Peer foresees possibilities of gas from slurry

The Defra vision of a network of farm digesters, producing gas from manure, straw and surplus crops, could be saved, according to the chairman of the Anaerobic Digestion and Biogas Association, Lord Redesdale.

A conference at Reaseheath College at Nantwich, Cheshire, heard confirmation of the Yorkshire Post's recent report that the Department of Energy and Climate Change (Decc) had set the price for electricity produced from digesters at too low a level.

But Lord Redesdale, Rupert Mitford, a Northumberland peer and a Liberal Democrat spokesman on environmental matters, said the long-term prospects were still good, if the emphasis switched to the value of the gas as gas rather than as fuel for small-scale electricity generation. He believed Decc wanted to make up for its mistakes by encouraging this shift of emphasis.

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He said: "Historically, biogas has not been important because we have had North Sea gas. Although anaerobic digestion is used widely in Germany and Denmark, in the UK it is currently seen as a novel technology by financiers.

"They do see biogas as profitable but current financial incentives are influencing the industry to generate electricity rather than gas. For many businesses this is a great thing and it works in certain areas, but the size of the feedstock streams needed will limit the number of plants.

"The Government is very interested in subsidising biogas production. The trouble is that you have different departments coming up with different targets."

He said the Decc had raised doubts about whether biogas plants would continue to earn double allowances of Renewable Obligation Certificates (ROCs) – which fossil fuel consumers have to buy. The obvious alternative to ROCs is to sell electricity into the national electricity grid at a fixed price, set by the Decc in its recent Feed-in Tariff. And that tariff had turned out to be "not helpful", said Lord Redesdale.

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But the Renewable Heat Incentive, still under discussion for launch in a year's time, might make it profitable to sell into the national gas grid instead.

He said: "Depending on the mapping of the gas grid, there is potential for all farms in a particular area to come together and for biogas from slurry tanks to be carried by pipeline to a centralised scrubbing station where the gas is purified before being pumped into the gas grid."

He said the proposed subsidy for gas into the grid had been tentatively put at 4p a therm. He believed the Decc recognised its Feed-in Tariff for electricity was "a disaster" and would raise the offer on gas to make up for it – possibly to 8p or 10p, but even 5p or 6p would be interesting.

He said NVZ regulations were going to require a lot more new slurry pits and there was potential for turning them into revenue earners.

Reaseheath College principal Meredydd David said the time was still right to be looking at anaerobic digestion as a farm technology.