Solar Applications FAQs

How do I calculate energy from a solar panel?

The simplest way to obtain an estimate of the energy output from a solar panel array is to search the internet for online guides, in the form of maps, tables or graphs. One such example is the Consumer Guide produced by the Clean Energy Council.

To derive a more accurate estimate of the energy yield it is necessary to have information about a number of parameters, including the following:

• Amount of direct beam and diffuse solar exposure at the location, preferably for at least hourly intervals;
• Tilt and azimuth (direction from north) angles of the panels;
• Latitude of the location where the panels are installed;
• Time of year if monthly information is required;
• Potential shading by nearby obstructions;
• Efficiency of the solar panels in converting energy from the sun to electrical energy.

The energy will differ from year to year due to variability in the amount of solar energy available; for example, with changes in cloudiness from El Niño to La Niña years.