Biofuels and the biorefinery concept

Liquid fuels can be made by refining a range of biomass materials, including oil-rich and sugar-rich crops such as oil-seed rape and sugar beet, biomass that consists mainly of plant cell walls (second generation lignocellulosics), macro- and micro-alga, or material that would now be discarded as waste. This can include animal bi-products as well as waste wood and other resources. In the medium-term, plant cell (lignocellulosic) material is likely to be favoured as the feedstock for biorefineries because of its availability. The UK may make use of a number of these options because of its complex agricultural landscape. There are now a range of targets for biofuel use in the UK, although their environmental effects are disputed.The technology of refining these materials is well known. Possible outputs include biodiesel and bioethanol, both of which can be used as transport fuel. Other potential products include hydrogen, polymers and a wide range of value-added chemicals, making this technology important in a post-petrochemical world. Biorefineries could use cogeneration to produce electricity. The paper identifies a range of research and development priorities which must be met if this opportunity is to be exploited fully.