Voluntary Carbon

A voluntary carbon credit represents one tonne of CO2 equivalent avoided or removed, bought not for legal compliance but voluntarily, to offset emissions or back a net-zero claim. This is the opposite of a capped allowance like the EU ETS: there is no government issuing a fixed number of permits, only projects that claim to have reduced emissions and registries that certify them. The dominant standards are Verra and Gold Standard, and credits split between avoidance (protecting forests, renewable energy, cookstoves) and removals (afforestation, biochar, direct air capture).

The defining feature is price dispersion driven by quality. A low-quality avoidance credit can trade for one to five dollars a tonne, a nature-based removal for tens of dollars, biochar for over a hundred, and engineered direct air capture for hundreds to over a thousand. The market's credibility took a severe blow in 2023 when investigations found the great majority of certain rainforest credits were worthless, and transaction volumes fell more than half from 2022. Headline market value is on the order of 1.7 billion dollars, though estimates vary widely by how credits are counted.

Credits trade over the counter and through brokers, with spot platforms (Xpansiv CBL) and some futures, and are tracked in the registries that issue them. The major new source of demand is CORSIA, the UN aviation offsetting scheme, which bolts a compliance-style buyer onto this voluntary supply. The buyer base splits along the same quality line as the credits. Airlines built "carbon-neutral flight" marketing on the cheapest avoidance credits, and several have since been forced to drop or defend those claims, including a 2024 Dutch court ruling that KLM's green advertising was misleading. At the other end, buyers chasing credibility rather than a bargain, Bill Gates and the Frontier advance-purchase coalition backed by Stripe, Alphabet, and others, pay hundreds to over a thousand dollars a tonne for engineered direct air capture, deliberately avoiding the cheap forest credits entirely. The whole market lives or dies on one question, whether a credited tonne was ever really avoided, which is why verification and integrity matter more here than price.