Solar Quoting Software for Australian Installers (2026)

In short: solar quoting software turns a customer’s roof and electricity data into a sized system, a payback figure, and a client-ready proposal. In Australia the tool also has to get the incentive maths right: STCs (federal, zone-rated, deeming to 2030), VEECs (Victoria only, for 30–200 kW systems, stacking on top of the federal certificates), and LGCs (federal, for systems over 100 kW, earned annually on metered generation). Get any of those wrong and the payback number on the proposal is wrong before the customer even reads it. The two workflow philosophies, sizing from the electricity bill versus sizing from roof irradiance, produce different answers on the same site, and picking the wrong one for your job mix costs you accuracy or speed. The right tool for a residential volume business is rarely the right tool for a commercial and industrial (C&I) shop.

Every solar installer eventually hits the same wall: spreadsheets do not scale. One quote a week is fine in a spreadsheet. Ten quotes a week with different tariffs, different roof shapes, and a customer asking why last month’s STC estimate does not match this month’s is not. That is the gap solar quoting software fills, and in Australia it is a different problem to the US or European market, because our incentive stack (STC, VEEC, LGC, and a growing pile of state battery schemes) has no direct equivalent overseas. This guide covers what the category actually does, why Australian incentive handling is where generic tools go wrong, the real difference between bill-first and roof-irradiance-first quoting, and the criteria that matter when you choose between tools.

What Solar Quoting Software Actually Does

Strip away the marketing and the category does four jobs: turn inputs (a roof, a bill, a consumption profile) into a sized system; run that system against local weather data to model production; calculate the incentives and financing that apply; and package the result into something a customer can read and sign. Some tools are narrow (a roof-measurement plugin, or a rebate calculator on its own) and some cover the whole quote-to-proposal chain.

The distinction that matters for evaluating tools is whether the software is a solar CRM (pipeline, follow-ups, e-signature, job handoff to install) with a sizing feature bolted on, or solar proposal software built around the sizing and financial model, with lead tracking bolted on. Most installers running commercial work want the latter, because a wrong payback number sinks a deal that pipeline tracking never touches. Commercial solar software specifically needs demand charges, TOU structure, and multi-scenario comparisons that residential-first tools often skip.

Why Generic Sizing Software Gets Australian Incentives Wrong

A tool built for the US market has no concept of an STC zone rating or a VEEC activity code, and even software written for the Australian market can get the detail wrong if it was not kept current. Three schemes do most of the damage when mishandled:

• STCs (Small-scale Technology Certificates). Federal, for systems up to 100 kW, calculated from a zone rating (1.185 to 1.622 depending on postcode) and a deeming period that shrinks by a year each 1 January, down to a single year for a 2030 install. A tool with a stale deeming year or the wrong zone for a postcode will overstate the rebate, sometimes by thousands of dollars on a 50 kW system. Run the exact numbers for a postcode on the STC calculator.
• VEECs (Victorian Energy Efficiency Certificates). Only apply in Victoria, and only to commercial systems of 30–200 kW (VEU Activity 47A/47B). They stack on top of the federal certificates – STCs up to 100 kW, LGCs above – so a tool that treats them as an either/or with STCs, or forgets them on a Victorian job, is quietly costing the customer money.
• LGCs (Large-scale Generation Certificates). For systems over 100 kW, created annually against metered generation rather than deemed upfront like STCs. A tool that treats every system the same way past the 100 kW line, or ignores LGCs entirely because it was built for the residential market, misses ongoing revenue that matters a lot on a C&I proposal.

Then there is the state layer: NSW’s Peak Demand Reduction Scheme (PDRS) and Energy Savings Scheme (ESS), the federal Cheaper Home Batteries discount, and the new NSW battery activities (BESS1–BESS5) landing through 2026. A bolt-on rebate field is clearly not enough for serious commercial quoting. Scheme parameters change yearly, and software that is not actively kept current against Clean Energy Regulator and state-scheme updates drifts out of date within a season, leaving the installer to explain the gap at handover.

Bill-First vs Roof-Irradiance-First Quoting

There are two ways to size a system, and they start from opposite ends of the same problem. Roof-irradiance-first starts with the roof: satellite or drone imagery gives orientation, tilt, and shading, a production model (PVWatts-style, run against local TMY weather data) estimates generation, and the system is sized to fill the usable roof area or hit a target offset percentage. Bill-first starts with the electricity bill or interval meter data: the actual consumption shape, tariff structure, demand charges, and self-consumption behaviour drive the system size, and the roof is checked afterward to confirm the array physically fits.

Neither approach is wrong on its own terms. A residential installer doing volume with a standard retail tariff and no demand charges can get a serviceable quote from roof geometry and an average consumption assumption: the roof is the constraint, and the bill is simple enough to approximate. A commercial installer quoting a warehouse with a TOU tariff and a demand charge cannot: sizing off the roof alone risks a system that generates plenty of midday power the site cannot use, exported at a feed-in tariff a fraction of the retail rate, which wrecks the payback the customer was sold. For C&I work, start from the bill. The roof check comes second, to confirm what the load-driven size actually needs in panel area.

Criteria for Choosing a Quoting Tool

Once you know which workflow your job mix needs, the shortlist comes down to a handful of concrete checks:

• Does it ingest real consumption data, not just an address? CSV upload or interval meter data support matters far more for commercial accuracy than another satellite roof-measurement feature.
• Does it model TOU tariffs and demand charges natively? A flat c/kWh assumption is fine for a simple residential quote and wrong for almost every commercial site.
• Is the incentive engine current and correct? Ask the vendor how STC zone ratings, VEEC activity factors, and LGC eligibility are kept up to date, whether it stacks VEECs on the federal certificates for an eligible Victorian system, and whether it enforces the 100 kW STC/LGC boundary rather than paying the same capacity twice.
• Does it produce a proposal you can actually send? A sizing engine with no branded, exportable output means building the client-facing document by hand anyway.
• Does it model batteries? Storage needs hourly dispatch simulation against the load profile, not a flat capex-vs-savings guess.
• Does the vendor track scheme changes? 2026 alone brought new NSW battery activities and an updated federal battery discount. A tool that lags a scheme change by a quarter leaves you re-quoting deals that already went out the door.

Where a Bill-First Tool Like Amperage Fits

Amperage is one option here, built around the bill-first workflow for Australian commercial and industrial quoting: upload a bill or consumption CSV, get a sized system with STC, VEEC, LGC, and PDRS handling built in, and export a branded proposal. It is not the right fit for every installer. A residential-volume business running mostly off satellite roof measurement and simple retail tariffs may get more from a roof-irradiance-first tool built for that speed. Match the tool to your job mix: if most quotes start with a bill and a demand charge, look for software built around that; if most start with an address and a roof, look for the other kind. See the bill-first approach on a real bill at bill analysis software, or book a demo to walk through a commercial quote end to end.

The Short Version

Solar quoting software sizes a system, models production, calculates incentives, and produces a proposal. In Australia the incentive step is where generic tools fall over. STCs, VEECs, and LGCs each have different eligibility, and getting the zone rating, the VEEC stacking, or the 100 kW threshold wrong shows up as a wrong number on the customer’s proposal. Decide whether your job mix is bill-first or roof-irradiance-first before you pick a tool, then check the incentive engine, tariff modelling, and proposal output against your actual quoting volume rather than a feature checklist.

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