In July this masthead charted the first eleven months of the scheme from the same source, and warned in passing that the latest month always looks smaller than it turns out to be. That was the right caution, but it was only a caution. The Regulator has since published its June edition, and because the earlier figures were recorded at the time, the two files can be set against each other. That turns the warning into a measurement, and the measurement is larger than the warning implied.
The year, month by month
Validated battery installations per month, summed across the Hunter postcode set listed in the methodology note. Source: Clean Energy Regulator SRES postcode data, installations workbook, SGU-Battery sheet, data as at 30 June 2026.
The shape is a scheme that took most of a year to find its stride. From 842 systems in the opening month the pace wandered through spring, dipped over January to 760, then climbed steeply: 1,033 in February, 1,324 in March and 1,751 in April, more than double the opening month. Then the line appears to fall off a cliff. It is the cliff that is not real.
What two editions of one file reveal
The Regulator says as much itself, in a note printed at the top of every sheet in the
workbook: renewable energy target legislation allows a 12 month creation period for
registered persons to create their certificates
, and so the 2025 and 2026 figures
will continue to rise
. An installer who fits a battery in June has until the
following June to lodge the paperwork that puts it in this dataset. Recent months are
therefore always partial.
What the Regulator does not publish is how partial. Comparing its 30 June edition against the 31 May one answers that for every month at once, because each month appears in both files and any difference is late paperwork arriving.
Percentage increase in the Hunter battery count for each month, measured between the workbook current to 31 May 2026 and the workbook current to 30 June 2026. Our calculation from the two editions; the earlier figures are those this masthead published on 18 July 2026.
The decay is orderly. The month that was newest when we last looked, May, has grown from 350 to 624, a rise of 78.3 per cent in about eight weeks. One month further back, April rose 6.8 per cent, which is why its 1,640 is now 1,751. Two months back, March moved 2.7 per cent. By three months back the correction is 1.4 per cent, and beyond four months nothing shifts by more than half a per cent. In practical terms this dataset takes roughly three months to settle, and only the last two months are seriously incomplete.
Applying that to June’s printed 420 is straightforward arithmetic: if it fills in as May did, it lands somewhere near 750. We would not call that a forecast. It is one observed revision cycle rather than a model, and a single cycle can be atypical. But it is grounded enough to say what June is not, which is a collapse in demand. The honest summary of the year is that installs were still climbing through autumn, and the last two bars cannot yet be read.
Where the batteries went
| Postcode | Systems | kWh | Avg kWh |
|---|---|---|---|
| 2320 Maitland area | 938 | 24,722 | 26.4 |
| 2287 | 713 | 18,437 | 25.9 |
| 2285 | 696 | 18,186 | 26.1 |
| 2324 | 637 | 14,970 | 23.5 |
| 2322 | 630 | 16,376 | 26.0 |
| 2290 | 628 | 15,385 | 24.5 |
| 2325 Cessnock | 624 | 16,595 | 26.6 |
| 2280 Lake Macquarie | 602 | 15,324 | 25.5 |
| 2321 | 589 | 15,689 | 26.6 |
| 2283 | 581 | 14,668 | 25.2 |
Maitland’s 2320 leads the region again, as it did on every measure in the earlier piece, and its lead has widened from 877 systems to 938. The spread across the top ten is narrow, which is the more interesting fact: nine postcodes sit between 581 and 713, so this is a region-wide pattern rather than a couple of enthusiastic suburbs. Average system size barely varies, from 23.5 kWh to 26.6 kWh, clustering near the 25.8 kWh Hunter-wide average. That consistency suggests households are mostly buying a standard product rather than sizing to their own consumption.
For context, the same workbooks count 97,894 rooftop solar systems and 696,822 kW across those postcodes since 2001. A year of batteries has reached the equivalent of roughly one in nine of those solar households.
How we did this
Both Clean Energy Regulator workbooks, capacity and installations, were downloaded on 3 August 2026 and summed with a script over a fixed set of 29 Hunter postcodes: 2300; 2280 to 2287, 2289 and 2290; 2318 to 2327; 2328, 2329; 2330; 2333; and 2334 to 2337. The set is deliberately identical to the one used in July, so the two editions are comparable. Battery figures come from the SGU-Battery sheets, which begin in July 2025 because that is when the scheme began.
One trap worth recording for anyone repeating this: the grand total is the last column headed “Total Installation Quantity”. A column headed “Historic Total Installation Quantity (2001 - 2010)” sits near the start of each sheet and matches a naive search, but covers only the first decade.
The revision figures are our own calculation, comparing each month’s value in the 30 June workbook against the value this masthead published on 18 July 2026 from the 31 May workbook. Those earlier figures were independently re-derived from the source file on 21 July 2026 before being relied on here.
What we have not done. We have not asked the Regulator whether the lag differs by state, technology or installer size, so the pattern described is the Hunter’s and one cycle of it. We have not adjusted any published figure upward; every number above is as printed in the source. Postcodes 2331 and 2332 have no rows in either workbook, which we have not been able to explain and have not counted.
Sources
- Clean Energy Regulator, Small-scale installation postcode data: the landing page, stating the data is current as at 30 June 2026 and last updated 23 July 2026. Read 3 August 2026.
- Clean Energy Regulator, SRES postcode data, installations: the SGU-Battery and SGU-Solar sheets, the monthly series, the postcode counts, and the 12-month certificate-creation note quoted above. Downloaded 3 August 2026.
- Clean Energy Regulator, SRES postcode data, capacity: usable battery capacity in kWh and solar rated output in kW. Downloaded 3 August 2026.
- The Connection Point, Eleven months, 10,072 home batteries: the 31 May edition figures against which the revisions here are measured.
Install batteries in the Hunter, or read this data differently? Tell us and we will check it against the workbooks and log the outcome here.