COMMENT: Why has anaerobic digestion (AD) not taken off as a ‘green energy’ technology in the Republic of Ireland?
Some months ago AgriLand visited the Westfalia region of Germany. As part of the trip, we had the opportunity of visiting an agricultural college, which is home to dairy, beef and pig herds.
One of the most striking features of the campus was the use of anaerobic digestion as an integral part of the college’s waste management and heating systems. Significantly, the unit was set up to use a wide range of feedstocks, including slurry, farmyard manure and maize silage. We were very impressed with the fact that there was absolutely no smell whatsoever emanating from the digestor.
What’s more it was situated within 20 yards of a main road. However, I doubt if passing motorists had any idea about what they were passing given the total lack of noise emanating from the combined heat and power unit that was attached to the digestion system. Waste in: hot water and green electricity out. It’s a pretty neat trick!
It was made clear that German livestock producers – of a certain size – now regard digestion as a ‘must use’ technology as they strive to improve the overall efficiency of their farms. It also struck us that Ireland must start to think about making optimum use of our animal wastes. And in this regard anaerobic digestion must surely have a role to play.
Let’s be honest – digestion is a proven technology. Systems are now operating in countries throughout Europe and beyond. The issue is one of cost benefit. I have no idea what price German farmers can get for the green electricity they produce courtesy of their digestion systems. But it must be sufficiently attractive to allow them undertake the capital investment required.
As far as AgriLand is aware, digestion does not reduce the fertiliser value of slurry or farmyard manure. All it does is harness a proportion of the energy contained within these materials. Ireland is crying out for the development of alternative energy sources. However, the fact is that anaerobic digestion is already making a significant contribution to the green energy economy of many European countries. So, why should we not follow suit?