At a certain location, the solar power per unit area reaching Earth’s surface is 200 W/m2, averaged over a 24-hour day. If the average power requirement in your home is 3 kW and you can convert solar power to electric power with 10% efficiency, how large a collector area will you need to meet all your household energy requirements from solar energy? (Will a collector fit in your yard or on your roof?)
Solution 4P The average requirement of my home is = 3 kW = 3000 W But only 10% of solar power is converted to electric power. Therefore, to obtain 3000 W of power, the incident solar power on the collector has to be = 3000 W × 10 = 30000 W Given that, power is 200 W when the collector area is = 1 m 2 Power is 30000 W when the collector area is = 1 × 30000 m 2 200 2 = 150 m 2 Therefore, the required area of the collector should be 150 m .