Most of us understand how installing a low-flow showerhead or turning off the water while brushing our teeth makes sense for saving water. But what if buying an efficient refrigerator or installing energy-efficient lighting was just as connected to saving water? And what if those water-efficient choices also meant using less energy and causing less carbon emissions?
As it turns out, water and energy are intertwined. Producing energy uses water, and providing freshwater uses energy. Both these processes face growing limits and problems.
In most power plants, water cools the steam that spins the electricity-generating turbines. Refining transportation fuels requires water, as does producing fuels—for example, mining coal, extracting petroleum, or growing crops for biofuels. Using water in our homes and businesses requires getting it there, treating it, heating it, and more.
Because of these links between energy and water, problems for one can create problems for the other. In places where using energy requires a large share of available water, or where water resources are scarce or stressed by competing pressures (such as the needs of farmers or of local ecosystems or, increasingly in many parts of the United States, by climate change), the energy-water connection can turn into a collision—with dangerous implications for both.