To rate each solar company, we analyzed the data from our research and created review standards based on our findings. We evaluated each provider in six comparison categories: solar equipment and services, warranty and performance guarantees, brand reputation and certifications, financing options, industry experience, and state availability.
We rated each solar installer across 18 factors within these categories, each receiving a point value. The value was based on factors most important to homeowners looking for a solar provider. We established a 100-point scale for our scoring system with the categories outlined below:
Solar Equipment and Services
The solar equipment and services category carries one of the highest weights in our provider review. Solar equipment is essential to any solar system, with higher-quality equipment yielding the best results. We check each company’s catalog for diverse equipment offers and add-on accessories. Additional solar services, such as monitoring, help maintain system health, ensuring excellent energy production into the future.
Your solar equipment plays a major role in your system’s productivity and efficiency. Most solar providers offer traditional rooftop solar panels. We awarded additional points to installers, including advanced solar roofing, tiles, or shingles in their product catalog. A larger product selection gives homeowners more ways to customize their solar projects to fit their needs.
Beyond the solar panels themselves, additional equipment, such as solar storage and electric vehicle (EV) chargers, extend your system’s capabilities. We award points to solar providers offering these add-on options.
Solar companies often use in-house or third-party installers to complete their projects. In-house installers offer better quality control and communication, leading to a smoother process. With third-party installers, project updates and communication goes through one or more individuals. When researching each solar installer, we noted their installation process and team. Installers with in-house teams received higher points than companies outsourcing to third-party contractors.
Solar companies received additional points for including performance-tracking apps and monitoring services. These services offer insight into your solar system performance and early indications of technical or performance issues. Additional services, such as roofing and energy audits, were also included in our ratings and received added points if offered.
Warranty and Performance Guarantees
The success of a residential solar system depends on its workmanship and long-term protection. We evaluated each company based on individual system protections, such as workmanship warranties, manufacturer coverage, and panel performance guarantees. This category serves as the second highest weight in our company evaluation, tied with solar equipment.
Product or manufacturer warranties cover your solar equipment for any issues or defects caused by the manufacturer. Most high-quality solar panels include a 25-year product warranty to coincide with the typical panel life span of 25 years. We award more points for longer warranty coverage.
With labor or workmanship coverage, you receive protection for issues due to poor or faulty installation. This coverage comes directly from the installer and varies based on their coverage options. Ideally, you should match coverage with the panel’s estimated life span. We also award more points for longer workmanship coverage.
Production (or power) guarantees protect your panel’s linear performance. Over time, solar panels gradually drop in efficiency, which impacts their production. Most solar panel manufacturers include estimated efficiency degradation with their panel information.
However, some installers provide this added protection to back their products. If your panels fall below these estimated production levels, the company will repair, replace, or upgrade your panels. Some companies even provide monetary compensation for your lost energy production. This coverage is rare, so we awarded more points to any installers that provide it.
Roof Leak Coverage
Roof leak coverage offers additional protection against damage caused by the installation. Total coverage length varies between companies but is typically five to 20+ years. Since this is another rare coverage option, we award extra points to installers that provide this warranty coverage.
Brand Reputation and Professional Certifications
Brand reputation ties into a company’s trustworthiness and customer treatment. We checked each provider’s business history and industry experience. Our team conducts extensive brand reputation checks to evaluate customer reviews, review scores, pending lawsuits, and any outstanding negative behaviors. In addition, we review each company’s professional industry certifications.
We include BBB ratings in each solar company’s reputation review. Higher scores are awards for companies with “A” ratings and gradually drop for lower ratings. Companies designated with an F or No Rating (NR) receive no points.
We add additional points for solar installers with BBB accreditation. According to the BBB, having accreditation means that “BBB has determined that the business meets accreditation standards, which include a commitment to make a good faith effort to resolve any consumer complaints.” Businesses pay an additional fee for accreditation and ongoing monitoring for compliance and standards.
Average Review Scores
Along with BBB reviews, we weigh additional review site scores to get a clearer picture of customer experiences. We average scores from at least three review sites, such as Best Company, Google Reviews, Trustpilot, and Yelp. These scores are calculated on a five-star rating scale and awarded points based on their final average. Companies with average scores of 4.5 stars or higher receive more points and gradually scale downs, with 1.5 stars or lower receiving the lowest score.
In our research of each solar company, we conduct specific searches for any current legal issues that impact customer experience, trustworthiness, and public safety. We subtract points from any company with major pending or ongoing litigation or class action settlements.
Review Site Alerts
Many review sites will add alerts on company profiles to notify consumers of past or ongoing negative behaviors. This could include long-term customer support issues, poor or delayed installations, lawsuits, or any negative behavior that could impact current or future customers. We deduct points for any active alerts for a solar installer.
The North American Board of Certified Energy Practitioners® (NABCEP®) is one of the most well-respected and widely recognized renewable energy organizations in the United States. Companies that earn the organization’s official certification have taken the extra step to educate their installers on proper solar installations.
While NABCEP certification is not required for solar installers, it’s a testament to a company’s commitment to staying up-to-date on solar energy technology, installation standards, and overall ethics and professionalism. Our team awards additional points for NABCEP-certified installers.
We awarded higher scores to solar companies with multiple financing options. Some payment options, such as solar leases and power purchase agreements (PPAs), disqualify homeowners from cost-saving solar incentives, credits, and rebates. We included companies with these options to ensure all readers can find a provider that fits their needs and budget. However, we did deduct points for companies that only have leases or PPAs, since they offer the least financial benefits.
In addition, we awarded higher points to installers that provide in-house financing options versus third-party lenders. Internal financing options typically provide more flexible rates and payment options than an outside lender.
We looked for companies with larger service areas and resources to serve their customers adequately. We also included smaller solar installers that specialize in regional installations. Typically, regional installers have better knowledge of their specific region than nationwide installers. We want to ensure that our readers have a diverse selection of solar providers for most areas.