There are several large sections of a solar power system. The panels on the roof are perhaps the most visible section. But there will also be a solar battery system and a power inverter.
The power inverter performs a vital function, converting the DC power from the batteries into the AC power used by the main wall sockets in the home.
The terms ‘AC’ and ‘DC’ are often not understood by non-technical people. DC power is a constant steady power, as a battery would produce. AC is a power source that alternates at regular intervals. In Australia the home AC power alternates 50 times per second (50Hz). This AC power has advantages when used over long distance cabling. It can be used directly by some home electronic appliances. But other appliances convert the power to DC.
A solar power inverter in Australia will be designed to convert the solar DC battery power to the 240 Volt AC voltage used in Australian Homes. The voltage (240 volt) and frequency (50Hz) are important specifications. But the inverter must also be able to handle sufficient total power for the home.
Voltage and power can be easily confused. Voltage is one aspect of power. All mains plugs in the home will be 240 Volts. But if we use several point all at the same time we are using more power. Both the solar battery storage and the inverter must be capable of handling this amount of power.
The invertor is often rated slightly lower than the solar panels that feed the system. This is because the panels will not always be running to full capacity (it is not always hot and sunny), and also because the not all the energy from the solar panels will be used at one. The panels will charge the batteries by day (12 hours); the batteries will be used day and night (24 hours).
A solar inverter should complies with the relevant Australian Standard. (AS4777).
There is no average household electricity consumption – every home is different. Talk about your individual needs with the solar installers.