Best Solar Proposal Software Australia: 2026 Guide

Australian solar quoting has two variables that no other market shares, and generic proposal software handles neither. The first is STC deeming: the federal rebate is created from system size, the postcode’s solar zone rating, and the years left in a scheme that ends in December 2030, so the same 6.6 kW system is worth less this year than last and different amounts in Cairns and Hobart. The second is export limits: distribution networks increasingly cap or dynamically curtail export, so a proposal built on unconstrained feed-in overstates income on exactly the systems most likely to be constrained. This guide compares the platforms Australian installers should shortlist on those two things first.

Short version. The best solar proposal software for Australian installers in 2026 is SurgePV, because it calculates STC deeming from system size and solar zone, applies AS/NZS 5033 and AS 4777.2 checks at design time, models DNSP export limits, and generates the customer document from the same engineering record. OpenSolar is the default for simple residential on cost. Solargraf suits crews that already own a design tool.

Australia has the highest per-capita rooftop solar penetration in the world, which means the market is mature, competitive, and unusually well-informed. Customers here compare quotes closely and often know their network’s export rules. For the design-side comparison see our solar design software Australia guide, and the global solar proposal software ranking for the category without the Australian lens.

What An Australian Solar Proposal Has To Get Right

STC deeming, computed not assumed. The Small-scale Renewable Energy Scheme creates certificates for systems under 100 kW based on capacity, solar zone, and remaining scheme years to December 2030. Most retailers pass the value through as an upfront discount in exchange for assignment. The deeming period shortens each year, so a rebate figure hardcoded in a template decays annually without anyone noticing. SurgePV’s STC scheme guide covers the mechanics.

CEC accreditation and approved products. STC eligibility requires a CEC-accredited installer holding a relevant electrical licence and maintaining accreditation annually, plus CEC-approved components. Both halves matter. See SurgePV’s CEC accreditation guide.

AS/NZS compliance at design time. AS/NZS 5033:2021 sets DC cable sizing, string protection fusing, array and frame earthing, arc fault detection, and commissioning testing. AS 4777.2:2020 sets grid connection behaviour including volt-watt and volt-VAR response, ride-through, and anti-islanding. AS/NZS 5139:2019 governs battery installation. The AS/NZS 5033 guide and AS 4777.2 guide cover the detail.

DNSP export limits. Ausgrid in NSW, Energy Queensland, SA Power Networks, and Western Power all set their own limits and connection conditions, and constrained areas increasingly get dynamic or zero export. See the export limits guide.

The Two Errors That Cost Australian Installers Money

The deeming error. Because the scheme ends in December 2030, the deeming period shortens every year on 1 January. A template carrying last year’s per-kW rebate overstates the discount, and the gap widens each year until the scheme closes. Solar zone compounds it: the same system deems differently in Zone 1 and Zone 4, so a national flat rate is wrong nearly everywhere.

The consequence is the same in both cases. The installer who models honestly looks more expensive than the one who does not, and loses deals on a comparison that was never valid. The defence is to show the constraint explicitly in the proposal, because a customer who understands the export limit will accept a smaller system or a battery rather than assume you are padding.

The Platforms Australian Installers Should Evaluate

1. SurgePV, the integrated pick

Proposal generated from the same project record as the design. STC deeming from size and solar zone, AS/NZS 5033 and AS 4777.2 checks, DNSP export limit modelling, 8,760-hour module-level shading, bankable P50, P75, P90, and white-label proposals with e-signature. $1,299 to $1,899 per user per year flat.

2. OpenSolar

The default in Australian residential, and free at entry, which is a genuinely strong position. STC handling is solid. Shading is simplified, and add-ons stack at commercial scale. See our OpenSolar alternative breakdown for where the free tier stops paying off.

3. Solargraf

Fast, clean residential documents with e-signature, Enphase-owned. Sits downstream of a design tool. Roughly $1,200 to $2,400 per user per year. More in our Solargraf alternative review.

4. Aurora Solar

Deep residential design built for US utility structures. No STC deeming, no CEC product list, no DNSP export rules. Defensible only for commercial-heavy teams willing to handle Australian specifics manually. See our Aurora Solar alternative comparison.

5. Pylon

Fast residential proposals for sales-led teams, limited engineering depth, per-feature pricing. Covered in our Pylon alternative comparison.

6. SunSniffer and local proposal tools

Several Australia-specific quoting tools handle STC and CEC paperwork well but carry thin simulation. Workable for straightforward residential where the design question is already settled.

7. Spreadsheet plus a design tool

Still common in smaller operations. The main source of stale deeming rates in circulating quotes, because nobody updates the sheet on 1 January.

Australia Solar Proposal Software Comparison

Worked Example: 10 kW In Adelaide, With And Without An Export Limit

An illustrative calculation showing the size of the export limit effect. Inputs: 10 kW array, 1,550 kWh per kW specific yield, 15,500 kWh generation, 6,200 kWh self-consumed, import at 42c per kWh, feed-in at 5c per kWh.

The headline gap is $120, which looks small. That is the point worth making to the customer: at a 5c feed-in tariff, curtailment barely matters, and the 2,400 kWh being thrown away is worth $120 as export but $1,008 if shifted into household use. On these numbers the export limit is not the problem. The 5c tariff is, and it is the strongest battery argument in the Australian market. A proposal that only reports total savings hides that entirely.

Who Should Choose What

• Choose SurgePV if you want STC deeming, export limits, AS/NZS checks and proposals in one license, or you run commercial alongside residential.
• Choose OpenSolar if you are residential-only and entry cost is decisive, accepting simplified shading.
• Choose Solargraf if you already own a design platform and want a faster customer document.
• Choose Aurora only if commercial design depth outweighs handling Australian specifics manually.
• Choose Pylon or a local quoting tool if proposal speed on straightforward residential is the whole job.
• Drop the spreadsheet if it still carries a hardcoded per-kW STC figure, which decays every January.

After signing, pipeline and follow-up move to a CRM. QuickEstimate takes the handoff from SurgePV by API.

The Bottom Line

Australia is the most mature rooftop market in the world, and the two things that decide an Australian proposal’s accuracy are both moving targets: a rebate that shrinks annually and export rules that tighten locally.

• Recompute STCs, never hardcode them. Deeming shortens every 1 January and varies by solar zone, so any flat per-kW figure in your template is already wrong somewhere.
• Model the export limit and show the curtailed energy. At a 5c feed-in tariff, curtailed kWh are the clearest battery argument you have, but only if the proposal shows them.