Step 1: Verify Licensing and Certification
Every solar installer must hold a valid state electrical contractor's license. The gold standard beyond state licensing is NABCEP PV Installation Professional certification. Verify any installer's NABCEP status in the public directory.
NABCEP-certified installers pass exams covering NEC electrical code, system design, battery storage, and safety. Only about 7,000 professionals hold this in the US. It is not mandatory, but its presence is a strong quality signal.
7 Questions to Ask Every Solar Installer
| # | Question | Why It Matters | Red Flag Answer |
|---|---|---|---|
| 1 | What panel brand and model will you install? | Tier-1 brands (REC, Panasonic, Maxeon, Q CELLS) have lower defect rates. Off-brand panels may not last 25 years. | "We use quality panels" without specifying brand |
| 2 | What inverter type — string, micro, or power optimizers? | Microinverters (Enphase) handle shading better and come with 25-yr warranties vs. 10–12 yr for string inverters. | No explanation of tradeoffs |
| 3 | What is the estimated annual production in kWh? | Lets you calculate real payback and catch overly optimistic projections. Should match PVGIS data for your location. | No written production estimate |
| 4 | Who pulls permits and handles utility interconnection? | Your installer should handle all permits. Asking you to pull permits yourself is a major red flag. | "You'll need to handle permits" |
| 5 | What does the workmanship warranty cover and how long? | Equipment warranties cover hardware defects. Workmanship covers installation defects. Standard is 10 years minimum. | Less than 5-year workmanship warranty |
| 6 | How many systems have you installed in my county? | Local permitting experience matters. Unfamiliar installers cause multi-month delays. | Evasive or "we install everywhere" |
| 7 | Are you the installing company or a broker? | Some "installers" sell leads to subcontractors, creating warranty accountability gaps. | Evasive answer about who actually installs |
National vs. Local Installers
| Factor | National Companies | Local Installers |
|---|---|---|
| Price | Often 10–20% higher (marketing costs) | Generally more competitive |
| Financing | Broad — loans, leases, PPAs | Loans typical; fewer lease/PPA options |
| Installation crew | May subcontract to local crews | Direct employees, more consistent quality |
| Warranty response | National support line; slow in some regions | Faster local service calls |
| Local permit knowledge | Variable by region | Deep local expertise |
| Risk if company closes | Higher — many solar firms have gone bankrupt | Lower — established locals tend to persist |
Red Flags and Common Scams
Solar fraud has increased alongside industry growth. Common schemes include door-to-door sales with high-pressure same-day deadlines, inflated system sizes to maximize loan amounts, and "zero electric bill" guarantees written nowhere in the contract.
Verify any installer's license with your state contractor board. The US Department of Energy's Homeowner Guide to Going Solar and the SEIA consumer protection page both provide current vetting guidance.
Frequently Asked Questions
What is NABCEP certification for solar installers?
How many solar quotes should I get?
What should a solar contract include?
Are national solar companies or local installers better?
What are common solar installer red flags?
Key sources:
• NABCEP — Find a Certified Professional
• US DOE — Homeowner Guide to Going Solar
Know Your System Size Before Talking to Installers
Use our free calculator to get a baseline system size and cost estimate — so you can evaluate quotes from an informed position.