A commercial solar proposal must be usable by the people evaluating the project: finance, facilities, procurement, site owners and other decision-makers as applicable. Give them a traceable design and energy basis, project-specific economics, responsibilities, open dependencies and a clear next decision. Do not substitute an attractive return figure for the assumptions behind it.
SurgePV publishes this guide and sells solar design and proposal software. The recommendations below are an editorial preparation framework, not evidence of measured conversion uplift, financing approval or project performance.
Map the buyer’s decision before building the document
Commercial projects can have multiple reviewers and an investment or operating-budget decision. Residential customers can also require detailed financial and technical explanations. Neither audience has a universal system size, contract value, number of decision-makers or sales-cycle duration.
Identify the signatory, technical reviewers, site/property rights, capital or procurement process, utility relationship and decision objective. Ask whether the customer prioritizes ownership, predictable obligations, energy savings, emissions reporting or another documented goal. These can require different proposal evidence.
Five qualification questions
- Who owns or controls the building, roof and meter, and what consents are needed?
- What consumption and tariff evidence can the customer share, over which periods?
- Who decides, who reviews and who can authorize the next project stage?
- Which ownership and payment arrangements are available for this customer and location?
- What actual deadline or operational dependency drives the decision?
A tenant or a customer without capital approval is not automatically disqualified. Record the required consent or decision route before investing in further work. Tax treatment belongs with the customer’s qualified advisers, not a salesperson’s assumed “tax appetite.”
Use seven stages without inventing a calendar
| Stage | Useful evidence or action | Condition to resolve |
|---|---|---|
| Qualification | Site rights, objectives, decision roles and next authorized step | Missing authority, access or commercial fit |
| Data collection | Consumption, tariff, site and equipment evidence | Incomplete periods or unverified meter boundary |
| Site assessment | Appropriate technical/site investigations and records | Roof, electrical, access or other unresolved constraints |
| Preliminary design | Identified layout, equipment and energy-model revision | Provisional inputs and review limitations |
| Proposal preparation/presentation | Matched technical, commercial and financial assumptions | Contradictory versions or unsupported claims |
| Customer diligence | Responses assigned to the appropriate reviewers | Unresolved finance, property, utility or technical questions |
| Agreement and delivery handoff | Accepted scope, terms and remaining prerequisites | Expired offers or requirements not transferred to delivery |
Stages may overlap or repeat. Establish dates from actual dependencies and team capacity, not generic three-to-nine-month claims. A proposal can be sent for review before every detail is resolved if its preliminary scope and open issues are unmistakable.
Gather data appropriate to the analysis
Use enough utility history to represent the chosen analysis period and seasonal behavior. Record account/meter boundaries, billing periods, import/export measurements and material operational changes. Do not assume a single bill describes annual use.
Obtain the actual tariff, including time periods, demand charges, ratchets, fixed charges, export rules and relevant riders. Obtain interval data at the granularity the proposed demand analysis requires; a universal fifteen-minute prescription is inappropriate when billing rules or available data differ.
For site work, identify the layout/survey references, roof documents, service equipment information, ownership/lease constraints, warranty terms and required competent assessments. A sales observation is not structural or electrical approval.
Build the financial model from defined cash flows
Keep energy, billing and financing models separate enough that reviewers can trace each step. Generation in kWh is not automatically avoided retail expenditure. Self-consumption, export allocation, curtailment and utility charges determine the energy/bill relationship.
The DOE utility-rate guide distinguishes consumption and demand-charge structures, including time-dependent charges. This supports using the actual rate structure. It does not establish a demand reduction for a particular site. Annual kWh multiplied by a blended rate cannot validate demand-charge savings.
Explain the metrics and their limits
| Metric | Interpretation | Required disclosure |
|---|---|---|
| NPV | Present value of the modeled net cash flows at a declared discount rate | Perspective, period, timing and discount-rate basis |
| IRR | Rate at which the specified cash-flow NPV is zero, if a meaningful solution exists | Project versus equity perspective, financing and any multiple/no-solution limitation |
| Simple payback | When cumulative undiscounted modeled net benefits recover the stated outlay | Included costs, timing and whether recovery occurs within the period |
| Discounted payback | Recovery based on discounted modeled cash flows | Discount rate and unrecovered amount if no recovery occurs |
| Annual net cash flow | Modeled receipts/benefits less the relevant payments in that year | Utility, operating, finance and tax components included or excluded |
There is no universal good IRR, discount rate, payback target or positive first-year financed result. Ask the customer’s reviewers for the relevant evaluation criteria. NPV above zero supports the modeled case at its stated assumptions; it does not prove it beats every alternative or will achieve the modeled result.
Source the assumptions rather than label defaults conservative
Record the weather/resource data, shading, system losses, equipment, degradation assumptions, tariff, export treatment, operating costs, replacement events, financing, taxes and chosen analysis period. State who supplied each input and when it was verified.
Use supplier/maintenance evidence and project-specific analysis for cost and replacement inputs. Use a declared tariff scenario for future rate changes; do not call any fixed escalation range universally conservative. A public cost benchmark is context, not a replacement for the same-scope project quote.
A bounded worked example, without assumed tax relief
Assume a hypothetical 500 kW DC project quoted at $1.85 per DC watt. Its quoted capital amount is 500,000 W × $1.85/W = $925,000. The following simplified annual calculation assumes every generated kWh receives the stated value. It omits operating costs, degradation, financing, taxes, replacements, fixed/demand charges and discounting. These are scenario inputs, not market forecasts or an investment recommendation.
| Scenario | Assumed generation | Assumed uniform energy value | Simplified annual gross benefit | Capital/gross-benefit ratio |
|---|---|---|---|---|
| Lower | 615,000 kWh | $0.12/kWh | $73,800 | 12.53 years |
| Middle | 650,000 kWh | $0.13/kWh | $84,500 | 10.95 years |
| Higher | 680,000 kWh | $0.14/kWh | $95,200 | 9.72 years |
The final column is not project payback: omitted costs and changing annual results matter. No IRR can be inferred from this table without a complete timed cash-flow series. For an actual site, separate self-used and exported energy and run the applicable tariff calculation.
Current U.S. tax eligibility needs separate review
As checked September 30, 2026, IRS Notice 2025-42 explains termination provisions affecting applicable solar/wind facilities placed in service after December 31, 2027 when construction begins after July 4, 2026. The construction-start test and other eligibility requirements need qualified project-specific assessment. Do not automatically subtract a commercial credit merely because wage conditions are discussed.
Use the IRS clean electricity investment credit information and applicable guidance with the customer’s adviser. Record the eligible taxpayer, basis, rate, other requirements and timing only when established. Do not substitute the homeowner credit for commercial treatment or count a modeled tax reduction as cash already received.
P50/P90 are not standard sales haircuts
If the project needs probabilistic energy estimates, name the modeled period, output boundary and uncertainty scope. An exceedance estimate is not a production guarantee; single-year and multi-year uncertainty are different. Obtain the financier’s actual evidence requirements rather than prescribe P90 for every loan or assume a fixed percentage gap. See the P50/P90 explanation.
Compare five structures by actual customer obligations
| Structure | What to explain | What not to assume |
|---|---|---|
| Cash purchase | Purchase scope, timing, ownership and ongoing costs | Highest value for every customer or automatically usable tax benefits |
| Loan-financed purchase | Financed price, principal, fees, debt schedule, security and covenants | Universal DSCR, fixed monthly payment or optimum term |
| Lease | Equipment-use payments, ownership, service, transfer and end-of-term terms | Automatically off-balance-sheet, zero upfront cost or uniform maintenance responsibility |
| PPA | Contracted energy boundary/rate, escalation, term, export allocation and remedies | Rate always below utility cost or all purchased energy avoids retail imports |
| Specialist tax-equity arrangement | Adviser-defined parties, allocations, cash flows and obligations | Standard costs, minimum project size or automatic host benefit |
Compare only actually available offers on a common design and analysis basis. Specialist structures require appropriate advisers. The narrower cash, loan, lease and PPA sales comparison provides a conversation worksheet. Do not prescribe two offers if the relevant alternative is unavailable or unsuitable.
Ten proposal sections to adapt
- Executive summary: project objective, design basis, decision requested and key economics with their limitations.
- Site and system design: identified layout, scope, equipment and unresolved constraints.
- Energy estimate: resource, shading/loss treatment, period, boundary and uncertainty where assessed.
- Financial analysis: timed cash flows, metric definitions, scenarios and costs included/excluded.
- Ownership/payment options: actual terms and comparable assumptions.
- Equipment and service details: sourced specifications, warranty and responsibility allocation.
- Evidence of capability: only documented credentials and genuine references shared with permission.
- Project dependencies: permits, utility processes, site access, schedule assumptions and responsible parties.
- Terms/assumptions: quote validity, scope/exclusions, change route and input sources.
- Next decision: named participants, required evidence and an agreed next action.
Provide a concise executive summary and accessible supporting detail. No fixed page count or reading order fits every procurement process. Offer a walkthrough where useful, but sending a review document without a meeting is not proof it will go unread.
Eight checks before releasing the proposal
| Check | Review action |
|---|---|
| Economics and project objective agree | Identify the customer’s decision criteria, not a generic CFO stereotype |
| Options are comparable | Reconcile design, scope, period and energy basis |
| Energy claims are labeled | Identify modeled versus measured results and uncertainty scope |
| Demand and energy value are separated | Validate the tariff and interval/billing calculation |
| Escalation is declared | Cite the scenario basis and show sensitivities |
| Readers can inspect assumptions | Supply supporting records and answer routes |
| Next action is owned | Record the actual requested decision and participants |
| Revision status is current | Reconcile layout, energy, finance and proposal references |
These are diagnostic checks, not proven causes of lost deals. Observe your own returns, elapsed stages and correction work before claiming a turnaround or conversion improvement. Set a service target from capacity and project needs, not an unsupported universal deadline.
Keep revision and software claims testable
A design change can affect production, costs, savings and the customer document. Compare the old and new accepted references, identify affected outputs, rerun the relevant models and review the issued successor. Preserve what the customer previously received.
Evaluate SurgePV proposal preparation, design outputs and financial workflow against these needs. In a demo, ask which calculations and exports are supported, what updates after a change, and which reconciliation/review steps remain manual. Do not infer native CRM, tax eligibility certification, lender acceptance or zero-step propagation.
Copy-ready proposal release record
| Field | Entry |
|---|---|
| Project/proposal ID, revision, date and recipients | |
| Governing design/equipment/energy references | |
| Financial model version, perspective and analysis period | |
| Quote/finance provider references and expiry | |
| Tariff/export/incentive sources and confirmation status | |
| Scenario differences and sensitivity results | |
| Site, authority, utility and customer prerequisites | |
| Technical/commercial/financial reviewers and their scopes | |
| Open question, decision owner and due point | |
| Authorized issue state, prior version and next action |
Use the record to support a reconstructable customer decision. A signed proposal does not itself establish engineering approval, a permit or utility permission to operate.
Frequently Asked Questions
What should be included in a commercial solar proposal?
Include the project objective, identified design and equipment, energy estimate, timed financial assumptions, relevant ownership/payment options, scope, responsibilities, dependencies and next decision. Supply sources and limitations so reviewers can reconstruct the case; no fixed format guarantees acceptance.
How do you price a commercial solar project?
Build a project-specific quote from the accepted scope and current cost evidence, then model customer cash flows separately. State currency, capacity basis and included work when comparing prices per watt. Tariffs, financing, operating costs and tax treatment require their own sourced assumptions; no universal analysis period applies.
What is a good IRR for commercial solar?
There is no universal target. Compare the correctly defined project or equity IRR with the customer’s evaluation criteria and assess NPV, cash timing and risks alongside it. State the cash-flow perspective and assumptions; some cash-flow patterns have no meaningful IRR or more than one solution.
How long does a commercial solar sales cycle take?
It depends on the customer decision process, site rights, data, technical review, financing, utility and other dependencies. Use observed stages and actual review calendars to plan the next decision. A proposal turnaround target is a team planning choice, not a guaranteed total sales-cycle duration.
What is the difference between a lease and a PPA for commercial solar?
A lease generally pays for equipment use; a PPA generally pays for contracted energy. Actual ownership, payment changes, maintenance, export allocation, transfer and end-of-term obligations depend on the agreement. Neither is automatically zero-cost, simpler, cheaper or risk-free for every customer.
How do you write a winning commercial solar proposal?
Prepare a reviewable project case: relevant customer objective, consistent design and energy basis, sourced financial assumptions, realistic dependencies and an owned next decision. Explain available options and unresolved questions. These practices support evaluation but do not establish measured conversion uplift or guarantee a signed contract.
Where this fits
This article is part of SurgePV's Commercial Solar hub, which works through the topic from first principles to the decisions a project team actually has to make.
