Heat from treated waste
Stadtwerke Gießen is inviting the public to an open day at one of its thermal waste treatment and energy recovery plants.
How exactly is heat generated from waste? Visitors will be able to experience exactly that first-hand on 30 August 2026. On this day, Stadtwerke Gießen (SWG) will be opening its Thermal Waste Treatment and Energy Recovery Plant II – TREA II for short – to the public from 11 am to 5 pm. Since December 2022, the plant on Leihgesterner Weg has been producing electricity and heat from processed waste. As part of fascinating guided tours of the plant, SWG experts will explain exactly how the processes work, what happens at each stage and what steps are required. They will explain all the key details and, of course, answer any questions. In addition, visitors to the SWG stand can look forward to entertaining games. And last but not least, SWG will be providing food and drink at family-friendly prices.
Clever synergy
The TREA II operates on the basis of a sophisticated system: like its sister plant, TREA I, it primarily produces heat, which is supplied to households in the form of hot water via the SWG’s district heating network. The difference is that TREA II also generates electricity by using the steam produced during combustion to drive a steam turbine. Two combined heat and power (CHP) units also produce electricity and heat. This synergy makes TREA II particularly efficient.
The fuel used in the boiler is processed waste from commercial premises. ‘Processed’ here means: pre-sorted so that only the particularly energy-rich, highly combustible components of the waste enter the furnace. Experts therefore also refer to this as high-calorific waste. This results in a further clear advantage: “The fuel for the heating system comes from the local region, so it does not have to be transported to Gießen over long distances at great expense. This further improves the environmental footprint,” explains the expert.
The TREA II makes an important contribution to the energy transition in Giessen. Each year, it converts up to 28,000 tonnes of waste – roughly half of which consists of wood, cardboard, paper or pulp – into usable district heating. In total, the plant generates 60,000 megawatt-hours of heat and around 35,000 megawatt-hours of electricity. That is enough to supply around 8,100 flats with heat and just under 16,000 average households with electricity each year.
Just pop in
Anyone wishing to find out more about how TREA II works and about district heating is welcome to drop by during the open day. No booking is required. There is plenty of free parking available in the immediate vicinity, on the grounds of Justus Liebig University. Guided tours start every 30 to 40 minutes as required.