Manure’s value as a source of energy

Experts at the UK Research Council’s Rural Economy and Land Use programme claim that using manure for energy production can help farmers boost income and help the Government to hit green energy targets and cut greenhouse gas emissions.

Researchers investigated the potential for small-scale farm-based anaerobic digestion plants and found that relatively small digesters could be economically viable when fed with mixtures of animal slurries and imported wastes or energy crops, and had the potential to boost the profits of both arable and dairy farms.

Wider adoption of the technology would also help farming to become greener. Digesting the slurry produced by one dairy cow has the potential to reduce methane emissions by 25 kg, and generate power equivalent to three months’ electricity consumption for an average household,

The digestate left at the end of the process is a valuable fertiliser if spread on the land, reducing the amount of money farmers spend on artificial fertilisers.

Professor Charles Banks, from Southampton University who led the research, said: “Other European countries have forged ahead with this technology. But although the UK Government has expressed its support, this has still not led to widespread adoption of the technology on farms.

“This research has shown that there is an economic incentive for farmers, but further encouragement may be necessary, and perhaps some financial support for demonstration projects. Widespread adoption could provide multiple benefits, not just for the farmer but also for the environment.”

The issue of anaerobic digestion remains contentious for many dairy farmers, however, as their use is subject to large amounts of red tape. A farmer wishing to take manure to a neighbour’s farm for spreading can do so freely but to take it to a farm for use in a digester requires large amounts of paperwork to be completed.