The short answer
- Does my rooftop rebate change? No. The explanatory statement says a
system of no more than 100 kW
will continue to be eligible for the same support that has previously applied under the SRES
. Installed in 2026, that is five years of generation credited up front; in 2027, four. - What is new? Systems over 100 kW and up to 1 MW installed from 1 October 2026 can now use the small-scale scheme, and each is credited with five years of generation whichever year to 2030 it goes in. The Clean Energy Regulator expects applications to open in mid to late November.
- Will it cost me? Retailers buy the certificates. The explanatory statement expects the effect on consumer bills to be minor relative to the potential benefits, without a figure. On our rough arithmetic, if mid-scale capacity doubles as the statement says it could, the extra certificates add about 0.6 to 0.9 of a percentage point to the small-scale technology percentage, the measure of how many certificates retailers must buy, which is 11.67 per cent for 2026.
Five years, every year
Certificates for a solar system are not paid as it generates. The system is credited up
front with an estimate of what it will produce over a set number of years, the deeming
period, and that is the number its owner can turn into certificates and, through the
installer, into a discount. For systems up to 100 kW the regulator’s rule is simple:
The deeming period decreases by one year each year until 2030 when the scheme ends.
The new regulations, made on 16 September and registered on 17 September, take mid-scale
solar out of that countdown. The operative words, added to regulation 19D, give a right to
create certificates within 12 months of installation and for the period of 5 years
. The
explanatory statement spells out what that means: mid-scale systems will be
eligible to create certificates representing 5 years of generation regardless of the
installation year
, for systems installed between 1 October 2026 and 31 December 2030.
The regulator’s mid-scale page calls it a key feature:
eligible mid-scale solar systems (100 kW to 1 MW) will have the benefit of a fixed 5-year
deeming period
.
One square is one year of deemed generation. Up to 100 kW: the Clean Energy Regulator’s “Deeming period by installation year” table. Over 100 kW to 1 MW: new regulation 19D(2)(e) and the explanatory statement, which apply the five years to systems installed from 1 October 2026 to 31 December 2030. How many certificates a year of generation is worth also depends on capacity and the postcode’s zone rating, which are the same for both kinds of system.
So the gap opens from next year. Installed on the same day in 2029, a 500 kW array on a
packing shed is credited with five years of generation for every kilowatt; a 6.6 kW system on
a house in the same postcode, with two. In 2030 it is five against one. The government’s
reason for the support is in the statement: roof space on commercial, industrial and
agricultural buildings is under utilised
.
Who pays for the certificates
Small-scale certificates are bought by the businesses that sell electricity. In the
explanatory statement’s words, Liable entities (mainly electricity retailers)
acquire these certificates which they must surrender annually to the Regulator
. How many
they must buy is set each year by the small-scale technology percentage, 11.67 per cent for
2026. The battery rebate runs on the same certificates but is kept out of that percentage,
because the department buys the battery certificates itself. Nothing in the regulations or on
the regulator’s percentage page sets mid-scale certificates aside in that way, and the
two documents describe the cost to households very differently:
Battery certificates
Clean Energy Regulator, small-scale technology percentage page, last updated 18 September 2026No costs will be passed onto energy retailers or households.
Mid-scale solar certificates
Explanatory statement to the Mid-scale Solar Regulations 2026, page 3While SRES compliance costs are met by electricity retailers, the impact on consumer bills is expected to be minor relative to the potential benefits.
Both sentences verbatim. The regulator’s page was updated on 18 September with a notice about mid-scale solar and still carries the battery sentence only.
The department’s own scheme page goes further the other way. Under the heading on
how the expansion helps, it lists what installing solar can do, ending with reduce electricity
costs for all consumers
. Neither document puts a number on the cost or on the
saving. “Minor relative to the potential benefits” is a comparison, not a size.
How big it could get
The explanatory statement gives the two numbers that frame it. Under the large-scale scheme
since 2001, around 780 MW of mid-scale solar capacity has been installed in Australia,
with around two-thirds of that in the last six years
. And: The new support could double that
capacity in the period to 2030.
For comparison it adds that in April, May and June 2026
alone, over 1 gigawatt (GW) of small-scale solar capacity (systems below 100kW) was installed
with support from the SRES
.
Bars drawn to scale with 1 GW (1,000 MW) as the full width; the statement says “over 1 gigawatt” for the quarter, so that bar is a floor. Mid-scale capacity was installed under the large-scale scheme; the quarter’s figure is small-scale solar supported by the SRES. Explanatory statement, page 3.
Capacity is not certificates, because each mid-scale kilowatt carries five years. We worked out what a doubling would mean in certificates, using the regulator’s own zone ratings and its 2026 working. This is our arithmetic, and a rough one.
4.6m to 6.3m
Certificates in total if about 780 MW more is installed by 2030, at five years each and zone ratings of 1.185 to 1.622.
Our arithmetic
1.2m to 1.6m
A year, if spread evenly over the four calendar years 2027 to 2030.
Our arithmetic
4.8% to 6.6%
Of the 24.1 million certificate creations the regulator estimated for 2026, which exclude battery certificates.
Our arithmetic, CER 2026 estimate
0.6 to 0.9
Percentage points on the small-scale technology percentage, on the electricity figures in the regulator’s 2026 working. The 2026 percentage is 11.67.
Our arithmetic, CER 2026 working
Method: 780,000 kW multiplied by five years and by the zone rating (1.185, the lowest, to 1.622, the highest, in megawatt hours per kW a year from the regulator’s postcode table), following the regulations’ method of zone rating times rated capacity, before rounding. The yearly figure divides by four; installations actually run from October 2026 and certificates can be created up to 12 months after installation, so real creations will be lumpier. The percentage points divide the yearly figure by 184,147,676 MWh, the regulator’s 2026 estimate of relevant acquisitions (219,610,453 MWh) less exemptions (35,462,777 MWh). “Could double” is the statement’s possibility, not a forecast. This sizes certificates only; it does not convert them into dollars on a bill, which depends on the certificate price and on how retailers pass costs through.
What a business has to do, and when
The mid-scale tier keeps the small-scale scheme’s installer and product rules and
adds evidence that planning and approval requirements were met. It drops two documents a
household gets: there is no designer statement and no retailer statement, the one that tells
a home buyer about sizing and payback. The statement’s reasoning: That
information is expected to be provided in contract negotiations by businesses that invest in
mid-scale solar (photovoltaic) devices
. A business also has to choose: the regulator warns
that if you choose to apply for STCs for your mid-scale solar system, you will not be able to
create REGO certificates for the deeming period
, REGO being the Renewable Electricity
Guarantee of Origin scheme.
- 5 August 2026Announced by the Minister for Climate Change and Energy at the National Press Club.
- 26 to 28 August 2026Targeted consultation on the draft with the Smart Energy Council and the Clean Energy Council; the Clean Energy Regulator was consulted on administration.
- 16 and 17 September 2026Regulations made, then registered.
- 1 October 2026In force. Applies to systems installed from this date.
- Mid to late November 2026Applications expected to open, per the regulator; it gives no fixed date.
- 31 March 2027The 2027 small-scale technology percentage must be set by this date, the first one set with mid-scale systems in the scheme.
- 31 December 2030Last installation date for the five-year deeming period.
Dates from the explanatory statement (announcement, consultation, commencement,
the 2030 end date), the regulations themselves (made and registered), the regulator’s
mid-scale page (applications) and its percentage page, which says The STP must be set
by 31 March each year, otherwise a default percentage is used.
What we said in August, against the regulations
We covered the announcement on 16 August, before the regulations existed, and flagged two things to check. Both now have answers, and one of our own examples was wrong.
| What we wrote | What the documents now say | Verdict |
|---|---|---|
| Read literally, the department’s sentence meant a flat five years for mid-scale in each year to 2030. We called it our reading, not a finding. | Regulation 19D(2)(e): five years. The statement: regardless of the installation year. | Confirmed |
| Neither announcement said anything about cost recovery. | The statement says retailers meet the costs and the bill impact is expected to be minor relative to the potential benefits. | Answered in words, not numbers |
| A system up to 100 kW installed in 2029 “earns roughly one year of certificates”. | The regulator’s table gives two years for 2029 and one for 2030. | We were wrong; corrected on that page |
| No designer or retailer statement for mid-scale. | Regulations items 12, 14, 17 and 18: an installer statement only. | Confirmed |
Our 16 August story is The small-scale solar scheme expands tenfold on 1 October; its wording is quoted in plain quotation marks.
Our view
This is opinion, built on the documents above. Crediting a 2029 business array with five years when a 2029 house gets two is a deliberate choice, and a defensible one. Under the falling count that applies to houses, a business array installed in 2030 would be credited with one year, and the case the statement makes, under-used commercial roofs generating electricity where it is consumed, holds up.
The weaker part is the disclosure. “Minor relative to the potential benefits” sizes neither the cost nor the benefit. On our rough arithmetic a doubling would add certificates equal to about 5 to 7 per cent of the regulator’s 2026 estimate each year, and the regulator’s non-binding estimates for 2027 and 2028, 19.8 million and 14.3 million, are lower than 2026’s, so the same mid-scale volume would be a larger share. That is not alarming, and it is not nothing. The regulator already shows its working for the percentage line by line. Its 2027 working should show the mid-scale estimate as a line of its own, so a household can see what this part of the scheme adds. We will report the 2027 percentage when it is set, and whether its working shows that line.