The Weinbergskirche church in Dresden-Trachau is now heated using wastewater heat. The refurbishment concept combines energy-related measures on the building envelope and a switch to renewable energies: 75% of the heat requirement is covered by waste heat from a nearby sewer, supported by a heat pump and a photovoltaic system. A gas condensing boiler covers the remaining demand. The historic façade has been preserved.
The costs for the efficiency measures totalled 270,000 euros (total refurbishment: 1 million euros), subsidised with 200,000 euros from EU and state funds. Despite the planned multiple uses (meetings, concerts, celebrations), CO₂ emissions are reduced by 90 %.