August 2002 - Nr. 8
Going Geothermal in Germany
TWIG - The entire town of Simbach am Inn (Bavaria) is under construction. Scarcely a thoroughfare is passable. What is behind - or, more accurately - beneath this upheaval is a pioneering project to tap into one of the cheapest and most environmentally friendly resources on earth: geothermal energy. As the Frankfurter Allgemeine Zeitung recently reported, the Simbach project, which is being jointly developed with the neighbouring Austrian town of Braunau, is the first European cross-border geothermal district heating network, a joint effort of the European Union, the state of Bavaria and the government of upper Austria.
Scientists first voiced their suspicions that the earth below Simbach contains significant geothermal sources in the early 1970s. Four years ago, drilling began and quickly proved the experts right. Some 2,000 meters below the little town lies a vast reserve of water naturally heated to 90° Celsius (194° Fahrenheit), just a few degrees shy of the boiling point.
The basic principal is this: The hot water is extracted from deep thermal reserves and pumped to the surface. It is then conducted through a heat-exchanging device, which heats a transporting liquid that is then conducted along a district heating grid roughly 9 miles in length connected with each house in the district. Afterward, the cooled water is flushed back to a point approximately 1.5 miles from the drilling site and pumped down into the earth, where the water is naturally reheated. This keeps both the supply of hot water and the water pressure under and above ground constant. On extraordinarily cold days, an additional peak load boiler, which burns fossil fuels, can be used.
The costs of geothermal energy vary from household to household. The newer the heating system, the lower the cost of basic monthly charges. The fees collected will by and large go to the German-Austrian border area and serve as a basis for new investments. It is hoped that new jobs will also be created and new businesses lured to the area. In the future, not just residential homes, but businesses, hospitals and schools will be connected to the inexpensive geothermal heating system.
Already, more than 250 houses and a few commercial operations are connected. Although demand is growing, it is not yet technically or economically viable to connect all households, since a wide-ranging network would necessitate long branch extensions that would stretch the transporting liquid’s heating capacity as well as the project’s budget. Total costs, to be born by the two regions and the EU, are estimated at 21 million euros.
The environmental dividends remain the greatest reward for such an investment. Geothermal energy is in seemingly limitless supply, entails no degradation or contamination of the surrounding landscape and in the Simbach-Braunau area alone will prevent an estimated 8,500 tons of carbon dioxide, 6.8 tons of sulfur dioxide and 6.3 tons of nitrogen oxide from being released into the environment each year.
