Question

Solar panels work because photons from the sun give their energy to electrons in the panels (photoelectric effect). At noon on a typical day in San Diego, the power of the visible radiation from the sun is about 225 Watts per square meter. If you had solar panels on your roof covering an area of 2 meters by 6 meters, and the efficiency of the panel was 13% (meaning that 13 out of every 100 photons hitting the panel sent an electron down the wire), how many electrons per second would you get

Answer 1

Answer:

The number of electrons per second received by the panel is 2.19 x 10²¹ electrons/second

Explanation:

Given;

intensity of light, I = 225 W/m²

area of the solar panel, A = 2m x 6m = 12m²

Power of photons hitting the panel = 225 W/m² x 12m² = 2700 W

Power received by the electrons in the panel = 0.13 x 2700 W = 351 W

Energy of these electrons = 351 J/s

The number of electrons per second is given by;

$= \frac{1 \ electron}{1.602*10^{-19} \ J} *\frac{351 \ J}{s} = 2.19*10^{21} \ electrons/second$

Therefore, the number of electrons per second received by the panel is 2.19 x 10²¹ electrons/second