How to evaluate multiple solar proposals
Comparing quotes requires looking beyond the headline price to equipment specs, production estimates, warranties, and installer reputation. A structured comparison helps identify best value rather than just lowest cost.
Comparison checklist:
- System size and production estimate: Ensure all quotes are for the same system capacity and use similar assumptions for production.
- Equipment details: Compare panel models, inverter types, and racking systems with datasheets and warranties.
- Total cost and incentives: Verify what’s included—permitting, interconnection, inspections, and rebates.
- Financing and payment terms: Compare cash price, loans, leases, and power purchase agreements (PPAs).
- Warranties and maintenance: Look at panel, inverter, and workmanship warranties and who handles service.
- Installer qualifications: Check licenses, certifications, local references, and insurance.
- Performance guarantees: Some installers offer production guarantees that back estimated output.
Practical tips
- Ask for itemized quotes to compare apples to apples.
- Request references and visit local installations if possible.
- Be wary of extremely low bids that omit essential components or use unproven equipment.
A careful comparison ensures you select an installer and system that meet performance, reliability, and financial goals.