Methodology

All figures come from the Clean Energy Regulator (CER) small-scale installation postcode data: four CSV files (solar installations, solar capacity, battery installations and battery capacity) with data to Sep 2026. The CER publishes them monthly under a Creative Commons Attribution 4.0 licence.

What is counted

An installation is a small-scale system (solar panels up to 100 kW, or a battery) for which small-scale technology certificates were created and registered with the CER. Systems that were never registered, or whose certificates failed validation, are not included. A record may be a new system, an extension of an existing system or a replacement, so the count is not the number of homes with solar and is never presented as a household take-up rate.

Recent months are provisional

Certificates can be created up to 12 months after installation, so the latest 12 months (Oct 2025 to Sep 2026) are incomplete and will rise. The CER also corrects earlier months. This site shows the figures exactly as published in the current files and labels recent months as provisional: in tables with a ring symbol and the word “provisional”, and in figures as outlined (unfilled) spokes and dotted lines on a shaded band. It does not treat the difference between two releases as new installations.

Units

Solar capacity is rated power output in kilowatts (kW). Battery capacity is usable storage in kilowatt-hours (kWh). The two are different units and are never added together or drawn in the same figure. Average system size (kW per installation, kWh per battery) is calculated by this site by dividing capacity by installations for the same area and period.

Years, totals and the cumulative line

The CER publishes 2001–2010 as one combined figure and monthly figures from January 2011 (solar) and July 2025 (batteries). Yearly figures on this site are sums of the monthly figures. Cumulative figures are the CER “Total” column; the cumulative line adds each month to the 2001–2010 figure. Battery figures before July 2025 are not collected in this dataset; they are shown as “not collected”, never as zero.

Postcodes and states

Postcodes are the installation postcodes recorded by the CER (Australia Post postcodes). They are not the ABS Postal Areas (POA) used in census statistics, and the two are not joined on this site. State and national figures are sums of postcode rows: each postcode is assigned once to a state by its Australia Post number range. A few postcodes near state borders also cover localities in a neighbouring state (they are marked on their pages), and postcodes for external territories (Norfolk Island, Christmas Island, Cocos (Keeling) Islands) count only in the national total. These sums are therefore not official CER state totals. Postcode 0000 (an invalid postcode in the CER files) is excluded.

What is not included

This site does not estimate installation prices, savings, rebates, payback periods, installer ratings or electricity generated: none of these are in the CER data.