A typical electric water heater has an efficiency of 95 percent and costs $350 a year to operate at a unit cost of electricity of $0.11/kWh. A typical heat pump-powered water heater has a COP of 3.3 but costs about $800 more to install. Determine how many years it will take for the heat pump water heater to pay for its cost differential from the energy it saves.

Q: a) A heat engine takes 325 kJ of heat from a 1000 K energy reservoir and also 125 kJ of waste heat…

A:

Q: During the power stroke of a non-flow energy system, the internal energy of the working fluid is…

A: Please refer next page for the answer.

Q: Consider a heat engine operating between a high thermal reservoir at 500oC  and a low thermal…

A: GivenT1=500oC=773KT2=10oC=283KW=325kWQr=200kW

Q: A steam power plant receives heat from a furnace at a rate of 250 kJ/h. Heat losses to the…

A:

Q: Replacing incandescent lights with energy-efficient fluorescent lights can reduce the lighting…

A: Given data

Q: A heat pump operating based on the Carnot cycle receives heat from a reservoir at 278K and the heat…

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Q: An inventor claims to have developed a heat engine that receives 700 kJ of heat from a source at 500…

A: The maximum efficiency of an engine is the Carnot efficiency. And it is a function of the…

Q: 1. What is the difference between Carnot efficiency and Actual efficiency? 2. What processes occur…

A: (1)Carnot Efficiency is the efficiency of heat engine with maximum heat utilization.  Actual…

Q: A 1000 MW steam power plant, which is cooled by a river, has a thermal efficiency of 50 percent.…

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Q: A river flows to a lake at a rate of 120 m/s. The river is located at an elevation of 100 m above…

A: Given data: Volumetric flow rate of river into the lake, Q=120 m3/s. River is located at a elevation…

Q: . A geothermal-based trigeneration plant produces 2.5 MW of electricity, 1.8 MW of process heat, and…

A: To determine the utilisation factor for the given geothermal plant.

Q: A heat engine operates between a source at 477°C and a sink at 25°C. If heat is supplied to the heat…

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Q: How do heat transfer and energy transformation affect heat engines in electricity production?

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Q: Does a power plant that has a higher thermal efficiency necessarily have a higher second-law…

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Q: A heat engine that receives heat from a furnace at 1200°C and rejects waste heat to a river at 20°C…

A: Given data TH=1200 °c=1473 KTo=20 °c=293 Kηth=0.4

Q: A dam with a hydraulic turbine–generator located 40 m below the water surface has a rate of 4600…

A: Given that: Elevation = 40 m Mass flow rate = 4600 kg/s Electric power output = 1400 kW Generator…

Q: A refrigerator is used to keep the cold space at 5 °C by rejecting 8 kJ/s of heat by the condenser…

A: given: The temperature of the cold space, TL = 273+5 = 278 K The temperature of the outdoor air, TH=…

Q: A house loses heat at a rate of 5400 kJ/h per °C difference between the indoors and outdoors. If a…

A: Given data:-Rate of heat loss, qr=5400kJ/h-°CLet Lower temperature be THiger temperature,…

Q: A 160 MW power plant consumes fuel at a rate of 60 tons/h. if the chemical energy released by the…

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Q: A refrigerator has a second-law efficiency of 28 percent, and heat is removed from the refrigerated…

A: Given Data: Efficiency of refrigerator is η=0.28. Heat removed QL=800 Btu/min. Lower temperature is…

Q: A 2350m conveyor transports 540t/hour of ore through a vertical lift of 240m, consuming 1150kW at…

A:

Q: What are the energy types in a closed and open system?

A: Given:  Closed and open system  Energy types in closed and open system.

Q: What is a second law efficiency? How does it differ from a first law efficiency?

A: As per the guidelines, 1st question is answered.

Q: 1)Can the combined turbine-generator efficiency be greater than either the turbine efficiency or the…

A: 1. The combined turbine-generator efficiency  cannot be greater than either the turbine efficiency…

Q: Waternearthesurfaceofatropicaloceanhasatemperatureof25°C, while water 700 m beneath the surface has…

A: Let, Th be the surface high temperature of ocean. Ts be the temperature 700m beneath the surface.…

Q: The net work output of this power plant is simply the difference between the total work output of…

A: The work-producing device that best fits into the definition of a heat engine is the steam power…

Q: A Carnot heat engine operates between a source at 1000 K and a sink at 300 K. If the heat engine is…

A: Given: The temperature of the source is TH=1000 K. The temperature of the sink is TL=300 K. The rate…

Q: A/A heat pump is used to meet the heating requirements of a house and maintain it at 20 C°. On a day…

A: Given Data A heat pump is maintaining a house at 20oC. TH=20+273=293 K The outdoor temperature…

Q: How does a geothermal power plant generate electricity? Explain on the basis of heat transfer and…

A: Given: Explain a geothermal power plant on the basis of energy transformation to generate…

Q: A heat engine operates between two reservoirs at 8000 C and 200 C. One-half of the work output of…

A: Consider the diagram shown below for the given system.

Q: A steam power plant receives heat from a furnace at a rate of 280 GJ/h. Heat losses to the…

A: Given: The rate of heat receives by the steam power plant is Q1=280 GJ/h. The rate of heat losses to…

Q: What is the difference between refrigerators and heat pumps? From their mechanics and theory

A: The heat pump and refrigerator can be described as: Refrigerator: The refrigerator is a device that…

Q: Determine the maximum possible thermal efficiency of the power plant, and the maximum power output

A: Given : TH=80°C=80+273=353°K            TL=30°C=30+273=303°K           Qs=1 KJ/s

Q: Determine the minimum work per unit of heat transfer from the source reservoir that is required to…

A: To find  The minimum work required to drive a heat pump W. Given  The temperature of the sinkTh is…

Q: Calculate the net work output of a heat engine following path ABCDA in the figure below, where  V1…

A: Divide the curve into two triangles. Now the net work output of a heat engine is equal to the sum…

Q: [1/5] A refrigerator is removing heat from a cold medium at 3°C at a rate of 7200 kJ/h and rejecting…

A:

Q: Solar energy stored in large bodies of water, called solar ponds, is being used to generate…

A: Given Data: The efficiency of the solar power plant is, η=3%=0.03. The net power output of the power…

Q: It is claimed that the efficiency of a completely reversible heat engine can be doubled by doubling…

A: Take a reversible heat engine that works within the temperature limits of TH and TL where TH  is the…

Q: Power output of an hydro electric power station is equal to

A: power plant is expressed by its maximum output power. These are large quantities so rating is given…

Q: A heat pump is absorbing heat from the cold outdoors at 5°C and supplying heat to a house at 25°C at…

A: Given data as per the question Outdoor temperature = 5°C House inside temperature =25°C  Rate of…

Q: A refrigerator is removing .25 heat from a cold medium at 3°C at a rate of 7200 kJ/h and rejecting…

A:

Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.