6.23 A family uses 8 kW of power.
(a) Direct solar energy is incident on the horizontal surface at an average rate of 200 W per square meter. If 20% of this energy can be converted to useful electrical energy, how large an area is needed to supply 8 kW?
(b) Compare this area to that of the roof of a typical house.
6.23 A family uses 8 kW of power.
(a) Direct solar energy is incident on the horizontal surface at an average rate of 200 W per square meter. If 20% of this energy can be converted to useful electrical energy, how large an area is needed to supply 8 kW?
(b) Compare this area to that of the roof of a typical house.
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1 Answer
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6.23 Power used by the family = 8 kW = 8000 W
(a) Solar energy received = 200 W/
Percentage conversion of Solar energy to Electrical energy = 20%
If the area required is A then 0.2
A = 200 . The comparable roof size is 14.14 X 14.14 m
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