What to do with 12,000 tonnes of pig poo? That’s the question farmers James Hart and Jeremy Iles found themselves asking two years ago when contemplating how best to supplement their dwindling incomes.
Thanks to the buying power of the major supermarkets, pig farming is no longer as profitable as it once was, and Mr Hart in particular was looking at ways to make the most of the resources at his disposal.
The solution they came up with was beautifully simple; turn the huge amount of pig faeces generated on the farm – not to mention cow dung and chicken droppings – into hard cash…
Glebe Farm near the sleepy village of Hatherop in Gloucestershire is an unlikely place to stumble across a state-of-the-art, million pound biogas station of which there are just a handful in the UK.
The plant itself is wholly unremarkable to look at, but what goes on inside could help to revolutionise not just this farm, but hundreds of others just like it across the country.
In fact, the technology is proven and, given the government subsidies available, profitable. It’s just that, like with most renewable energies, the UK has been painstakingly slow on the uptake. In Germany, for example, there are thousands of similar plants.
In essence, vast quantities of animal waste are mixed with lots of grass in a cylindrical tower – “basically a 3,000 tonne cow’s stomach,” says Mr Hart.
Bacteria then break down the mixture, producing methane, which is siphoned off, cleaned and filtered.
This gas is then used to power what is effectively a £200,000 Mercedes truck engine, which in turn powers a generator, electricity from which is fed into the National Grid.
A by-product of the process is large quantities of fertiliser that remain in the tower once the bacteria have worked their magic.
The heat generated by the process is also captured and used for central heating at the farm house. It is, then, in renewable-energy speak, an efficient ‘closed-loop’ system.
No doubt the inevitable whine will burp from the blowhole of conservative critics – exclaiming over there being any sort of subsidy for new technology. Conveniently forgetting all the established “old” technology has always managed a government subsidy for the good of the people.
RTFA for lots of interesting detail.