Solar quotes are easy to get and hard to trust. Every EPC will tell you your roof is perfect — they're selling panels. "Bankable" means something stricter: a design and financial model solid enough that a lender, a board, or a skeptical CFO signs off. That standard is decided by five checks, and most quotes skip at least two of them.
Check 1 — Load match: when do you actually use power?
Solar produces on a bell curve centered on midday. The single biggest driver of your return is how much of that production you consume on-site the instant it's generated, because self-consumed energy offsets your full retail tariff while exported energy earns far less.
- Great match: daytime-heavy operations — manufacturing day shifts, cold storage (compressors fight the afternoon heat), malls, offices, schools.
- Needs care: night-shifted plants, facilities closed weekends (that's ~30% of annual production earning export rates, not retail rates).
Any quote built on monthly bills alone is guessing at this. Interval data — your consumption every 15 or 30 minutes — is what turns the guess into a number.
Check 2 — The structure: the check nobody wants to pay for
Panels, rails, and ballast add roughly 12–20 kg/m² (more where wind-uplift design in typhoon regions demands heavier anchorage). Purlin-and-sheet industrial roofs in the Philippines were rarely designed with that reserve. A structural assessment by a civil/structural engineer is a small line item; discovering mid-installation that your purlins need reinforcement is not. If a proposal doesn't mention structural verification, that cost hasn't vanished — it's waiting for you.
Check 3 — Tariff reality, not brochure math
The payback in a sales deck is usually computed against your average blended rate. Your actual avoided cost depends on the structure of your tariff — generation, transmission, distribution charges, demand charges — and on which parts solar actually displaces. Two facilities with identical bills can see materially different solar economics. And if you're eyeing net metering: programs have capacity caps and export compensation well below retail — the model must price exports honestly, not at the retail rate.
Check 4 — Interconnection and paperwork lead time
Distribution-utility approval, net-metering applications where applicable, permits, and (above certain sizes) additional regulatory steps all carry lead times measured in months, not days. None of this kills a project; all of it kills a schedule that ignored it. A bankable proposal shows the interconnection pathway and its timeline explicitly.
Check 5 — The sizing mistake in most quotes
Here's the one that costs the most and gets caught the least: EPCs size systems against your current load — waste included.
Fix the efficiency first, and the "right" solar system is often 15–20% smaller, cheaper, and faster to pay back.
If your facility is about to cut consumption 20% through an efficiency program (and most facilities that have never been audited can), a system sized today is oversized tomorrow — capex spent to generate energy you no longer need, at export rates. This is why we refuse to design solar before the audit: the array should be sized against the corrected load. In our cold-storage engagement, that sequencing alone cut the array 18% versus the EPC's original quote — with a faster payback (the case).
What a bankable package contains
- Yield simulation from hourly irradiance data with explicit loss assumptions (soiling, temperature, degradation, availability)
- String design and single-line diagram to IEC 62446 / NEC 690 / PEC — buildable without redesign
- Structural verification, or a defined scope for it
- Financial model: LCOE, IRR, NPV, and sensitivity runs on tariff escalation and self-consumption share
- Interconnection pathway with realistic timeline
- An M&V plan, so year-one performance is provable against the model — that's what makes it bankable rather than hopeful
The cheap way to find out
Our Recon tier includes a solar feasibility snapshot — usable roof area, indicative yield, and IRR from your actual data — inside the two-week remote analysis. If the snapshot says the economics aren't there, you've spent very little to avoid a very expensive mistake. If it says they are, Blueprint turns it into the bankable package your board and bank will actually sign.