Solar Power can be a good investment over the course of its lifespan, providing savings on your electricity costs and contributing to the value of your property.
There are many factors, some of which are listed below, which will impact and determine your solar systems Return on investment
If you qualify for the Queensland 44c feed in tariff you will be able to sell (export) any excess power generated by your solar system back to the grid for more than the current KWH electricity charge. Under a net feed in tariff scheme you will greatly improve the overall benefit you receive from your solar system if you minimise day time electricity use and export excess power to the grid.
However with the Queensland feed in tariff reducing to 8c /KWH it becomes important to try and use the maximum amount of solar power your system produces in your home as you are being paid less for it (if you send it back to the grid) than you pay for electricity.
The quality of the system and its likely lifespan is important, as the electrical output from a very low cost solar panel can degrade significantly over time. This means that initial saving’ from buying a lower quality panel (cheaper)is lost in the long term.
Inverters, switches and hardward could well need replacing over the lifetime of your solar system. Buying good quality equipment with local Australian warranties and service is important in ensuring your solar system continue to operate and generate power. Any downtime means you are losing money.
Most importantly electricity cost will continue to rise, which in itself effectively increases the return on your solar.
The following tables are an estimate of daily and annual expected generation for the Brisbane area:
Data Source: PV-GC spread sheet based on the CEC GC Design Guidelines. The rated output is that achieved in perfect laboratory conditions and does not take into account rain/ cloudy conditions. The CEC design summary software takes these deratings into account when predicting average for any system.
The Solar System generates electricity in proportion to the amount of sunlight on the solar modules and the module temperature. There is no electricity generated at night. The peak generation of power is on a clear cool day when the sun is at a perpendicular angle to the solar modules. Clouds, seasonal variation of solar angle, array soiling, non-optimum orientation and any incidental shading decrease that performance.
A typical Australian house consumes around 18kilowatt hours (kWh) per day so a 1-2kW system displaces an average of 25-40% of your average electricity bill. Solar panels produce more energy in summer than they do in winter. Any shading on the solar array will reduce the output of the system.