As an energy-generating accompanying measure reducing operating costs in industrial plants or in micro and small hydropower plants, the use of a pump as a turbine (PaT) allows previously unnoticed potentials for energy generation to be profitably realised.
Usually, centrifugal pumps running backwards are used for power generation: When water flows backwards through a pump, the rotational direction of the impeller reverses and the pumps become turbines.
Not the legal requirements such as the EU directive ErP (Energy-related Products) for the reduction of greenhouse gases, but the saving of energy costs and the resulting competitiveness are powerful arguments for energy-efficient pump systems. Energy costs can account for up to 85 percent of life cycle costs.
The basic criteria for energy-efficient pump systems are firstly the determination of the pump's efficiency taking into account the load profile. Secondly, a design that is as close as possible to the best efficiency point and thirdly, a demand-oriented operating mode in the system by adapting the flow rate.