What Is 'Additionality'? Why the UN's First Carbon Credits Are Under Fire

Two reports landed in the same week last month, both aimed at roughly 650,000 carbon credits — the first ever issued under the Paris Agreement's new UN carbon market. The credits came from a program handing out efficient cookstoves in Myanmar. The reports, led by the Global Forest Coalition and the Brussels-based watchdog Carbon Market Watch, say the project is tangled up with the country's military junta and may be overstating its climate benefit by a factor of seven.

Buried in that fight is a single technical word that decides whether almost any carbon credit on Earth is worth anything: additionality.

What does additionality mean in carbon credits?

A carbon credit is supposed to represent a ton of emissions that would not have been avoided without the money from selling that credit. That's additionality — the "but-for" test. But for the carbon revenue, would the solar farm, the forest preserve or the cookstove program still have gone ahead anyway? If the honest answer is yes, the project was going to happen regardless, and the credit doesn't represent any real reduction. It's just a receipt for something that was already going to occur.

Regulators reject credits that fail this test for an obvious reason: a company that buys a non-additional credit to claim "carbon neutral" status is doing pure arithmetic, not pollution reduction. Somewhere, on paper, one ton gets subtracted from the company's ledger while zero tons get subtracted from the atmosphere.

Why did regulators reject renewable energy carbon credits?

The clearest precedent came in August 2024, when the Integrity Council for the Voluntary Carbon Market — an independent watchdog that grades credit quality — rejected eight renewable energy methodologies covering roughly a third of all credits then on the voluntary market. The problem wasn't that wind and solar are bad for the climate. It's that those methodologies were written up to 20 years ago, back when renewables needed carbon-credit revenue to pencil out financially. Solar and wind costs have since collapsed and turned profitable on their own in much of the world, which means new projects built under those old rules often don't need the extra money anymore — they'd get built either way.

At the time, more than 280 million renewable energy credits sat in the voluntary market, enough on paper to offset roughly what Thailand emits in a year. Buyers included Audi, Shell and Total. Renewable credits were already trading at a discount — about $2 a ton, according to data provider MSCI, less than half the price of forest or methane-focused credits — because sophisticated buyers had already priced in the additionality doubt.

How is the Myanmar cookstove project different?

It's the newest test of the same question, on much higher-stakes ground. The Myanmar program started in 2018 under the old Clean Development Mechanism and, this February, became one of only two projects ever approved under Article 6.4, the Paris Agreement's replacement carbon market. Regulators required the project to apply more conservative assumptions before approval — a change that cut the credits issued by 40% compared with what the old methodology would have produced.

Carbon Market Watch says that adjustment still wasn't nearly enough. Its analysis, compared against peer-reviewed research, concludes the project is likely issuing seven times more credits than its actual climate impact justifies. The core dispute is something called "stacking" — many households keep using older, dirtier stoves alongside the efficient ones they were given, which erodes the real-world emissions savings. Carbon Market Watch says the science literature treats a 68% stacking rate as a conservative baseline; the UN told Climate Home News the project's own household surveys used stacking rates of just 8% and 10%.

There's a second, uglier layer here that has nothing to do with spreadsheets. For much of 2021 and 2022 — the period the credits actually cover — Myanmar's environment ministry was led by a colonel sanctioned by the European Union for backing the military regime that seized power in a 2021 coup. Auditors verifying the project couldn't leave the capital, Yangon, because of the conflict, and instead interviewed participants remotely over Zoom. "Due to ongoing armed conflict on the ground, the data currently used to justify carbon credit issuance in Sagaing by the Burmese military junta is unverifiable and highly likely fraudulent," Zaw Tuseng of the Myanmar Policy Institute, a contributor to one of the reports, told Climate Home News.

What do the people behind the project say?

The Climate Change Center, the South Korean NGO implementing the program, disputes the seven-times figure and says outside recalculations aren't "determinative of the level of crediting achieved." It told Climate Home News that remote verification was "an approved alternative under exceptional circumstances," not a shortcut, and that walking away from the program when the political situation changed "would not necessarily have been the most responsible outcome for the households involved." A spokesperson for the UN's climate body said its rules allow alternative verification when site access isn't possible, "while still maintaining conservative assumptions and environmental integrity safeguards."

Those credits aren't symbolic. They're headed mostly to South Korean companies, who can use them to meet obligations under the country's domestic emissions trading system — meaning a stacking-rate assumption made in a UN spreadsheet has a direct line to what a Korean manufacturer is legally allowed to emit this year.

Why does any of this matter if you never buy a carbon credit yourself?

Because the products and travel bought as "carbon neutral" lean on exactly this machinery. When a credit isn't additional, or when its stacking assumptions are off by a factor of seven, the neutrality claim printed on the box is a promise the underlying math can't back up. Carbon Market Watch's Isa Mulder put it plainly in response to the Myanmar findings: over-crediting "at any magnitude" is incompatible with a world trying to hold warming to 1.5 degrees Celsius. The dispute over one cookstove program in one country is really a dispute over whether that number can be trusted anywhere it's used.