Energy-efficient water management and energy production from waste water or the waste products resulting from the treatment are the central topics of the working group. Wastewater treatment requires about 35 kilowatt hours of electricity per year per connected inhabitant.

Rising energy prices, increased cost pressure and targeted CO2 reduction make energy efficiency for wastewater treatment plant operators a major issue. Energy production from waste products such as the use of digester gas for combined heat and power plants are measures to reduce the electricity costs of wastewater treatment plants and at the same time make good use of the waste products.