Cultivating crops in greenhouses within arid climates presents difficulties in managing temperature and humidity, often requiring cooling methods that consume significant amounts of energy and water. At the same time, thermal power plants rely on cooling at lower temperatures to improve their efficiency. Due to their affordability and effectiveness, evaporative coolers are commonly used for cooling, especially in areas with low humidity. However, the warm, humid air produced by this process is typically released into the atmosphere without being utilized. This study proposes an innovative approach called co-cooling thermal power, which integrates thermal power generation with greenhouse agriculture in hot, dry regions. In this system, evaporative cooling towers cool the power plant, and the resulting humid air is repurposed to cool greenhouses. A case study on Riyadh, Saudi Arabia, demonstrates positive impacts on agriculture, water, and energy use. Findings show that the proposed method boosts overall power production by 2.4%, factoring in the energy needed for seawater desalination and freshwater distribution while lowering investment costs. Co-cooling offers a sustainable solution that enhances resource efficiency and promotes a mutually beneficial relationship between thermal power generation and greenhouse farming in arid regions.