The peak generation of power is on a cool clear day, when the sun is perpendicular to the solar array. Weather, seasonal changes in the angle of the sun, array soiling, roof orientation and any incidental shading may impact on the performance of the system.

Please note: the calculations are based on meteorological data for Perth, WA. Based on a tilt angle of 19 degrees, with the array facing due north under average solar conditions. Calculation does not include compensation for dirt build-up. Electrical losses or temperature losses which will affect total output, have been given a figure of 15%. All conditions can vary from site to site. The figures have been worked out using the formula: