Our Rating Methodology
The This Old House Reviews Team is committed to providing comprehensive and unbiased reviews to our readers. This means earning your trust through transparent reviews and having the data to back up our ratings and recommendations. Our rating system for solar panel companies and installers is on a 100-point scale based on five factors:
- Payment options (40 points): Options include purchase, loan, lease, and Power Purchase Agreements (PPAs). Companies receive points for each of those four options it provides.
- Solar services (30 points): Does the company provide in-house installation of solar panels and battery backups? Can the company also monitor energy production and perform energy-efficiency audits to ensure system performance. The more options available, the higher the score.
- Warranty options (10 points): The success of a residential solar system depends on the workmanship, performance guarantees, and length of product coverage. We score solar companies based on the number of warranty options available. The more warranties a solar company offers, the higher the score it receives.
- State Availability (10 points): We award the most points to solar companies with the broadest service area and state availability.
- Reputation (10 points): We factor in how the Business Better Bureau (BBB) scores each company. We deduct points for any alerts or pending lawsuits.
