Over the past few years, the price of solar systems has significantly dropped. Today, the installation costs around $4,000 to $6,000 for a 4kW solar system. Suppose you plan on using a high-quality optimizer or microinverter. In that case, the cost for that solar system installation is usually 20% more than the average.

However, take note that there are several factors that can affect the overall cost of solar systems—for example, its size and the company that will be installing them. But, most of the PV system cost is subsided by the solar rebate scheme of the Australian government. Nonetheless, the cost is much more affordable than before.