Since Wednesday 13 June, an almost 28-metre-long chimney has been towering upwards on a plot of land directly adjacent to the premises of Stadtwerke Gießen (SWG) in Lahnstraße. It is part of the new combined heat and power plant (CHP plant) that SWG technicians are currently building there. "The efficient combined heat and power plant (CHP) is expected to go into operation in September 2012 and will have a thermal output of around 2400 kilowatts (kW) and an electrical output of 1999 kW. Like three CHP plants of this size already installed in Giessen, it will feed heat into the municipal district heating network and increase the proportion of electricity that Giessen's municipal utilities produce themselves," explains project manager Jens Hanig.
Plants of a similar design have already been installed at the former US depot, at Umspannwerk Ost and in Schlachthofstraße. SWG expects to build two more CHP plants by the end of this year - in Versailler Strasse and Winchester Strasse in the Europaviertel district.
Strategy of decentralised supply
Matthias Funk, Head of Heat Supply at Stadtwerke Gießen, explains the important contribution that the six plants will make: "We are pursuing a strategy of using CHP to promote decentralised energy supply in Giessen city centre. Our well-developed district heating network offers ideal conditions for this. This is because we are increasing the amount of electricity that we generate ourselves and can make optimum use of the heat generated." Not just for heating or hot water, as the extensively renovated and newly opened SWG customer centre on the market square in Giessen demonstrates. During the summer months, an adsorption chiller converts the incoming heat into cold.
The municipal energy supplier has been pursuing the strategy of focussing on CHP for many years - and is on the right track. A change in the law a few weeks ago demonstrates the role the German government ascribes to CHP in the energy transition. It has increased the remuneration for electricity fed into the grid from new and modernised CHP plants in order to achieve the desired goal: Small power plants are to cover around 25 per cent of the electricity demand in Germany by 2020.