A major change announced this month could make larger commercial solar systems significantly more attractive for Australian businesses.
The Australian Government has announced plans to expand the Small-scale Renewable Energy Scheme so that eligible solar systems between 100kW and 1MW can receive Small-scale Technology Certificates, or STCs. The change is intended to apply to systems installed from 1 October 2026, subject to the required regulations being made.
Until now, the upfront STC discount has generally applied only to solar systems below 100kW. This is one reason many commercial projects have historically been designed around the 99kW mark, even where a business had the roof space and electricity consumption to justify a much larger system.
For warehouses, manufacturers, clubs, car dealerships, shopping centres and other businesses with significant daytime energy use, the proposed change could alter the economics considerably. The Federal Government has said the expansion is expected to reduce the cost of installing medium-scale solar by around 20 per cent.
The important point is not simply to install the biggest solar system that will fit on the roof. Businesses should review at least 12 months of electricity data and match the system to their daytime load, future growth, available roof area and network export limits.
A well-sized commercial solar system can reduce the amount of electricity purchased from the grid for decades. Batteries can then be considered where there is strong evening consumption, demand charges or an opportunity to shift energy into more expensive periods.
For businesses that previously investigated 100kW-plus solar and found the numbers difficult, it may be worth revisiting the project.
With the proposed rules changing from 1 October, the financial case for making better use of large commercial rooftops could look very different.