Greenhouse Emissions
The plant grows, consuming carbon dioxide and water. Energy absorbed from the sun allows the plant to produce long chains of carbon atoms, which are combined with hydrogen and oxygen. The result is vegetable oil. When burned, energy is released and carbon dioxide and water are formed. The carbon dioxide forms part of the natural carbon cycle and thus does not contribute to greenhouse gas emissions.
Current farming practices rely on the use of fossil fuels and hence the production of vegetable oils is not itself carbon-neutral. In addition, methanol, which is one of the components used in the biodiesel reaction, can be produced from Biomass but is typically produced from natural gas.
In May 1998, the US Department of Energy (DOE) and US Department of Agriculture (USDA) published the results of the 'Biodiesel Lifecycle Inventory Study' which analyzed this issue in detail. It concluded that for soybean oil in the US, the overall lifecycle emissions of carbon dioxide from biodiesel are 78% lower than the overall carbon dioxide emissions from petroleum diesel. The study stated that "the reduction is a direct result of carbon recycling in soybean plants". The same basic conclusion applies to other oil feedstock crops.
In time, we hope to develop sources and techniques which can further reduce the emissions associated with the use of our biodiesel products. The carbon footprint of biodiesel use can be further reduced by encouraging the use of renewable fuels in production, sourcing other feedstock from renewable sources, and recycling used oil.
Engine Wear
Biodiesel is a better lubricant than petro-diesel, prolonging the life of the injector system. However, it is known that, over time, straight biodiesel can degrade neoprene rubber seals in the fuel system. Since this also causes problems when used with ultra-low sulphur diesel, many modern engines avoid the use of this type of rubber. If in doubt, please do your own research and let us know what you find out. We will keep an up-to-date list of key information about diesel vehicles on this site. There are also many internet sites and forums available to help with this process.
Cost
The cost of biodiesel is not completely independent from the price of petroleum. Vegetable oil prices depend on the fuel costs incurred in farming, production and transport of the oil. However, the cost-dependence of petro-diesel on petroleum is much higher and less flexible. We anticipate that biodiesel will significantly improve its cost position relative to petro-diesel into the future.