Environmental Change Institute, Oxford University Centre for the Environment, University of Oxford, S Parks Road, Oxford, UK E-mail:
Institute for Data, Systems, and Society, Massachusetts Institute of Technology, Cambridge, MA, USA and Belfer Center for Science and International Affairs, Harvard Kennedy School, Cambridge, MA, USA.
Water Sci Technol. 2020 Dec;82(12):2745-2760. doi: 10.2166/wst.2020.507.
A large part of operating costs in urban water supply networks is usually due to energy use, mostly in the form of electricity consumption. There is growing pressure to reduce energy use to help save operational costs and reduce carbon emissions. However, in practice, reducing these costs has proved to be challenging because of the complexity of the systems. Indeed, many water utilities have concluded that they cannot practically achieve further energy savings in the operation of their water supply systems. This study shows how a hybrid linear and multi-objective optimization approach can be used to identify key energy consumption elements in a water supply system, and then evaluate the amount of investment needed to achieve significant operational gains at those points in the supply network. In application to the water supply system for the city of London, the method has shown that up to 18% savings in daily energy consumption are achievable. The optimal results are sensitive to discount rate and the financial value placed on greenhouse gas emissions. Valuation of greenhouse gas emissions is necessary to incentivise high levels of energy efficiency. The methodology can be used to inform planning and investment decisions, with specific focus on reducing energy consumption, for existing urban water supply systems.
城市供水管网的运营成本很大一部分通常是能源使用，主要以电力消耗的形式。为了节省运营成本和减少碳排放，减少能源使用的压力越来越大。然而，在实践中，由于系统的复杂性，降低这些成本被证明是具有挑战性的。事实上，许多水务公司得出的结论是，他们实际上无法在供水系统的运行中进一步节省能源。本研究展示了如何使用混合线性和多目标优化方法来确定供水系统中的关键能耗要素，然后评估在供水管网中的这些点上实现显著运营收益所需的投资金额。在应用于伦敦市的供水系统时，该方法表明，每天的能源消耗可节省高达 18%。最优结果对折扣率和对温室气体排放的财务价值敏感。评估温室气体排放对于激励高水平的能源效率是必要的。该方法可用于为现有城市供水管网提供信息，以做出规划和投资决策，重点是减少能源消耗。
