NGlobal Magazin 01-2010

Energy 35 ferroconcrete fermenter. At temperatures between 35 and 38 degrees Celsius the biomass is kept snug and decomposes thanks to the work of bacteria. These bacteria produce a gas which is rich in methane, the so-called biogas. This gets used later to operate block- type thermal power stations that produce electricity and heat. Bacteria Feedcontrol Up until now the biomass was added according to a set rhythm. “Feedcontrol”, however, has sensors and computers measuring the current status of fermen- tation, thereby allowing the machine to feed in the bacteria at the precise time when these can process the substratum best. As a result, owing to the more efficient use of biomass, ten percent less of cultivated land is needed to produce the same amount of ener- gy. Looking at a 500kW-plant, annual savings of up to 20,000 euros are possible. As a final step, once the bi- omass is fermented, the remaining matter is used for the production of compost and liquid fertilizer which, in turn, boost plant growth. The cycle closes. Highlights Made in Vechta Weltec BioPower is another manufacturer of bio- gas plants that enjoy international popularity, such as in England, Finland, the U.S. and in Japan, in- deed all over the world. What makes them special is a fermenter — which is the heart of any biogas plant—made of stainless steel. For during the produc- tion of biogas, hydrogen sulphide and ammonia parti- cles are released. Stainless steel is much better suited to dealing with these aggressive chemicals than con- crete. It also has a longer lifetime. The Vechta-based company is planning to build, soon, near Magdeburg, the world’s second largest plant for the feeding in of biogas. Weltec is also scheduled to put up the first biogas plant in China that complies with German quality standards. For a good reason China counts among Weltec’s most important target markets. The Chinese government plans to equip seven percent of all rural households with biogas plants by 2020. Weltec reck- 6%of Niedersachsen’s energy requirements are being met through bioenergy. About “Renewable gas” Among renewable ener- gies, biogas has turned into a true all-rounder. Next to supplying elec- tricity and heat, biogas or biomethane also serves as fuel in gas- powered vehicles, and it can replace natural gas in industrial proc- esses. In order to go beyond local use and to feed biogas into the existing natural gas grid, biomethane needs to undergo processing. One of the first biogas processing plants in Germany is located in Ronnenberg near Han- nover. Every hour the fa- cility feeds some 300 m³ of methane biogas into the grid. On average the total annual production of 2.4 million m³ of gas covers 1,400 house- holds’ requirements for heat. The market for feeding biogas into the natural gas grid is still relatively young and has huge potential. Ger- many plans to replace six billion cubic metres of natural gas through its renewable alterna- tive by 2020. Accord- ing to estimates by the German Energy Agency, this would require 2,000 new biogas processing plants. At present there are some 30 installa- tions in Germany. Photo: KWS Saat Biogas is the only renewable energy source that is suitable for generating heat, power, gas, as well as liquid fuels. Photo: Bio Fuel 24 Also, unlike natural gas, biogas does not need 300 million years to generate but just one season’s yield of crops. Photo: KWS Saat › Niedersachsen Global www.nglobal.de