What is AC Solar?
Conventional direct current (DC) solar systems consist of a number of solar modules wired together in series configuration to create ‘strings’ of modules, with a combined output voltage typically between 200 and 600 volts DC. This is then fed into a single large inverter, which converts the voltage to 240 volts AC for connection to the electricity distribution system.
DC solar system have high DC voltages that are challenging to provide electrical protection. Poor DC connections have caused roof fires.
Alternating current (AC) solar systems use micro inverters (typically one microinverter per solar panel) to convert the output of each solar panel directly to 240 volts AC. This eliminates the need to install DC cabling between modules or to install a large centralised inverter, and greatly simplifies the installation, monitoring and maintenance of the system. Microinverters provide all of the functionality of conventional string inverters – such as automatic disconnect and reconnect when the grid fails – and are required to conform to the same standards (including AS4777).