More than half of the operable power plant cooling systems in the U.S. reuse water through a cooling tower or a cooling pond, according to the U.S. Energy Information Administration (EIA).
U.S. electric generating plants have historically used two methods to condense steam for electricity generation: once-through systems and recirculating systems. Power plants built after the 1960s began using recirculating systems more, especially with environmental standards for thermal discharge and impingement. Recently, plants have started using dry cooling systems, which use air passed over the cooling water to lower cooling water temperature instead of using water to lower the temperature.
Out of 1,655 operating cooling systems, 875, or 53 percent, reuse water through a cooling tower or a cooling pond, while 719, or 43 percent, do not. Another 56 systems are dry systems and five are hybrid, which can switch between dry and some sort of wet cooling.
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