Abstract
Biomass is the only renewable carbon source and can therefore be used for production of fuels and chemicals which are made from oil and natural gas today. Biofuels seem to be a promising alternative for today's fossil fuels since they can substitute more or less directly fossil fuels in the existing energy supply infrastructure. Intermittent renewables such as wind and solar energy are more challenging to the ways we distribute and consume energy, especially in the transport sector. The production of first generation biofuels (bioethanol, biodiesel) employs specially cultivated, often food crops. The production technologies for these biofuels are well established. However, first generation biofuels have several issues, as competition with food production, low fuel per hectare yield and lower CO2-saving potential compared to second generation biofuels. Second generation technologies are based on lignocellulosic feeds for mostly ethanol and diesel production. The production processes here are more complex, costly and they are not commercially available yet. Due to the climate in Norway, crops for first generation biofuels cannot be cultivated in large scale. However, on a small scale, first generation biofuels can also be sustainable, especially if they use waste as feedstock (e.g. biodiesel from fishery wastes or waste cooking oil).Feedstock for second generation biofuels production especially timber is a huge resource in Norway. It is estimated that there is 20 TWh wood accessible which can be used for biofuel/bioenergy production. Second generations (synthetic) biodiesel is a fuel that is chemically alike fossil diesel, but cleaner due to the production technology. Synthetic fuels are the only fuels that can substitute fossil kerosene in the aeronautical industry.