Carbon credits vs Proof of Growth: what each one proves
Carbon credits and Proof of Growth both try to put a number on climate action, but they answer different questions. A carbon credit claims that one tonne of CO2 was kept out of the air or taken out of it. A Proof of Growth record shows that one specific tree exists, where it grows, and that it is still alive. Knowing the difference protects you from the green claims that do not hold up.
What a carbon credit is
A carbon credit represents one tonne of CO2, or the same effect from other greenhouse gases, either avoided or removed. A project follows a published method to estimate its effect, an auditor reviews the estimate, and a registry issues credits that a company can buy and retire against its own emissions.
Some credits come from removing carbon, for example by growing forests. Many come from avoiding emissions, for example by protecting a forest that was supposedly about to be cut down. Avoided emissions depend on a guess about what would have happened otherwise, and that guess is where the trouble starts.
Where forest credits went wrong
- Over-counting. In 2023 an investigation by The Guardian, Die Zeit and SourceMaterial concluded that most rainforest credits from the largest certifier were unlikely to represent real reductions. The certifier disputed the findings.
- A pattern, not one case. A 2026 review in Nature Communications brought together six independent evaluations of 44 forest protection projects. Together the projects claimed more than ten times the avoided deforestation that independent estimates supported.
- Permanence. A credit sold today assumes the forest is still there for decades. Fire, logging and drought do not read contracts.
- Additionality. A credit is only worth something if the action would not have happened anyway, and that is hard to prove after the fact.
The rules are tightening
Regulators have noticed. In the European Union, Directive (EU) 2024/825 has applied since 27 September 2026. It bans claims that a product sold to consumers is climate neutral, or has a reduced or positive climate impact, when the claim rests on offsetting emissions.
That moves the value from certificates to evidence: records that show a specific action, in a specific place, that anyone can check.
What Proof of Growth proves, and what it does not
Proof of Growth is the on-chain record written for every planted and verified tree. It holds the tree's location, the date it was planted and a location-tagged photo, and it is confirmed again every year the tree lives.
It does not claim a tonne of CO2. It shows that a real tree exists and is alive, one tree at a time. An estimate of the carbon that tree captures can be built on top of the record, but the record itself is the evidence, not the estimate.
In short, a carbon credit is a claim about tonnes that someone has calculated. Proof of Growth is evidence about trees that anyone can check. It is not a certified carbon credit.
Side by side
- What it measures. A carbon credit measures tonnes of CO2, estimated. Proof of Growth records one specific tree, observed.
- Who checks it. A carbon credit is checked by an auditor, usually once per reporting period. Proof of Growth can be checked by anyone, at any time, on a public blockchain.
- Over time. A carbon credit is issued once and then retired. Proof of Growth is confirmed again every year the tree lives.
- If the trees are lost. A carbon credit may already have been sold and used. Proof of Growth stops: no confirmation, no further reward.
- What it is for. A carbon credit is bought to offset emissions. Proof of Growth rewards planting trees and keeping them alive, and gives companies a trail they can show.
Can they work together?
Yes, and that is the most useful way to see them. A credible removal credit needs exactly what Proof of Growth records: which trees, where, planted when, and whether they are still alive. Evidence for each tree does not replace certification. It makes certification easier to trust.
Common questions
Are carbon credits a scam?
Not as a whole, but the market has a serious quality problem. Independent studies have found that many forest protection credits were over-counted, sometimes by a wide margin. Removal credits that can be checked and are monitored for years are far more reliable than credits based on estimates of what might have happened.
Is Proof of Growth a carbon credit?
No. Proof of Growth is an on-chain record that a specific tree was planted, where it grows, and that it is still alive in later years. It is evidence about trees, not a certified claim about tonnes of CO2.
What changed for green claims in the EU in 2026?
Since 27 September 2026, EU consumer law bans claims that a product is climate neutral, or has a reduced or positive climate impact, when the claim is based on offsetting. Claims now need to rest on what a company actually does.