Most solar proposals lead with the wrong number. A rupee-per-watt price or a headline capacity figure tells you almost nothing about whether the investment makes financial sense. A proposal built to survive a CFO's review leads with five measures instead, and is explicit about the assumptions behind each one.
The five measures
IRR, the annualised return the project generates, modelled on realistic assumptions for investment, generation, tariff escalation, finance, tax and operating costs.
Simple payback, how long before cumulative savings recover the investment, compared across CAPEX, OPEX / RESCO, captive and lease structures.
NPV, the project's value in today's rupees once future cash flows are discounted, which is what lets different structures be compared fairly.
Depreciation and tax impact, which can materially change after-tax cash flow for an owned asset and should be assessed against your own tax position.
Energy cost reduction, the true landed cost of grid power, on-site solar, open access, captive supply and storage compared side by side rather than solar in isolation.
The assumptions behind each
Every one of those five measures is only as good as the generation estimate underneath it. Ask what degradation curve the model assumes, what tariff escalation it's pricing in, and, most importantly, how the generation figure was derived. A model built on a genuine load analysis and site-specific simulation, not a regional average, is the difference between a plant that tracks its estimate and one that quietly underperforms for years.
Red flags in a weak proposal
If a proposal doesn't show IRR and payback explicitly, that's a flag. If there's no depreciation schedule, that's a flag. And if there's no long-term O&M plan beyond commissioning, that's the biggest one, it's how solar assets end up orphaned, generating below their modelled output with nobody accountable for the gap.
What we build instead
Every Polaris proposal starts from a decision-grade techno-commercial comparison, IRR, payback, depreciation and cash flow, so management can see the options clearly before capital is committed. The same thinking carries into monitoring, O&M and performance support after commissioning.