Biofuel
By far the majority of the fuel that is used in cars today comes from dirty, old oil. The cars of the future must be powered by electricity as much as possible, while heavy-goods transportation, shipping and aviation must use biofuels or hydrogen.
Bioethanol can be made from forest timber, or from plants such as corn or sugar. In Brazil about half of all petrol-driven transport runs on bioethanol, mostly manufactured from sugar. In Oslo, 21 buses run on bioethanol produced from wood at Borregaard. Biodiesel is manufactured from oil-rich plants such as soya or rapeseed. Second-generation technologies allow you to produce biofuels from wood.
Biofuels emit CO2 on combustion, but since the plants have absorbed an equal amount of CO2 through photosynthesis, the fuel is essentially regarded as climate-neutral. Nevertheless, because the manufacturing process itself causes emissions, the environmental effect from biofuels is normally between 40 and 80 percent of that for fossil fuels.
Work is being carried out to develop technology which will allow biofuels to be manufactured from a variety of biological material such as algae. Biogas in the form of methane is also a possibility for driving vehicles. In the Swedish city of Linköping, the city bus company runs several gas-driven buses which use methane produced by the city sewerage system. According to the authorities the project is profitable and is to be expanded.
