Why is a warehouse roof well suited to commercial solar?

It typically combines a large, largely unshaded roof area with a load profile concentrated in daylight hours — forklift charging, refrigeration, lighting and dock operations — which is close to the best-case load match for solar generation.

What changed with the SRES in 2026?

From 5 August 2026 the government announced eligibility for the Small-scale Renewable Energy Scheme will expand from 100kW to 1MW systems, effective for installations from 1 October 2026, moving that size band onto the more predictable STC mechanism instead of the more volatile LGC market.

Does the SRES expansion apply to a system already installed?

No — it applies to newly eligible systems installed from the 1 October 2026 effective date. A system already accredited under LGCs continues under that arrangement.

Does solar alone stop a demand charge?

Not reliably. Solar reduces total daytime energy draw from the grid, but a demand charge is set by a single peak that can still occur — pairing solar with battery storage is the combination that targets a demand peak directly.

Commercial rooftop solar for warehouses: why the roof and the load line up

A warehouse combines two things commercial solar economics reward most: a large, mostly unshaded roof, and a load profile concentrated in daylight hours. A federal policy change taking effect from October 2026 makes the middle size of system — the size most warehouses actually need — more predictable to finance.

Last updated 2026-08-24

Why a warehouse roof is close to the best case

Commercial solar economics reward two things above almost everything else: roof area with minimal shading, and a load profile that consumes power during the hours the sun is actually generating it. A warehouse or distribution centre typically has both — a large flat roof with few obstructions, and a load dominated by daytime forklift charging, refrigeration, lighting and dock operations rather than evening or overnight demand.

Industry estimates for a facility with a roughly 10,000m² roof put a 500kW rooftop system at roughly $400,000 installed, generating $80,000–$100,000 a year in savings for a four-to-five-year payback before incentives — figures worth treating as an illustrative order of magnitude from installer industry sources rather than a quote for any specific roof, since actual cost and output depend on roof condition, orientation, shading and your site's actual load profile.

The 2026 policy change that improves the math

From 5 August 2026, the Australian Government announced it will expand Small-scale Renewable Energy Scheme (SRES) eligibility for solar PV from 100kW systems up to 1MW systems, effective for systems installed from 1 October 2026, subject to regulations. Before this change, any system over 100kW could only access Large-scale Generation Certificates (LGCs) rather than the Small-scale Technology Certificates (STCs) most home and small-business solar buyers already use.

That distinction matters because LGCs and STCs behave very differently as a financial input. LGC spot prices fell from a Q2 2025 peak of $22.25 in early April 2025 to $16.50 at the end of that quarter, and down to $12.60 by 22 August 2025, with the forward Cal28 price sitting at $10.25 — genuine volatility that makes an LGC-based revenue assumption in a solar business case a moving target. STCs, by contrast, are issued upfront at a broadly predictable value, which is why moving the 100kW–1MW band — the exact range most warehouse-scale rooftop systems fall into — onto the STC mechanism is a real, dated improvement to project financing certainty, not a cosmetic change.

What this means for sizing a system

A system in the newly-eligible 100kW–1MW band installed from 1 October 2026 should be assessed against the STC mechanism's more predictable upfront value rather than the LGC volatility shown above, which changes the payback calculation an installer's quote should be running for you. A system already installed and generating LGCs before that date continues under the LGC arrangement it was accredited under — the change applies to newly eligible systems from the effective date, not retrospectively.

Roof suitability is still the first question before any of the above — covered in building specification for storage — since roof age, structural load capacity for panel mounting, and orientation all constrain what system size a given roof can actually support before the incentive math becomes relevant. Installation cost should be scoped against the wider numbers in warehouse fitout costs rather than assessed as an isolated line item, and a leased site needs the lease terms checked for who actually owns a rooftop system and its output before committing capital to someone else's roof.

A ~500kW system on a 10,000m² roof: roughly $400,000 installed (industry estimate)
SRES eligibility expands from 100kW to 1MW systems from 1 October 2026
LGC spot price: $22.25 (Apr 2025) → $16.50 (Jun 2025) → $12.60 (Aug 2025)
100kW–1MW systems installed from October 2026 move onto the more predictable STC mechanism

Where this connects to the rest of a site's energy plan

Daytime solar generation offsets total energy use, which is a different problem from the peak-demand mechanic covered in warehouse demand charges — solar alone does not reliably prevent a demand spike unless it is paired with storage that can discharge into a specific peak window, covered in battery storage and demand management. State-based schemes layered on top of the federal SRES/LGC framework, covered in state energy incentive schemes, can add further commercial-specific incentives depending on which state the site sits in.

Common questions

Why is a warehouse roof well suited to commercial solar?: It typically combines a large, largely unshaded roof area with a load profile concentrated in daylight hours — forklift charging, refrigeration, lighting and dock operations — which is close to the best-case load match for solar generation.
What changed with the SRES in 2026?: From 5 August 2026 the government announced eligibility for the Small-scale Renewable Energy Scheme will expand from 100kW to 1MW systems, effective for installations from 1 October 2026, moving that size band onto the more predictable STC mechanism instead of the more volatile LGC market.
Does the SRES expansion apply to a system already installed?: No — it applies to newly eligible systems installed from the 1 October 2026 effective date. A system already accredited under LGCs continues under that arrangement.
Does solar alone stop a demand charge?: Not reliably. Solar reduces total daytime energy draw from the grid, but a demand charge is set by a single peak that can still occur — pairing solar with battery storage is the combination that targets a demand peak directly.

Sources

Clean Energy Regulator — Quarterly Carbon Market Report, June Quarter 2025, Large-scale renewable electricity — LGC spot and forward price data for 2025, directly published by the Clean Energy Regulator.
SkyHigh Solar — Commercial Solar Installation: The 2026 Business Buying Guide — Illustrative industry cost and payback estimate for a large-roof commercial system. An installer industry estimate, not a government or utility figure.

Part of our guide to the warehouse power bill.