A house with a south-facing roof installs photovoltaic panels on its roof to generate electricity.The photovoltaic panels have an efficiency of 10% and occupy an area with a size of 5.0 m by 8.0 m.The average solar radiation on the panels is 250 W/m²,when averaged over day/night,summer/winter,cloudy/sunny,etc.How many kilowatt-hours of electrical energy will the solar panels generate in a 30-day month?

Question

Quizplus · Accepted Answer

The area of the panels is $5.0 \, \text{m} \times 8.0 \, \text{m} = 40.0 \, \text{m}^2$. The average power received is $250 \, \text{W/m}^2$, so the total power received is $250 \, \text{W/m}^2 \times 40.0 \, \text{m}^2 = 10000 \, \text{W} = 10 \, \text{kW}$. With an efficiency of 10%, the power converted to electricity is $10 \, \text{kW} \times 0.1 = 1 \, \text{kW}$. Over a 30-day month, the energy generated is $1 \, \text{kW} \times 24 \, \text{hours/day} \times 30 \, \text{days} = 720 \, \text{kW-hr}$.

A House with a South-Facing Roof Installs Photovoltaic Panels on Its