The Technical & Economic Feasibility of Energy Recovery in Water Supply Networks

Water supply is a core service on which civilised society depends. It involves considerable energy consumption and, as a result, CO2 emissions (in water treatment, pumping and monitoring) and economic costs. Treated water is most commonly supplied from a central storage reservoir by gravity throughout a catchment and this water must be supplied within satisfactory pressure bands. Where the pressure in water flow becomes too high, a Break Pressure Tank (BPT) is commonly installed in the network, whereby the pressure, kinetic and potential energy within the flow is dissipated to the atmosphere. These BPTs present an opportunity to recover energy from water supply networks by means of a hydropower turbine system, thereby improving the sustainability of the network without interfering with the water supply service. This paper presents the results of a preliminary technical and economic feasibility assessment of the energy recoverable from BPTs.