A combined cycle power plant burns natural gas and produces 600MW and has an efficiency of 48%. Find the wholesale cost of natural gas (use the internet…) and determine the cost of the fuel burned per second for the plant to produce it rated output of 600MW. If the combined cycle power plant rejects its heat to a nearby lake with 16,000-acre feet of water, how fast in degrees/day will the temperature of the lake rise if it is assumed that the lake is insulated and cannot reject heat in any other way? How do power plant lakes get rid of heat in the real world?

4. Suppose that a nuclear power plant has an efficiency of about 0.34, and generates 1000 MW of power. It is located on the banks of a major river that is 67 m wide near the plant, approximately 3 m deep, and flows at a rate of 0.5 m/s. Suppose that the plant re-routes all of this water into the plant and dumps its waste heat evenly throughout the water, then returns the warmer water to the river. How much warmer is the river downstream of the plant compared to upstream? Water's specific heat is approximately 4184 J/kg/K, and its density is 1000 kg/m³. [Answer: The water is warmer by 4.62 K. This is a lot warmer!]

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The input power to operate a boiler comes from an electrical circuit with a voltage of 110 volts [ V ] and a resistance of 3 ohms [ Ω ]. The boiler produces 70 kilojoules of heat per minute [ k J m i n ] . What is the efficiency of the boiler, expressed as a percentage [ % ] ?