The WattBot Trust Score
What it measures and why
"But who should I go with?"
I've spoken to over a thousand homeowners about adding solar and batteries to their home. Going solar is a no-brainer. The technology works. The savings are real. Choosing an installer shouldn't be the hard part. But it is.
We designed the Trust Score to fix this. You are 10x less likely to make a bad decision when you use the WattBot Trust Score.
Dhanur Grandhi CEO, WattBot
The problem with five stars
Rating Inflation. 81% of all solar reviews are five-star. Three out of four solar installers show up as "top-rated", with 4.5 stars or higher. When everyone looks excellent, stars are not useful.
Honeymoon Reviews. An overwhelming majority of reviews are posted within weeks of getting their system installed. These reviews bury feedback from a smaller group of customers who've been running their system for over a year, seeing real bills, and finding out whether the company stands behind its work. Those customers are 3x more likely to report a negative experience.
Volume Bias. When people compare installers, they gravitate toward the one with the most reviews. The bad actors disproportionately accumulate reviews, which means sorting by "most reviewed" increases your chance of working with a terrible company.
When you compare two five-star installers and pick the one with more reviews, there's a 1 in 10 chance you end up with a bad one. With the Trust Score, 1 in 100.
What is the Trust Score?
The Trust Score is a number from 1 to 100 that measures how trustworthy a solar installer is, based on real customer experiences over time.
These companies install solar panels, battery systems, and increasingly other home energy equipment. The Trust Score evaluates the full scope of what they do.
We evaluate every company through four lenses:
| Lens | What it captures |
|---|---|
| Review credibility | Are the reviews themselves trustworthy? |
| Reviewer authority | Does the reviewer have real experience with this company? |
| Work quality | What do customers say about the actual work? |
| Company character | Does the company's broader track record hold up? |
One principle runs through the entire methodology: signals that indicate risk can only lower a score, never boost it. No positive signal washes away a red flag. Penalties compound. This makes the Trust Score resistant to gaming and is explained further in the Company Character section below.
We score 20,000+ companies across 80,000+ local listings, producing over 130 million individual evaluations. Every review on every platform is analyzed. Not sampled. Not averaged. Analyzed.
How we weight reviews
Not all reviews carry the same weight. Consider two five-star reviews of the same company:
"We've had our system for two years now. Production has exceeded the estimate every month. When our inverter threw an error last spring, they had a tech out within three days and covered it under warranty. The crew was professional during installation, they even fixed a patch of flashing they noticed was lifting. Highly recommend."
"Great company! Very professional. Looking forward to getting our panels installed."
Both are five-star reviews. In our system, they carry very different weight. Here is what we adjust for:
Substance. Specific, descriptive content carries more weight than vague praise or reviews with no text.
Fairness. We don't penalize a company for things outside its control. Permit delays happen. Utility interconnection is slow. But a company that went silent during a three-month delay is accountable for the silence. Communication failure is the single most common reason a negative review counts against a company.
Recency. Recent reviews carry more weight than older ones. But a six-year-old review that describes a warranty dispute in detail still matters more than a five-star review posted last week with no text.
Customer vs. shopper. Did this person hire the company, or just get a quote? Shoppers can describe the sales process. Customers who completed an installation can describe the full experience.
Tenure. Only about 10% of solar reviews come from customers who have lived with their system for more than a year. We weight those reviews heavily. The ownership experience is what you're buying when you go solar. No honeymoon review can tell you what that will be.
Work quality
We read what customers say about the work itself and evaluate it across five dimensions.
| Dimension | The question | What we evaluate |
|---|---|---|
| Sales conduct | How did the sales team treat you? | Honesty, pressure tactics, clarity on pricing and financing. Whether promises made during the sale held up over time. |
| Workmanship | How well was the work performed? | Quality of the on-site installation. Whether solar panels, wiring, and battery systems were installed correctly and built to last. |
| Value | Was it worth the money? | Fairness of pricing and financing. Whether projected savings matched what the customer actually experienced. |
| Post-sale support | How did they support you after? | Responsiveness to problems. Whether warranties were honored. Whether the company stayed engaged after the system was turned on. |
| Project management | How well was the project run? | Timelines, coordination of permits and inspections, handling of delays, and whether the customer was kept informed throughout. |
A company can carry a 4.8-star average and still show a consistent pattern of savings that never materialized, or calls that went unanswered after activation. We see that.
Company Character
Reviews, even properly weighted, don't tell the full story. Company character captures patterns that exist outside any individual review.
Cross-platform consistency. A company with a 4.9 on Google and a 2.8 on Yelp is telling you something neither number says alone. When ratings disagree across platforms, it is one of the strongest predictors of how customers feel years later. Satisfied customers tend to be satisfied everywhere. Disagreement means something is being hidden, incentivized, or ignored.
Deception patterns. One in four negative solar reviews contain allegations of deception. But we draw a careful line. Timeline delays are frustrating. Permit backlogs are out of the installer's control. We do not treat operational problems as fraud. What we look for: unauthorized charges, forged documents, and explicit promises broken on material terms. Incompetence is not deception. Poor communication is not fraud. That distinction matters, because a company that crosses into deception is a fundamentally different risk than one that executes badly.
The ownership experience. We measure the satisfaction rate among customers who have lived with their system for over a year. Not what the company promises. What actually happens after the first twelve months.
BBB standing. Accreditation status, complaint history, and how the company responds when things go wrong.
Review patterns. Signs of coordinated, incentivized, or manufactured reviews. Clusters in narrow time windows. Duplicate text across companies. Patterns that don't match organic behavior.
Company character can only lower a score, never raise it. A clean BBB record does not offset a pattern of deception. Penalties compound. This is deliberate. Gaming the Trust Score requires fooling multiple independent systems at once, and the signals that carry the most weight are the ones hardest to fake. You cannot manufacture satisfied customers years after installation. You cannot coordinate your ratings across platforms you don't control. The only reliable way to score well is to do good work and stand behind it.
Where we look
No single platform tells the whole story.
Google Reviews. Largest local business review platform. Broadest coverage of solar companies nationwide.
Yelp. Oldest local business review platform. Where detailed negative experiences surface that don't appear elsewhere.
Better Business Bureau. Complaint and accreditation platform. Formal disputes and how companies respond.
SolarReviews. Largest solar-specific review site. Reviewers are actively researching solar, and reviews include more technical detail about the installation.
EnergySage. Solar marketplace for comparing quotes. Reviews from homeowners who went through a structured shopping process before hiring.
Many large installers have dozens of separate listings on the same platform across different regions. There is no single "Google page" for these companies. There might be fifteen or thirty, each with different ratings. A consumer looking at one listing sees a slice. We see the full picture across every listing, every platform, every market.
Some companies have thousands of reviews. Some have fewer than twenty. The methodology accounts for both. A company with thin data carries more uncertainty, and the score reflects that.
What the Trust Score is not
A guarantee. A high Trust Score means a strong track record across every dimension we measure. It does not mean every project will go perfectly.
A paid placement. No company can buy a higher score. No lead generation company influences our methodology.
A price comparison. The Trust Score measures reputation and reliability, not cost. A high-scoring company may not offer the lowest price. But the lowest price doesn't tell you whether the savings will hold up or whether the company will be there when something goes wrong.
A few honest limitations. We cannot catch every coordinated review, but the reviews that carry the most weight, specific accounts from real customers about real experiences, are the hardest to fabricate. Companies with very few reviews carry more uncertainty, and the score reflects that. And scores change: as new reviews come in and companies evolve, Trust Scores update. A company that is improving will see it. A company that is declining will too.
Using the Trust Score
Whether you're starting your search and looking for the best installers in your area, or comparing three quotes and trying to decide which company to go with. Whether a neighbor just recommended their installer and you want to know if they're any good, or a friend asked you who they should call and you want to give advice you feel confident about.
The Trust Score exists for all of these moments. The research, the quotes, the comparisons, those are the easy parts of going solar. Knowing which company will still be there for you in year five is the hard part.
We did the work so you can decide with confidence. Find your solar installer on WattBot →