Geographic, Technologic, And Economic Analysis of Using Reclaimed Water for Thermoelectric Power Plant Cooling

Use of reclaimed watermunicipal wastewater treatment plant effluentin nonpotable applications can be a sustainable and efficient water management strategy. One such nonpotable application is at thermoelectric power plants since these facilities require cooling, often using large volumes of freshwater. To evaluate the geographic, technologic, and economic feasibility of using reclaimed water to cool thermoelectric power plants, we developed a spatially resolved model of existing power plants. Our model integrates data on power plant and municipal wastewater treatment plant operations into a combined geographic information systems and optimization approach to evaluate the feasibility of cooling system retrofits. We applied this broadly applicable methodology to 125 power plants in Texas as a test case. Results show that sufficient reclaimed water resources exist within 25 miles of 92 power plants (representing 61% of capacity and 50% of generation in our sample), with most of these facilities meeting both short-term and long-term water conservation cost goals. This retrofit analysis indicates that reclaimed water could be a suitable cooling water source for thermoelectric power plants, thereby mitigating some of the freshwater impacts of electricity generation.将再生水（reclaimed water）——即市政污水处理厂出水——应用于非饮用水用途，是一项可持续且高效的水资源管理策略。此类非饮用水应用的典型场景之一为热电厂（thermoelectric power plants），这类设施的冷却环节通常需要消耗大量淡水。为评估使用再生水为热电厂提供冷却用水的地理、技术与经济可行性，我们针对现有热电厂构建了空间解析模型（spatially resolved model）。本模型将热电厂与市政污水处理厂的运行数据整合至融合地理信息系统（Geographic Information Systems, GIS）与优化算法的分析框架中，以此评估冷却系统改造（cooling system retrofits）的可行性。我们将这套通用性较强的分析方法应用至德克萨斯州的125座热电厂作为测试案例，研究结果显示，92座热电厂周边25英里范围内均存在充足的再生水资源，覆盖本样本中61%的装机容量与50%的发电量，且其中大多数设施可同时满足短期与长期的节水成本目标。本次冷却系统改造分析表明，再生水可作为热电厂的适宜冷却水源，从而缓解发电环节对淡水的部分消耗压力。