The Water-Energy Trade-Off in Commercial Cooling

In the United States, there is a push to switch from traditional air conditioning systems to evaporative cooling. This change is driven by the desire to cut down on energy use and reduce the strain on the power grid. However, this shift is not as straightforward as it seems. There are other environmental factors to consider, especially water use. Evaporative cooling systems, often called EC, use less water indirectly than traditional vapor compression (VC) systems. This is because EC systems do not rely on electricity generated from water-intensive power plants. However, EC systems use a lot more water directly, about 5 to 8 times more. This is because they need water to create the cooling effect.The difference in water use is most noticeable in the hot and humid Southeastern U. S. This region has high cooling demands and a lot of moisture in the air. As a result, EC systems in this area consume even more water. So, what does this mean for the future of cooling in commercial buildings? It suggests that EC systems need to be redesigned. They should include steps to capture and reuse the water they use. This way, they can still provide cooling without wasting so much water. It is also important to note that the push for EC systems is not just about saving energy. It is also about reducing the environmental impact of cooling. By understanding the water-energy trade-off, we can make smarter choices. We can choose cooling systems that are both energy-efficient and water-wise.