Digitalization and hydropower integration in water supply systems: Unlocking energy potential, efficiency, and resilience

Abstract

The Water-Energy Nexus highlights the interdependence of water and energy systems. Optimizing this nexus through digital solutions enhances water supply resilience, boosts renewable energy generation, reduces greenhouse gas emissions, and supports carbon neutrality by 2050. This study digitalizes a water supply system (WSS) of a typical rural Austrian municipality, including pipes, pumps, valves, junctions, tanks, and reservoirs. The digital WSS model, developed using EPANET simulations, identifies hydropower potential and supports the integration of digital solutions such as sensors for leakage reduction and monitoring. To structure these opportunities, a categorization approach is introduced for WSSs, divided into three sections (I – III) based on the available head along the water flow. Each section has its specific objectives and focus areas, ranging from energy generation for sale to powering monitoring devices. Hydraulic turbine types such as Pelton, Francis, Kaplan, pump-as-turbine (PAT), and emerging in-pipe turbines as well as energy harvesters are assigned accordingly. Techno-economic assessments evaluate energy recovery opportunities and cost-saving potentials from digitization, while SWOT and PESTLE analyses support strategic risk management. Results revealed that section I focus on energy sales as an additional revenue stream for the WSS, achieving a use-case-specific levelized cost of electricity (LCoE) of 103 €/MWh with a Pelton turbine. In section II, several hidden hydropower potential points were identified, including a maximum single-point potential of approx. 6.9 kW at a pressure reduction valve, yielding LCoE of 26 €/MWh with a PAT. This potential is found suitable for local supply and to increase self-sufficiency of the WSS. In section III, digitized monitoring enables earlier leakage detection, with potentially savings up to 30 % of revenue water. Digitalized WSSs are essential for optimizing both energy and water efficiency. They foster the development of smarter WSSs, enhance resilience and ensure a secure and reliable water supply.