The nuclear power plant at which you’re the public affairs manager has a backup gas-turbine system. The backup system produces electrical energy at the rate of 360 MW, while extracting energy from natural gas at the rate of 670 MW. The local town council has raised concern over waste thermal energy dumped into the environment. Their standards state the thermal waste power must not exceed 400 MW and that all power generation must be at least 50% efficient. Does the backup turbine meet this standard?
Want to see the full answer?
Check out a sample textbook solutionChapter 18 Solutions
Essential University Physics (3rd Edition)
Additional Science Textbook Solutions
Physics: Principles with Applications
College Physics: A Strategic Approach (3rd Edition)
Essential University Physics: Volume 1 (3rd Edition)
The Cosmic Perspective Fundamentals (2nd Edition)
Introduction to Electrodynamics
The Cosmic Perspective (8th Edition)
- Water falls over a dam of height h with a mass flow rate of R, in units of kilograms per second. (a) Show that the power available from the water is P=Rgh where g is the free-fall acceleration. (b) Each hydroelectric unit at the Grand Coulee Dam takes in water at a rate of 8.50 105 kg/s from a height of 87.0 m. The power developed by the falling water is converted to electric power with an efficiency of 85.0%. How much electric power does each hydroelectric unit produce?arrow_forwardb) Energy may be stored for use during peak demand by pumping water to a high reservoir when needed. Suppose water is pumped to a lake 135 m above the turbines and at a rate of 1.35 x 10 kgs" for 10 hrs at night. ) How much energy (kWh) is needed to do this each night. i) If all this energy is released during a-14 h day, at 75% efficiency, what is the average power output? e) State three forms of environmental polution and how they can be prevented.arrow_forwardA steam power plant with a power output of 150 MW consumes coal at a rate of 60 tons/h. If the heating value of the coal is 30,000 kJ/kg, determine the overall efficiency of this plant.arrow_forward
- Iceland has both high geothermal activity, with high temperatures near the surface, and abundant cold surface water. Iceland has many power plants that take advantage of the proximity of these natural hot and cold reservoirs. One plant uses an underground source at 122°C as the hot reservoir and a nearby lake at 5°C as the cold reservoir. The plant draws 16 MW from the hot reservoir to produce 1.8 MW of electricity. How does the actual efficiency of the plant compare to the theoretical maximum efficiency?arrow_forwardThe average electricity consumption of a house in Gainesville is known to be 1,036 kWh in a month (One month = 30 days). They would like to install solar panels of 30 % efficiency to generate this electricity. Given that the average solar power density in Gainesville is 5.47 kWh/m2/day, how much surface area must the panels occupy? Calculate the result in m² but do not write the unit. Round off you E swer to a whole number (zero decimal place.)arrow_forwardWhen a certain type of coal is burned at a power plant, 22.6 ×106×106 joules per kilogram are released that is subsequently used to boil water and produce steam. The steam then does work on the turbine to produce electricity. If power is produced at a rate of 480 megawatts as 102000 kilograms of coal are burned per hour, what is the efficiency of the power plant?arrow_forward
- Many decisions are made on the basis of the payback period: the time it will take through savings to equal the capital cost of an investment. Acceptable payback times depend upon the business or philosophy one has. (For some industries, a payback period is as small as two years.) Suppose you wish to install the extra insulation in Exercise. If energy cost $1.00 per million joules and the insulation was $4.00 per square meter, then calculate the simple payback time. Take the average ΔT for the 120 day heating season to be 15.0ºC.arrow_forwardI often make tea in my microwave oven. I know that it takes two minutes to bring the temperature of a cup of water from room temperature to just about boiling: ready for the teabag. I looked up the characteristics of a microwave oven. Typically their power rating is about 1000 W, but I know that this is the power consumed from the power company, not the power delivered to the water. I looked up the efficiency of microwave ovens, and found that it is about 64%, meaning that a typical oven delivers 640 W to the water. I also looked up the frequency of the microwaves that an oven uses, and found thatf= 2,450 MHz. (a) How much energy is delivered to the water in the making of a cup of tea? (b) What is the wavelength of the microwave? (c) What is the energy of one microwave photon? (d) How many microwave photons are absorbed by the water in making a cup of tea?arrow_forwardA diesel generator supplies a small mine, not connected to a power grid, with power. The maximum output is 1000 kW. The efficiency of the generator is 85 per cent and that of the diesel engine is 40 per cent. Calculate the maximum mass of fuel consumed per hour if the calorific value of the fuel is 44MJ/kg. Calculate the minimum capacity of the fuel tank required if the density of the fuel is 0.95 kg/litre and the load factor is 0.55 over 24 hours. Fuel is only delivered once a week.arrow_forward
- 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!]arrow_forwardYou use a quantity of fuel with a total energy content of 19.02 MJ to power an engine. If the average output of the engine over 2 hours was 2.12 kW, what is the efficiency of the engine?arrow_forwardIceland has both high geothermal activity, with high temperatures near the surface, and abundant cold surface water. Iceland has many power plants that take advantage of the proximity of these natural hot and cold reservoirs. One plant uses an underground source at 122°C as the hot reservoir and a nearby lake at 5°C as the cold reservoir. The plant draws 16 MW from the hot reservoir to produce 1.8 MW of electricity. How does the actual efficiency ofthe plant compare to the theoretical maximum efficiency?arrow_forward
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPhysics for Scientists and Engineers, Technology ...PhysicsISBN:9781305116399Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning