Perth and most of WA are in STC Zone 3, with Zone 1 and 2 multipliers in the Kimberley and Pilbara regions.
Western Australia's incentive stack mirrors Queensland and South Australia: federal STCs, no state VEEC scheme, no PDRS-style battery rebate. Perth (6000) sits in STC Zone 3 at 1.382; a 100 kW system installed in 2027 earns roughly 552 STCs over the scheme's remaining 4 years. The multiplier climbs heading north along the coast: Broome (6725) sits in Zone 2 at 1.536, and climbs again in the Pilbara, where Port Hedland (6721) sits in Zone 1 at 1.622, about 17% more STCs than Perth for an identical system, reflecting the much stronger solar resource across WA's north.
Above the STC ceiling (1 MW of site capacity from 1 October 2026, 100 kW before), WA commercial systems earn LGCs on the balance the same way as the rest of the country, one certificate per MWh of actual generation, claimed as ongoing annual revenue. WA businesses adding a battery use the federal Cheaper Home Batteries Program rather than a state rebate, the same tiered weighting (100% for the first 14 kWh, 60% for the next 14, 15% up to 50 kWh) that phases down nationally every six months to 2030.
WA commercial solar installations can access the following incentive schemes.
STC eligibility moved from 100 kW to 1 MW of site capacity for solar installed from 1 October 2026 (Mid-scale Solar Regulations, registered 17 September 2026). The 100 kW limit still governs anything installed before that date, and capacity above the first 1 MW earns LGCs. Read the announcement.
Adjust system size to see your WA incentive breakdown at current certificate prices.
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The zone multiplier determines how many STCs are generated per kilowatt of installed capacity. A multiplier of 1.382 means a 100 kW system in Perth installed in 2027 generates 552 STCs over the remaining deeming period (4 years to 2030), worth approximately $21,313 at current certificate prices, less a 3% provider fee.
Large-scale Generation Certificates provide annual recurring revenue for solar capacity above 1 MW (above 100 kW for installs before 1 October 2026) in Western Australia. Unlike the one-time STC discount, LGCs generate income every year based on actual electricity production.
One LGC is created per megawatt-hour (MWh) of generation. At a current net price of $7/LGC (the market less a 5% provider fee), a 150 kW system in WA generating approximately 202 MWh per year would earn roughly $1,443/year in LGC revenue.
The 99 kW design ceiling is disappearing. Here is what solar professionals need to re-size, re-quote across the 1 October start date, and add to proposal templates before then.
Above the STC ceiling (1 MW of site capacity from 1 October 2026, 100 kW before), solar earns LGCs annually instead of an upfront STC discount. Here is how the scheme works and what a certificate is really worth in 2026.
Perth (6000) sits in STC Zone 3, a 1.382 multiplier.
It steps up twice. Broome (6725) sits in STC Zone 2 (1.536), and the Pilbara, Port Hedland (6721), sits in STC Zone 1 (1.622), about 17% more STCs than Perth for an identical system, because WA's north gets substantially more solar irradiance than the south-west.
No, WA does not run a state battery certificate scheme; batteries use the federal Cheaper Home Batteries Program instead, the same tiered weighting (100% for the first 14 kWh, 60% for the next 14, 15% up to 50 kWh) available nationally.
Yes, solar capacity above 1 MW (above 100 kW for installs before 1 October 2026) earns Large-scale Generation Certificates, one per MWh generated, claimed annually. The system is split: upfront STCs up to that ceiling, LGCs on the balance.
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