Operation optimisation of micro pumped storage for decarbonisation of water and electricity distribution network in urban areas

• Taller buildings improve MPS energy arbitrage without raising operational emissions. • MPS in NPWS mode cuts water use and payback period, outperforming ES mode. • Monthly MPS optimisation reduces CO 2 emissions but slightly lowers revenue. • Optimal scheduling under NPWS mode aids urban water distribution decarbonisation. The rapid growth in renewable energy generation has heightened the need for enhanced energy storage capacity. Micro Pumped Storage (MPS) offers a dual-function alternative to conventional batteries by integrating energy storage with non-potable water supply (NPWS) in high-rise buildings. This study hypothesises that jointly optimising MPS operation for emissions and water reuse can improve both environmental and economic performance. A multi-objective genetic algorithm (GA) is developed to optimise monthly scheduling under time-varying electricity prices and emission factors, incorporating penalty-based constraints to ensure water supply reliability. Our findings indicate that optimising MPS schedule can reduce operational emissions, with reductions of 4% to 25% in ES mode, and 25% to 43% in NPWS mode. Additionally, the NPWS mode reduces potable water consumption by up to 3,000 m³ annually, which translates to saving 54 MWh of energy and 44 tonnes of CO 2 within Melbourne’s water distribution network. These environmental and economic benefits contribute to a reduction in the payback period of MPS installations by up to 20 years, particularly in NPWS mode. Compared to equivalent-capacity lithium-ion batteries, MPS systems offer shorter payback periods and additional sustainability benefits. Furthermore, MPS provides a viable pathway to secure sustainability certification such as Green Star, and support urban decarbonisation through integrated water-energy optimisation.. Practical challenges, however, must be addressed for wider adoption.