- Biofuels are fuels made from plant or animal waste. Any plant material that is burned is a biofuel. They are alternatives to fossil fuels – but the best thing about them is that they are renewable fuels.
- Ethanol is a biofuel made using sugar cane or sugar beet. It can be mixed with petrol for use in car engines. Using ethanol helps to reduce the demand for petrol, and so conserves crude oil supplies.
Biodiesel is made from vegetable oils like rapeseed oil and used cooking oil from restaurants.
Ordinary diesel engines can run on biodiesel or on a mixture of biodiesel and normal diesel oil.
- Using biofuels may also help to reduce the overall amount of carbon dioxide that human activity puts into the atmosphere.
- When plants photosynthesise, they use carbon dioxide from the air. When a biofuel burns, it releases carbon dioxide back into the atmosphere. If the burning fuel emits the same amount of carbon dioxide as the plants absorbed, it is carbon neutral.
However, energy is needed to make fertilisers to help the plants to grow, to harvest the
crops and to make the biofuel.
- At the moment this energy comes from fossil fuels, so burning biofuels can add carbon dioxide to the atmosphere overall
- Another disadvantage is that growing crops to make into biofuels reduces the amount of land that can be used to grow food