Background
Solar panels, which are made of silicon, convert sunlight into electricity [direct current]; they were first made in 1954. With the development of satellites, solar panels were used as the power source. Since 1954 efforts have been made to reduce cost and improve performance. Sliver cell technology currently being developed in Australia will produce panels that are made from less silicon, are more efficient in coping with shading and operate at cooler temperatures thus improving efficiency. The electricity created by solar panels can be stored in batteries for future use OR converted to alternating current via an inverter and fed into the electricity grid [grid connected]. If there is a power black-out, the former will continue to provide power via the batteries while the latter will not.
The picture above shows our grid connected 1.67 kW system (there are ten 167 watt Sharp panels) connected via a Fronius inverter to a CO-GEN meter which records power drawn from the grid and power we put into the grid.
Process for installing a grid connected system
- look at your electricity bill to determine your average daily usage
- decide how much of this you ideally wish to produce via solar
- find out from your weather bureau the average daily sunlight for where you live
- determine whether your house has a north facing roof clear of any shading from trees or other buildings
- now do the sums e.g. 10 x 167 Watt panels will produce 1670 Watts. In Melbourne, Australia, average sunlight hours are approximately 4.2 hours, thus electricity produced will average 7014 Watts per day
- each of these 167 Watt panels measures 1575x826 mm
- after deciding how many panels you are able to install:
- hunt for the best installation price; this may be your current supplier as per your electricity bill - remember that the Australian Government gives a rebate for small scale systems. You can also assign to a supplier what are called the Renewable Energy Certificates for your system [at the moment this is a piddling amount].
- you will be signing contracts, including one with your electricity retailer [this is the group that provides the power to your supplier] and one with the supplier who will be buying your generated power [go for the supplier that buys your power for the same rate they charge for the power that you draw from the grid]
- once the panels are installed, the installers will arrange for an inspection of the system - once passed:
- the electricity retailer will be notified and will install a CO-GEN metre [this quantifies how much power you use and generate]; prior to this your supplier may need to take a metre reading