Abstract For combined-cycle power plants, the two most dominant steam condenser cooling options are the wet-cooling tower and the air-cooled (dry) systems. The wet cooling system is commonly installed on plants located in areas with available water sources, while the dry system is typically preferred in areas where water is scarce. However, owing to the increasing regulations on water conservation, water usage costs and improvements on cooling system designs, a new approach is required for the optimal selection of plant cooling systems, incorporating site climatic conditions, amongst other considerations. This study presents a comparative techno-economic analysis of a steam turbine cycle with wet- and dry- cooling systems for five typical tropical locations in Nigeria with different climatic conditions and water usage costs. The results show that in the hot (ambient temperatures > 33 °C) and dry regions (relative humidity ≤ 31 °C) and high relative humidity values ( ≥ 76%), the performance and cost implications of the plant with dry cooling was more favourable due to lower system sizes and costs requirements. Parametric investigations revealed that high ambient temperature increased the size and costs requirements of air-cooled systems while relative humidity significantly influenced the total power consumption of water-cooled systems.

中文翻译：

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不同气候带联合循环电厂干湿冷却系统技术经济比较

摘要 对于联合循环发电厂，两种最主要的蒸汽冷凝器冷却方式是湿式冷却塔和风冷（干式）系统。湿式冷却系统通常安装在位于有可用水源地区的工厂，而干式冷却系统通常安装在缺水地区。然而，由于节水、用水成本和冷却系统设计改进方面的法规不断增加，需要一种新方法来优化选择工厂冷却系统，并结合现场气候条件等考虑因素。本研究对具有不同气候条件和用水成本的尼日利亚五个典型热带地区的带有湿式和干式冷却系统的汽轮机循环进行了技术经济比较分析。结果表明，在炎热（环境温度 > 33 °C）和干燥地区（相对湿度 ≤ 31 °C）和高相对湿度值（ ≥ 76%），采用干冷方式的电厂对性能和成本的影响更大。由于较低的系统尺寸和成本要求而有利。参数调查显示，高环境温度增加了风冷系统的尺寸和成本要求，而相对湿度显着影响了水冷系统的总功耗。