Problem
We want install a PV system in a house of 3,000 ft2, single-story gable roofed house that has a total of six-tons air conditioner and receives direct sun on the roof until the afternoon when trees partially block the sun. Assume each day the house receives an average of 15 MJ of external heat load to be removed, with a peak heat load of 18 kW that occurs between 5 and 6:30 pm. The PV system that has panels with nominal 20% efficiency (electric power output/incident solar). Assuming an average solar insolation of 700 W/m2, estimate the size of the solar panels required to completely remove the house from the grid. What considerations must be account for? Does the roof have enough area to meet the power needs?