Anaerobic digestion isn't glamorous. But, in the UK at least, it is increasingly fashionable. Just this month, in Doncaster, the first feedstock has been put inside what could be the first of a new generation of UK anaerobic digestion plants. Power is due to come out from the plant towards the end of September. Anaerobic digestion, or AD, is in vogue because it seems to meet two of the government's prime objectives. One is the worldwide search for viable renewable energy technologies. The other is a more local problem, disposal of waste in the UK, particularly of food, with landfill sites full. With AD, the two things go together. Or they will do at Doncaster and at other plants being put up across the UK. Waste food can be put into a digester, bugs get to work to release the energy inside it, and the end-result is a biogas that can be used for power, some process heat, and a residual digestate that can be used as fertiliser. But if this seems to create a happy logic of mutual benefit - a win-win - then there are some caveats. "It's not a panacea" says David Woolgar, engineering director of Biogen Greenfinch, one of the companies aiming to develop AD plants in the UK.
展开▼
