Author(s): Matthias Kramer; Silke Wieprecht
Keywords: No Keywords
Abstract: Small hydropower turbines have been utilized for energy recovery in water supply systems for a number of years. Commonly implemented for this purpose are centrifugal pumps in turbine operation, referred to as pumps as turbines (PAT). Due to the wide field of potential applications new requirements have arisen. The turbine has to handle both demanding and specific hydraulic conditions as well as allowing for configuration in limited space. To study the implementation of PATs in the German water sector, the German Technical and Scientific Association for Gas and Water (DVGW) has created the research project titled: “Implementation studies of small turbines in water supply systems” . The goal of the project is to improve the implementation of small turbines in transfer chambers over different pressure ranges of the water distribution systems investigated. The Department of Hydraulic Engineering and Water Resources Management (LWW) at the University of Stuttgart is the research institution leading the investigation group in cooperation with three large regional water system operators: the Bodenseewasserversorgung (BWV), the Landeswasserversorgung (LW) and En BW. The effect of turbine operation on the volumetric flow measurement carried out by water flow meters when a turbine is installed upstream of the water meter is also of interest. A market analysis has produced three suitable types of energy converters: section-type pumps in turbine operation, heating circulation pumps in turbine operation, and Counter Pressure Pelton-Turbines (GDPT). In the Hydraulic Laboratory of the LWW a turbine test bench was constructed. To cover a large range of applications, three different pipes with varying diameters from DN 50 to DN 200 are set up. For each energy converter, turbine operation characteristics under different mounting conditions are recorded. These mounting conditions reflect the real installation situation in the transfer shafts.