How much solar power do systems generate? What affects the output?

Please try our solar calculator for your area to see how much electricity different sized solar systems generate. A number of factors can affect how much energy your solar system will generate. We have separated these into primary effects (the things that make a big difference) and secondary effects (the things that make a smaller difference). They include the following:
Primary effects on generation
- Rating of the panel i.e. its efficiency - a LG NeON2 315W panel will generate more electricity than a standard 285W Mono X2 panel and more again than an industry standard 260W panel
- Location of panels - a northern roof panel will generate much more electricity than a panel on a southern roof. As a matter of fact southern roofs are not suited for solar panel installation in Australia
- Seasonal variation due to variance in the intensity (brightness) of the sun
- Time of day - Middle of the day will give you highest electricity generation for many systems
- Shading from trees or buildings will reduce electricity output significantly
Secondary effects on generation
- Angle and orientation of the solar power panels - North facing at 30 degrees = 100% efficiency. North at 10 degrees = 94%. A flat roof = 87% efficiency
- Seasonal variations in sunshine hours. In summer you can expect 8 hours of solar power while in winter this drops to about three hours.
- Panel and solar power inverter quality and efficiency - a good inverter will will be up to 98% efficient converting DC power to AC
- Air flow around the system
- Dirt upon bird droppings - built up
Have a look at our Solar System Output Calculator for the approximate output of a well designed solar system in your particular area.