The usage of solar power system reduce the electricity bills and installation of the solar panel is more efficient and affordable. There are three criteria to be considered during installation of the solar panel. They are exposure to the sun, roof size and roof sloop.

Exposure to sunlight:

Solar panel must be installed in a north facing roof, this is because the exposure of sunlight throughout the day is more in north facing roof. Even the solar panels can be installed in east or west facing roof’s, but it is not much efficient like north facing roof. Installation in south facing roof is not efficient and not recommended. The panels must be completely exposed to sunlight between 9a.m and 3p.m even in the middle of winter. Letting shades of the trees and neighbouring buildings fall on the solar panel will reduce the efficiency to convert sunlight into electricity.

Size of roof

A solar panel is about 1.5 meters long and 1meter wide. They differ in power from 150 Watt to 300W. 1.5kW, 2kW, 3kW, 4kW and 5kW system will require approximately 10 square meter, 13.5 square meter, 20 square meter, 27 square meter and 34 square meter of roof space respectively.

Angle / tilt of roof

The best tilt of the solar panels depends on the quantity of electricity required (the load) and the magnitude of sunlight available, which will alter with the season. A minimum tilt of 10 degrees is recommended by the Clean Energy Council for self cleaning.