What are biofuels?
Biofuels – fuels derived from organic matter – either plant or animal – are not a new idea. The Model T Ford, first produced in 1908, was originally designed to use ethanol, while Rudolf Diesel’s demonstration engine ran on peanut oil in 19121. However, before long petroleum-based fuels, which could be produced more cheaply, took over. Now, as the price of fossil fuels is rising and the dangers of global warming are becoming ever clearer, biofuels are becoming more popular again.
What are the benefits of biofuels?
- Biofuels are a renewable resource.
- The plants grown to produce biofuels absorb the same amount of carbon dioxide as is released when the fuels are burnt. This means that their contribution to climate change is significantly lower than for fossil fuels.
What are the draw backs of biofuels?
- A lot of land is required to grow the crops used to create biofuels. For example, to fuel our existing transport needs exclusively with biofuels would require 90% of the world’s agricultural land2.
- The pressure for land to grow biofuel crops will endanger the world’s rainforests. It has been argued that the net loss in carbon absorption capacity on converting rainforest to biofuel plantation means that biofuels actually have a greater impact on global warming than fossil fuels3.
- Availability of supply in Britain is very limited, although this is likely to change in the near future as the government pushes for greater use of biofuels.
What kinds of biofuels are available?
Many different types of biofuel have been developed. The main ones are bioethanol, biodiesel, and pure plant oil. The variety of different biofuels is somewhat confusing. The following table summarises the essential points for each of the options discussed above.
|Fuel||Conventional fuel replaced||Engine modification needed||Use covered by car manufacturers’ warranties||Refuelling network in Britain|
|E5||Petrol||No||Yes||Yes, but not labelled|
|E85||Petrol||Nearly always||Not usually||Limited and localised|
|B100||Diesel||Not usually||Not usually||No|