Greentons

Greentons are a unit used in climate accounting to quantify the net environmental benefit of greenhouse gas mitigation projects. Conceptually similar to carbon credits, one Greenton represents one metric ton of CO2 equivalent avoided or sequestered, adjusted for factors such as additionality, permanence, and leakage to ensure comparability across projects.

Calculation and verification: Projects estimate emissions reductions using standard methodologies and are verified by independent registries. The resulting quantity is recorded as Greentons, which may be traded or retired in voluntary markets. It is common to apply a permanence consideration and to account for gas-specific global warming potentials when aggregating reductions.

History and status: The term Greenton appeared in climate accounting literature in the early 2010s and was popularized by international standards bodies that promote standardized environmental credits. In practice, Greentons have been used primarily within voluntary markets and pilot programs, with limited uptake in some regulatory regimes.

Adoption and use: Some multinational corporations, cities, and non-governmental organizations have piloted Greenton-based accounting within sustainability reporting and project finance. However, mainstream regulatory frameworks have not universally codified Greentons as an official currency for compliance markets.

Criticism and considerations: Critics argue that Greenton markets can overstate benefits if permanence is uncertain or if leakage is not fully accounted for, leading to potential double-counting. Proponents contend that Greentons offer a transparent, standardized way to compare mitigation outcomes and to direct capital toward verifiable climate benefits. See also: carbon credit, carbon offset, CO2e.