RWE Innogy establishes biogas partnership

By Ryan C. Christiansen
Web exclusive posted Feb. 17, 2009, at 2:29 p.m. CST

Germany-based RWE Innogy, the renewable energy subsidiary of the utility RWE AG, has signed a cooperative agreement with the Agricultural Association in western Germany to build and operate facilities that will produce biogas from liquid manure. The biogas will be pumped into the public natural gas pipeline and sold by RWE Innogy's sister company RWE Energy.

Residue produced during fermentation of the liquid manure to biogas will be processed to produce fertilizer and purified water, RWE Innogy said. The agricultural association will procure the liquid manure feedstock for the biogas plants and will sell the fertilizer that is produced.

Construction on the pilot-scale plant in Münsterland, Germany, is scheduled to begin in September with plans to commission it in the spring of 2010. The facility is expected to process 200,000 metric tons of manure as well as an additional 20,000 metric tons of agricultural cover crops, such as grasses and sunflowers. The plant will produce 60 gigawatt-hours of biogas and 8 gigawatt-hours of electricity, some of which will be used on site. The remaining electricity will be supplied to the national grid. The biogas produced will be enough to supply 2,500 households.

"With this plant, we are entering into new technological ground in the area of fermentation residue processing," said Olaf Heil, head of new application technology at RWE Innogy. "From a cost efficiency point of view, the fermentation residues from the liquid manure will be worth transportation as high quality fertilizers. Odor emissions will not occur because the entire process will be conducted in a closed system."

If the pilot plant is successful, RWE Innogy plans to construct additional plants in the Westphalia-Lippe region. The company also plans to establish similar biogas partnerships in other regions of Germany and throughout Europe.