A travel product with a community-solar impact claim attached is asking you to accept someone else's number. Whoever produced it had an interest in it being large. The claim may still be perfectly sound, and finding out takes about six questions, none of which need a technical background.
This is the assessment order, with the rules that govern each answer and what a weak answer looks like.
Ask what stage the capacity is at
Solar capacity gets reported at two very different stages, and the gap between them is where most inflated claims live. Capacity that is built, connected and generating produces electricity today. Capacity that is contracted, permitted or in development produces none until it is commissioned, which may be years out.
A provider quoting one combined figure is telling you very little. Ask for the split, and ask that every current emissions claim be derived from operating capacity alone. A large pipeline is a reasonable thing to have and a reasonable thing to talk about. It becomes a problem when it is folded into a number described in the present tense.
The Federal Trade Commission has a rule pointing directly at this. Under the Green Guides at 16 CFR 260.5, marketers should clearly and prominently disclose if a claimed reduction will not occur for two years or longer. The Commission's own worked example is a travel company: an agency inviting customers to neutralize flight emissions, where the proceeds fund projects that will not reduce emissions for two years, is making a deceptive claim unless it says so.
Ask for the capacity factor, not just the megawatts
Installed capacity is a rating rather than an output. A one megawatt array does not produce one megawatt-hour every hour, because the sun is not always on it. The ratio between rated capacity and actual annual generation is the capacity factor, and it is the input where optimism most often enters.
Fixed-tilt solar generally reaches somewhere in the mid-teens to low twenties as a percentage, depending on latitude and siting. A claimed figure well above that range should prompt a question about whether the array tracks the sun, where it is, or whether anyone checked. You can sanity-check the answer against any published solar resource map for the region in a couple of minutes.
If a provider cannot tell you their capacity factor, they are quoting a number they did not derive.
Ask which grid the electricity displaces, and from which year
Generation avoids emissions in proportion to what it displaces, so converting megawatt-hours into tonnes needs an emission factor for the specific grid the project feeds. A project in a coal-heavy grid displaces considerably more carbon per unit than the same project on a cleaner one.
Two follow-ups separate a real methodology from a marketing number. Which published factor, from which authority? And from which year, given that these are revised regularly and a factor held at an old value makes the same array look better every year as the grid around it cleans up. India's Central Electricity Authority, for instance, publishes a Combined Margin annually: the 2023-24 figure is 0.757 tonnes per megawatt-hour and the 2024-25 figure is 0.736, so the choice of vintage moves the answer by roughly three percent on its own.
A falling factor is the correct result rather than a problem, and a provider who volunteers that their number will shrink is telling you their methodology is honest.
Ask who holds the certificates
This is the question that decides what you are allowed to say afterward, and it is the one most often skipped.
When a project generates renewable electricity, the environmental attributes can be sold separately as certificates. Under the Green Guides at 16 CFR 260.15, a marketer that generates renewable electricity but sells the certificates for all of it may not then represent that it uses renewable energy. The same logic governs what you can claim as the buyer.
So ask plainly: are certificates generated, who holds them, and are they retired or sold? If they are sold to someone else, the environmental claim went with them, and neither you nor the provider can make it. This has nothing to do with whether the project is good. It determines who owns the story.
Ask what the provider refuses to claim
A provider's disclaimers tell you more than their headline number. Funding new generating capacity and buying carbon offsets are different activities under different rules, and a provider who blurs them is either confused or hoping you are.
Look for explicit statements on three points. Whether they describe bookings as carbon neutral, which requires offsets rather than new capacity. Whether they claim the electricity as their own, which the certificate rule above governs. And whether cost savings quoted to the host site are modeled or invoiced, because projected savings presented as realized is a common and easily avoided overstatement.
We publish our own answers to all three, and the full arithmetic behind our figures, in how we calculate Dyme's renewable energy impact. Whatever provider you are assessing, that is the shape of the disclosure to ask for, and how to evaluate a travel provider’s climate-impact report covers the wider version of the same exercise.
Treat the comparisons as translations
Tonnes of carbon mean little to most readers, so impact claims arrive dressed in trees, football fields, homes powered or cars removed. These are unit conversions of a number you have already been given.
Two checks keep them honest. Divide back: an annual tonnage divided by a tree count should land near the standard absorption rate of roughly 20 to 25 kilograms per mature tree per year, and a figure far off that means someone picked a flattering conversion. And confirm the comparisons are not being added to each other, because the trees, the fields and the homes are all the same tonne described repeatedly.
The six-question checklist
- Capacity split. How much is built and generating, how much is pipeline, and is every current claim derived from the first number alone?
- Capacity factor. What is it, and is it within a plausible range for the technology and latitude?
- Grid emission factor. Which published source, which grid, and which year?
- Certificates. Are they generated, who holds them, and are they retired or sold?
- Timing. If reductions are more than two years out, is that disclosed clearly, as 16 CFR 260.5 requires?
- Equivalences. Do the comparisons divide back correctly, and is anyone adding them together?
A provider who answers all six without hesitation has done the work. One who needs to come back to you on four of them is quoting a number from a deck, and that is worth knowing before you attach your company's name to it.
FAQ: assessing solar impact claims
Is community solar a legitimate corporate impact claim?＋
It can be, and the legitimacy depends on specifics rather than on the category. Funding new generating capacity that would not otherwise exist is a real contribution. The claim weakens when pipeline capacity is reported as though it were generating, when certificates have been sold to someone else, or when reductions are years away and that is not disclosed. The six questions below separate one case from the other.
What is the difference between funding solar and buying carbon offsets?＋
They are different instruments under different rules. An offset is a claim on an emission reduction that happened somewhere else, governed by 16 CFR 260.5, which bans selling the same reduction twice and bans selling reductions the law already required. Funding new capacity causes generation to exist. A provider should be clear about which one they are doing, because only one of them supports a carbon-neutral claim.
Can we say our travel program runs on renewable energy?＋
Only if the certificates support it. Under 16 CFR 260.15, a marketer that generates renewable electricity but sells the renewable energy certificates for all of it cannot represent that it uses renewable energy. If your provider funds generation and the certificates go elsewhere, the honest description is what you funded rather than what you consumed.
What capacity factor should I expect from a solar project?＋
Fixed-tilt solar generally falls in the mid-teens to low twenties as a percentage, varying with latitude and siting. Tracking systems run higher. A claimed figure well above that range for fixed panels is worth questioning, and you can check it against a published solar resource map for the region in a few minutes.
Why does the grid emission factor year matter?＋
Because the factor falls as a grid adds renewable generation, so the same array avoids fewer tonnes on paper each year. Holding an old factor in place makes a project look progressively better without anything changing physically. Ask which year the factor comes from, and treat a provider who volunteers that their number will decline as a good sign rather than a bad one.
