A heating system must maintain the interior of a building at TH = 20 °C when the outside temperature is TC = 2 °C. If the rate of heat transfer from the building through its walls and roof is 16.4 kW, determine the electrical power required, in kW, to heat the building using (a) electrical-resistance heating, (b) a heat pump whose coefficient of performance is 3.0, (c) a reversible heat pump operating between hot and cold reservoirs at 20 °C and 2 °C, respectively.

a)

b)

c)  

Explanation:

From the question we are told that:

Interior temperature

outside temperature is

Rate

a)

Generally electric resistance heating is the heat transfer from interior building

Therefore

b)

COP =3

Generally the equation for coefficient of performance is mathematically given by

Therefore

c)

Generally the equation for coefficient of performance is mathematically given by

Therefore

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answer:

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