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A 32%-efficient electric power plant produces 900MWof electric power and discharges waste heat into 20C ocean water. Suppose the waste heat could be used to heat homes during the winter instead of being discharged into the ocean. A typical American house requires an average of 20kW for heating. How many homes could be heated with the waste heat of this one power plant?

Short Answer

Expert verified

The waste heat of this one power plant will heat up95625homes.

Step by step solution

01

Definition of efficiency of electric power plant 

Efficiency of a power plant is the ratio of output power to input power . To calculate waste , output power will be subtracted from input power .

efficiency =outputpowerinputpower

wasted power = input power - output power .

02

Calculation of wasted power 

The 900MWof electric power generated represents 32%of the energy taken from the fuel.

input power = 900MW.32=2812.5MW.

Waste = input power - output power = 2812.5 MW - 900 MW

= 1912.5 MW.

This is distributed equally to each home , with each home taking a share of 20 kW .

Then their maximal number n would be such that

n=PcPh

Therefore, substituting numerically the expression for the cooling power and the power used by each home, we have

n=1912.5MW20kW=1912.510620103=95625

03

Expression of cooling power

With power used by each home ,we can have 95625homes

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