable organic matter. Below is a summary of the most common bio-fuels being used today. BIO-DIESEL
Probably the most popular alternative to fossil fuels at the moment. Biodiesel is manufactured from plant oil or animal fats, including waste cooking oil, by a chemical reaction called transesterification. The production process involves a number of chemical additives such as methanol and sodium hydroxide. Large quantities of water are required to purify the products and by-products such as glycerine has to be disposed of. Most engine manufacturers agree that bio-diesel can be blended with derv in small proportions (about 5% to 10%) without the need for engine modifications. Unfortunately the chemical process involved in manufacture uses up much of the Carbon Dioxide benefit of using an organic feedstock so the environmental benefits are not necessarily all that good. Indeed, if forests have been felled to grow the soya or palm oil used to make the biodiesel, the overall effect may even be worse than using fossil fuels.
BIO-ETHANOL
Bio-ethanol is a sustainable alternative to petrol (gasoline) that is derived from breaking down starch or plant sugars. The process is just like fermentation to produce alcohol. the plant matter is fermented and the alcohol, in this case ethanol, is captured by distillation. Sugar cane residues are a good source of feedstock and many plants have also been set up to use grains and maize. Unfortunately, grains and maize also form part of the staple diet for many people and for animals and the extra competition from bio-ethanol production has pushed up the price of food for many people around the world. The environmental benefits depend on the feedstock and the source of energy for fermentation and distillation. In some cases there is little, if any, carbon dioxide saving.
PURE PLANT OIL
The cleanest and purest bio-fuel of them all. Pure plant oil is a diesel substitute that does not use any chemical additives or environmentally harmful processes in its production. The oil bearing plants can be grown and processed locally avoiding the need for huge centralised production units and often saving on global transportation. What is more there is no wastage in production; all the byproducts can be used as animal feed, solid fuel or can be put back on the land as a natural fertiliser. The carbon footprint is much lower than biodiesel from comparable feedstock and because soya and palm oil are not used there is no risk that the feedstock has come from deforested areas. Verdant fuel is a high quality plant oil and is sustainable and renewable. All it requires is a simple engine modification and it can be used in most diesel-engine vehicles.
OTHER BIOFUELS
Biofuel can be produced in other ways and a lot of research is going into making bio-ethanol from plant cellulose rather than grain and maize. There are attempts to use algae to produce biodiesel and other processes that produce liquid biofuel from biomass. But all these approaches are in their early stages and it is not yet clear whether they will be competitive with existing bio-fuels.
"The latest scientific assessment has almost doubled the predicted rate of warming if no changes are made."
Donella Meadows
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