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A New Day for Biogas: Germany Leads the Way in Europe Biogas has a long history as a renewable resource that seemed to have more potential than practicality. However, government policies that promise stable revenues for producers and more opportunities for farmers have led to a biogas boom in Germany. By Jerry W. Kram
t seems so simple. Fill a tank with some manure, stover, straw, rotten vegetables—just about any kind of biomass—cover it to keep out air and let countless trillions of methane-producing bacteria convert worthless waste into valuable fuel and fertilizer. That’s easy right? The answer is yes, but the dilemma has always been finding ways to economically use the biogas that’s been created. Biogas has a relatively low energy content. As it comes out of an anaerobic digester, biogas is only one-half to three-fourths methane. Most of the remainder is carbon dioxide and biogas often contains a significant amount of water and sulfur-containing compounds. These compounds have to be removed before biogas can be blended with natural gas and transported via pipeline. These limitations have made it difficult for biogas to become an important energy resource in industrialized countries. Europe, however, is committed to reducing carbon dioxide emissions, and is increasing its use of wind, solar and biomass technologies. Biogas is a small but rapidly expanding part of the continent’s renewable energy portfolio. Sweden, Austria and Denmark are leaders in the development of biogas, but nowhere is the potential of this industry
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24 BIOMASS MAGAZINE 6|2007