A typical nuclear reactor generates 1000;rm MW (1000;rm MJ/s) of electrical energy. In doing so, it produces 2000;rm MW of "waste heat" that must be removed from the reactor to keep it from melting down. Many reactors are sited next to large bodies of water so that they can use the water for cooling. Consider a reactor where the intake water is at 18;^circ rm C. State regulations limit the temperature of the output water to 30^circ rm C so as not to harm aquatic organisms