Anaerobic digester

In Europe, Northern Irish vegetable producer Gilfresh Produce will soon operate a 500kW anaerobic digestion plant, turning their vegetable waste into power in an example of the potential of this type of renewable energy for Africa.

In January, the family-run farm which includes root vegetables, salad crops and a variety of cabbage commissioned German Weltec Biopower to begin building the anaerobic digestion plant on their farm in Loughgall, Northern Ireland.

Waste to power

Anaerobic digestion plant
Irish vegetable producer turns waste into power. Pic Credit: Weltec Biopower

Gilfresh will no longer be supplying cattle farmers with their waste for feed as all sludge will be fed into the bioreactor as of July this year.

Weltec will install an underground pre-storage rank before the two 2,625 cubic metre stainless steel digesters, and a 6,000 cubic metre tank is planned for the gas-tight digestate storage.

Cattle manure, chicken litter as well as whole crop, grass and maize silage are all usable products which will be loaded into the system in addition to the vegetable waste.

Together with a 80 cubic metre solid matter dosing feeder, the Weltec system ensures efficient shredding and intensive mixing of the vegetable waste and long-fibre silage. The optimal pre-processing of the substances ensures, not only biological decomposition and efficient gas yield, but also low energy consumption of the plant, Weltec said in a company statement.

Thomas Gilpin, founder of Gilfresh, said: “The biogas plant will enable us to pursue our growth course on the one, hand and our ecological goals on the other hand."

Gilfresh will be able to generate 40% of their own power needs, reducing their carbon footprint and working towards a greener business model.

Gilfresh claims that the efficiency will increase due to the upcoming expansion of the cold storage. The surplus power is fed into the public grid, and the process heat is made use of for heating the company buildings and for the production processes.

“If other entrepreneurs follow the example of Gilfresh Produce, the United Kingdom will be able to reach the defined climate goals," says sales manager of Weltec Biopower UK Kevin Monson.