In short: A winning commercial solar proposal template runs through nine sections in a fixed order: an executive summary with one headline number, the current bill decomposed into energy, demand, network and daily charges, the consumption profile behind the model, the system itself (size, faces, tilt and azimuth, inverter, battery), a solar-only vs solar+battery comparison, every financial assumption listed explicitly, incentives itemised line by line, payback/NPV/IRR with a sensitivity table, and risks with a validity date. Skip any one of these and a CFO or facilities manager has a reason to stall the sign-off rather than approve it.
The Commercial Solar Proposal Checklist
Before the section-by-section walkthrough, here is the whole thing on one screen. Use it to audit a proposal you have already sent, or a template you are about to build.
| Section | Why it matters | Common mistake |
|---|---|---|
| Executive summary | The only page most decision-makers actually read closely | Burying the headline number on page 4 |
| Current bill, decomposed | Shows the reader exactly where the savings come from | One lump “annual spend” figure with no breakdown |
| Consumption profile | Proves the model is built on this site’s real load, not a template | No mention of whether it’s interval data or an estimate |
| The system | Lets an engineer or facilities manager sanity-check the design | kW only, no faces, tilt, inverter or weather source stated |
| Solar-only vs solar+battery | Battery is a separate capital decision and should read as one | Battery bundled in with no standalone case shown |
| Financial assumptions | The single biggest source of quote-to-quote distrust | Escalation, degradation and discount rate left implicit |
| Incentives, itemised | Rebates expire and change; a lump figure ages badly | STCs and battery incentives folded into “system cost” |
| Payback, NPV, IRR + sensitivity | One number invites one question: “what if you’re wrong?” | A single best-case payback figure with no downside case |
| Risks, exclusions, next steps, validity | Protects both parties and forces a decision date | No expiry, so the quote is still “live” a year later |
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Executive Summary and the Current Bill, Decomposed
Executive summary. One page, one headline number: payback period, or net earnings over the analysis horizon, whichever the reader cares about more. State the system size, the net investment after incentives, and the recommended action. Everything else in the document supports this page; nothing above it.
The current bill, decomposed. Do not summarise the site’s spend as a single annual number. Break it into the same components the bill itself uses (energy usage, demand charges, network (DUOS/TUOS) charges and daily/fixed charges) and show which of those solar and battery actually reduce. Energy usage falls as production offsets grid draw during daylight; demand charges fall only if the battery is sized and dispatched to shave the peak; daily charges do not move at all, because they are billed whether the site imports one kilowatt-hour or a million. A reader who can see this breakdown understands why the savings estimate is what it is, rather than taking a number on faith. For the full anatomy of an Australian commercial bill, see how to read a commercial electricity bill, and for the demand-charge mechanics specifically, demand charges and solar.
The Consumption Profile and the System
Consumption profile. State plainly how the load was derived: a full year of interval meter data uploaded by the customer, a partial year extrapolated to a full year, or a template profile built for the site’s business type when no interval data exists. This one sentence is doing more credibility work than any chart in the document, because it tells the reader whether the hourly simulation behind the numbers is running against their real building or an assumption.
The system. State the total kW, the roof faces it sits on with tilt and azimuth for each (Amperage authors roof faces rather than individual panel placement, which is the right level of detail for a proposal; the customer needs to see the plan is site-specific, not a panel-by-panel layout), the inverter, and the battery’s power and energy rating in kW and kWh separately. Then state the annual production estimate and, critically, where the weather data behind it came from: a TMY or EPW dataset for the nearest matched location, not a national average. A facilities manager who has been burned by an irradiance-map estimate before will specifically look for this line.
Solar-Only vs Solar+Battery
Batteries are a separate capital decision layered on top of solar, and a proposal that bundles them without a standalone comparison makes that decision invisible. Show both cases side by side: solar-only capex, payback and annual savings, then solar+battery with the same three numbers, so the incremental battery cost buys a visible, calculable incremental return, typically demand-charge reduction and higher self-consumption from shifting production into evening peak load, from an hourly dispatch simulation against the site’s actual load rather than a flat percentage assumption. This is exactly the comparison an Analysis project is built to produce before a proposal is even started.
Financial Model Assumptions: List Them, Don’t Bury Them
This is where trust is won or lost. Every commercial solar payback figure rests on assumptions the reader cannot see unless the proposal states them, and a spreadsheet that hides them is the single biggest reason experienced buyers discount a quote on sight.
Tariff escalation. State the annual rate applied from year 2 onward. Year 1 should carry no escalation (it is the customer’s actual current bill, unescalated) with the rate compounding from year 2. Some quoting spreadsheets escalate year 1 as well because their baseline is a historical bill rather than the current one; if a competing quote’s year-1 savings figure looks unusually high, check which convention it used.
Degradation. State the annual panel output decline (a typical range is around 0.3–0.5% per year) so the production curve in year 15 is visibly lower than year 1, not flat.
Replacement year. Inverters and batteries do not last the full analysis horizon. State the assumed inverter replacement year and battery replacement year (tied to its warranty, or a conservative default when the warranty is unspecified) and the assumed cost, at today’s prices. Full mechanics are in battery & inverter replacement costs.
O&M. State the assumed annual operations and maintenance cost, even if it is small, an omitted line item is not the same as a zero-cost one.
Discount rate. State the rate used to compute NPV. A reader comparing this proposal to their own hurdle rate needs to know what rate produced the NPV figure on the page, not just the figure itself. For the full modelling chain behind every one of these levers (weather matching, production modelling, battery dispatch and the financial model itself), see how the modelling works.
Incentives, Itemised
List each scheme the site qualifies for as its own line, not folded into “system cost”: Small-scale Technology Certificates (STCs) for the solar, Large-scale Generation Certificates (LGCs) on any capacity above the STC ceiling (1 MW of site capacity for installs from 1 October 2026, 100 kW before), state schemes where relevant (VEECs in Victoria, NESC and PDRS in NSW), and battery incentives (bSTCs, the industry term for battery STCs under the Cheaper Home Batteries program) where the site qualifies. Each of these has its own eligibility rule, its own certificate price, and in some cases its own expiry date, so a single “incentives: $X” line hides exactly the information a reader needs to check the number is current. The full current state of every scheme, with stacking rules, is on the solar incentives hub.
Payback, NPV, IRR + a Sensitivity Table
A single payback number invites exactly one follow-up question: “what if you’re wrong?” A sensitivity table answers it before it is asked. Take a worked example: a 200 kW solar+battery system with a net investment of $290,000 after incentives and assumed year-1 savings of $58,000 (energy plus demand reduction, unescalated, on the site’s current bill). At a 3% annual tariff escalation from year 2 and a 7% discount rate, cumulative savings pass $290,000 partway through year 5 (a payback of roughly 4.7 years), and the 10-year NPV comes to about $169,000, for a 10-year IRR of roughly 17.8%.
The sensitivity table shows what moves that number:
| Scenario | Payback | 10-year NPV @ 7% |
|---|---|---|
| Base case: 3% escalation, full production | ~4.7 years | ~$169,000 |
| 0% tariff escalation | ~5.0 years | ~$117,000 |
| Production 10% lower than modelled | ~5.2 years | ~$123,000 |
Even in the softest case here, the investment still pays back inside six years and still returns a positive NPV. That is the point of the exercise: a sensitivity table that survives a stress test builds more trust than a single optimistic headline figure ever does, because it shows the proposal was tested against the questions a careful buyer will actually ask.
Risks, Exclusions, Next Steps and Validity
Risks and exclusions. State what the price does not cover (switchboard upgrades, structural roof work, DNSP connection approval delays) and the key assumption risks: that consumption stays roughly in line with the historical profile, that the site’s tariff structure does not change materially, and that incentive values are locked at time of acceptance rather than time of installation where that distinction matters.
Next steps and validity. Name the next action (site inspection, contract signing, deposit) and put an expiry date on the proposal. Incentive certificate prices and equipment costs move; a quote with no validity date is quietly wrong the day certificate prices move against it, and it gives the customer no reason to decide this month rather than next.
Analysis Deck vs Proposal Export: Two Different Documents
Not every one of these sections belongs in every document you send. An Analysis project exports as a PPTX deck built to get sizing agreed; solar and battery scenarios side by side, a sizing matrix, enough of the financial case to justify moving forward, but not a line-by-line tariff build. A Proposal project exports the branded proposal as an editable A4 PowerPoint, built once the size is settled: roof faces, detailed tariff pricing, and every section above in full. Sending the deck when the customer expects the proposal (or the reverse) is a common source of “this doesn’t look like what I asked for” friction that has nothing to do with the numbers being wrong.
Where to Go From Here
Every one of these numbers only holds up if the model behind it is sound. The escalation, degradation, replacement and discount-rate levers described above are documented in full at how the modelling works and replacement costs. Amperage builds this exact structure (bill breakdown, consumption profile, sizing comparison, itemised incentives, and the payback/NPV/IRR sensitivity view) automatically from a bill and a consumption profile, so the proposal a customer receives is the same model you used to size the job, not a separate document assembled by hand afterward.
How to read the proposal output: the full model behind the proposal →