How to Evaluate a Solar EPC: A Due-Diligence Checklist

Most solar disputes don't happen at the point of sale — they happen years later, when a panel underperforms or an inverter fails and the EPC is no longer reachable. Evaluating an EPC properly upfront is the single highest-leverage thing a buyer can do.

1. Verify component sourcing

Ask for the specific module and inverter brands and model numbers in writing — not just "Tier-1 panels." Cross-check that modules are on the ALMM (Approved List of Models and Manufacturers) if the project requires it. Cheaper, unlisted components are a common way quotes get padded with hidden margin.

2. Check track record, not just years in business

A company registered for ten years but installing for two tells a different story than one with ten years of installation history. Ask for:

• A list of completed projects in your city or region.
• At least two references you can independently contact.
• Evidence of net-metering applications successfully processed with your local discom.

3. Read the workmanship warranty carefully

Module and inverter warranties come from manufacturers, but the installation (workmanship) warranty comes from the EPC itself. Ask:

• What does the workmanship warranty cover, and for how long?
• What happens if the EPC ceases operations — is the warranty transferable or insured?

4. Understand the O&M plan

Get the O&M scope in writing: cleaning frequency, monitoring access, and response time for fault resolution. A system without a clear O&M plan tends to underperform silently — output drops 10-20% from soiling and nobody notices until the next bill arrives.

5. Compare at least three quotes on equal terms

Normalize quotes by capacity (₹/watt), not just total price — EPCs sometimes quote smaller systems to appear cheaper. Ask each EPC for an identical specification sheet so the comparison is apples-to-apples.

6. Confirm structural and safety compliance

For rooftop installs, confirm the EPC has assessed roof load capacity and will provide earthing, lightning protection, and fire-safety compliant wiring — not just panels and an inverter.

7. Clarify payment milestones

A reasonable payment schedule ties disbursement to verifiable milestones — material delivery, installation completion, commissioning, and net-metering approval — rather than a large upfront payment before work begins.

The takeaway

The cheapest quote is rarely the best long-term deal if it comes from an EPC that cuts corners on components, warranty enforcement, or O&M. Use our EPC Directory to compare installers by city and focus area, and run every shortlisted EPC through this checklist before signing.