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Carbon credits, in plain language.
No prior knowledge assumed. What a credit is, how one is created and checked, who buys it, and where our programmes fit.
One credit equals one tonne.
A carbon credit is a certificate saying that one tonne of greenhouse gas, measured as carbon dioxide equivalent, was either kept out of the atmosphere or taken back out of it. It exists because someone did something measurable and had it independently checked.
Greenhouse gases are pooled globally: a tonne avoided in Alberta has the same effect on the climate as a tonne avoided anywhere else. That is why a tonne can be measured in one place, verified there, and bought by someone elsewhere.
Credits are not permission to pollute and they are not a substitute for cutting your own emissions. They pay for work that would not otherwise be financed.
How a credit is actually made.
Six steps, in order. Nothing can be sold until step five, and step five depends on an outside party.
A rulebook is chosen
Every credit follows a published method — a document that sets out exactly what counts, how the tonnes are calculated, and what evidence must be kept. Nobody invents their own maths.
The project is described and checked before it starts
The plan is written up and reviewed by an independent auditor, called a validation and verification body. This step is validation: does the plan match the rulebook?
The activity happens and is measured
The operator does the work — making biochar, sealing a well, recovering logs — and records the data the rulebook asks for. Doing this digitally is known as dMRV: digital measurement, reporting and verification.
An auditor verifies the results
The same kind of independent auditor checks the data after the fact, usually once a year. This step is verification: did the claimed tonnes really happen?
The registry issues the credits
A registry is a public database that mints one credit per verified tonne, each with a serial number. Registries are independent of the people running the project.
A buyer purchases and retires them
When a buyer uses a credit against their own footprint, it is retired — permanently cancelled in the registry so it can never be sold or counted again.
What separates a good credit from a bad one.
The criticism aimed at carbon markets is usually aimed at credits that fail one of these tests. Independent bodies now publish the tests openly.
Additional
The reduction or removal would not have happened anyway. If the activity was already profitable or already required by law, it does not earn credits.
Measured, not guessed
The tonnes rest on instrument readings, weighbridge tickets and records that an auditor can retrace — not on a model output alone.
Durable
Carbon put into a stable form, like biochar, is expected to stay put for centuries. Avoided emissions, like a methane leak stopped for good, never enter the air at all.
Counted once
Serial numbers and public registries stop the same tonne being sold twice or claimed by two countries at the same time.
Conservative
Where there is uncertainty, the method is required to round against the project, not in its favour.
Independently governed
The registry and the auditors are separate from the developer. The developer never decides what gets issued.
LEARN MORE
- ICVCM, Core Carbon Principles
- VCMI, Claims Code of Practice
- IPCC, Sixth Assessment Report, Working Group III
The Integrity Council for the Voluntary Carbon Market publishes the Core Carbon Principles for supply-side quality; VCMI publishes rules for how buyers may describe their use of credits.
Two markets, two kinds of buyer.
Compliance markets
Governments cap or price emissions and regulated companies must settle up each year. Around 80 carbon taxes and emissions trading systems are in operation worldwide, covering roughly 28% of global emissions and raising over US$100 billion in 2024.
Voluntary markets
Companies buy credits by choice, to address emissions they cannot yet eliminate or to support climate work in their supply chain. Reported voluntary transaction value was about US$535 million in 2024.
The words you will meet.
Every term used anywhere on this site, defined once.
- Tonne of CO₂e
- The unit everything is measured in. 'e' means equivalent: other greenhouse gases are converted into the amount of CO₂ that would trap the same heat.
- Carbon credit
- A tradable certificate representing one tonne of CO₂e either kept out of the atmosphere or removed from it, verified against a published method.
- Reduction vs removal
- A reduction stops an emission that would otherwise occur, such as a leaking well. A removal takes carbon out of the air and stores it, such as biochar in soil.
- Methodology
- The published rulebook for a project type: what qualifies, how tonnes are quantified, what evidence is required.
- Baseline
- What would have happened without the project. Credits are the difference between the baseline and the measured reality.
- Additionality
- Proof that the activity depended on carbon finance and is not simply business as usual or a legal obligation.
- Registry
- The independent public database that issues, holds, transfers and retires credits. Puro.earth and the International Carbon Registry are two examples.
- VVB
- Validation and verification body — the accredited, independent auditor that checks the plan before and the results afterwards.
- dMRV
- Digital measurement, reporting and verification: collecting project data through software and instruments instead of spreadsheets and site visits alone.
- Issuance
- The moment the registry creates the credits, after verification. Before issuance, volumes are only estimates.
- Retirement
- Permanent cancellation of a credit in the registry once it has been used for a claim. A retired credit cannot be resold.
- CORC
- CO₂ Removal Certificate — the name Puro.earth gives to its credits. CORC200+ indicates storage expected to last over 200 years.
- Compliance market
- A market created by law, where regulated emitters must surrender allowances or credits. Canada's industrial carbon pricing systems are an example.
- Voluntary market
- Buyers, usually companies, purchasing credits by choice rather than legal requirement.
- Grouped project
- One registered programme that many separate operators join, sharing one method, one audit cycle and one registry account.
- SPV
- Special purpose vehicle: a separate company set up to hold one programme's contracts, registry account and credits.
Where TCC fits.
We pay for and run the process above on behalf of operators who are already doing the physical work.