A Standardized Test for Carbon Removal

In the wake of a wave of scandals in the carbon credit market, a boatload of brokers arrived to mediate between buyers and sellers and improve the integrity of carbon claims. In came the consulting firms staffed by scientists to advise companies on which credits to buy, ratings agencies to assess individual carbon projects, and carbon credit registries with new business models that promised to be more scrupulous than those that came before.

But to Peter Minor, none of these players is getting at the root issue. So Minor, an alum of the carbon removal advocacy group Carbon180, is launching his own company, Absolute Climate, to solve what he sees as the two biggest problems in the carbon credit market: inconsistent accounting and conflicts of interest.

“If we don’t fix these things, the carbon removal industry may never get to the trust and adoption that it’s going to need to get to enough scale to actually reduce harms,” Minor told me.

Absolute Climate’s solution is a new standard, or set of rules, for accounting for the climate benefits of carbon removal projects that would ensure carbon credits from different projects are comparable on an apples to apples basis. That is, as long as it’s widely accepted by a market that’s fraught with divisions.

To date, the registries — the businesses that certify and sell carbon credits — have been the ones to create and oversee accounting standards. But the registries have an incentive to set permissive requirements, Minor said, because the more credits they certify, the more they can sell. This arrangement has resulted in standards that all use slightly different criteria to account for how much carbon has been removed. These differences show up not just across registries, but also within registries across different types of projects.

Here’s an illustrative example: Climeworks is a company that builds industrial-scale plants to suck carbon out of the air, compress it, and inject it underground. Under the carbon removal registry Puro’s standard, Climeworks must take into account the emissions related to clearing the land, building the plant, powering it, transporting the captured carbon, and injecting it before coming up with the net total tons of carbon the plant has removed and the number of credits the company can sell.

Compare that to Red Trail Energy, which owned a corn ethanol refinery and recently began capturing carbon emitted from the facility’s fermentation tank and injecting it underground. Corn absorbs carbon from the atmosphere as it grows, and Red Trail puts away some of that carbon permanently. But to calculate how many carbon removal credits Red Trail can sell based on this project, Puro does not require the company to account for the emissions associated with growing the corn, transporting it to the plant, or heating it up using a natural gas boiler. Nor does it require measurement of the emissions released when the ethanol is burned in a vehicle. If it did, all those emissions would exceed the amount of carbon Red Trail is storing.

On the Puro registry, Climeworks’ credits and Red Trail’s credits are identical, both advertised as carbon removal. But to Minor, the credits are fundamentally different — one is a truly net-negative process, the other reduces emissions to the atmosphere from an existing source. Once the world has cut carbon nearly to zero, only the first project could provide a counterweight to any residual emissions and help halt or even reverse warming. Minor worries that if both are called carbon removal, the difference won’t be clear until it’s too late.

“We might get to the point where we’ve scaled up the infrastructure and the political economies around certain projects because they were cheaper or more efficient in our minds, but actually it’s just that they weren’t net-negative,” he said. “So we may put ourselves in a position where we can’t actually meet our climate goals.”

Minor is not alone in this concern. Several recent peer-reviewed papers have identified this as a pervasive issue and proposed ideas for how to solve it. “Big picture, we want net flux of carbon out of the atmosphere into storage,” Anu Khan, founder of the non-profit Carbon Removal Standards Initiative, told me. “We want to set rules that motivate this and allow us to add it up over time.”

Absolute Climate’s solution is based on a framework developed by scientists from Lawrence Berkeley National Laboratory. Minor described it as a single standard that verifiers can apply in exactly the same way to every method of carbon removal and determine whether a given project is net-negative or not. Each type of carbon removal, like enhanced rock weathering or direct air capture, will still require individualized rules for how it should conduct physical measurements, he said. But the project scope — the question of what to measure — will be consistent.

In practice this doesn’t seem like a major paradigm shift. It requires project developers to identify all the activities associated with their project that either release or store carbon, measure each one, and add them together to get the net result. The main difference is that they can’t selectively ignore certain emissions in the calculation if, for example, those emissions are related to a co-product like ethanol.

To meet Absolute’s standard, a project must also be able to store carbon for 1,000 years, similar to the amount of time carbon emissions stay in the atmosphere. That’s in contrast to most standards, which have different requirements depending on the project type. For example, reforestation and soil carbon storage projects typically only have to store carbon for 100 years, while any project injecting carbon underground has to promise 1,000 years.

Any carbon credit registry can adopt the standard, and the company will earn a fee for each project certified under it, rather than for the number of credits certified. One registry, called Evident, which sells renewable energy credits, has already agreed to use it.

But it’s hard to imagine other registries that have invested significant time into developing standards — and certified credits using them — throwing those out anytime soon. When I wrote about the questions raised by the Red Trail Energy project earlier this year, Puro defended its rules. Marianne Tikkanen, Puro’s co-founder and head of standards, said the point of carbon credits is to pay for an intervention that wouldn’t have happened otherwise. In this case, that meant it was appropriate to isolate the carbon capture and storage part of the project when it came to certifying credits, she said.

Adding yet another layer between buyers and sellers could also increase costs. “There are market pressures that drive towards vertical integration of registries that do everything,” Khan told me. “Cost savings are a really big deal. Companies want to buy credits at the lowest cost that is good enough for the type of claim that they want to make.”

Absolute will face competition, both in the literal market and in the marketplace of ideas, from Isometric, a registry my colleague Katie Brigham wrote about earlier this year. Isometric has tried to address the conflict of interest problem by charging fees to buyers — not sellers — for verifying carbon credits.

In setting such a high bar, Absolute also risks having a chilling effect on the carbon removal industry by blocking promising projects that are working through yet-unproven science or have other early-stage growing pains from a key source of funding. As a solution, Absolute plans to designate some projects as part of an “innovative class.” One example Minor gave me is a new direct air capture company that can’t procure enough renewable energy to power its pilot plant and has to run using dirty power. “We can allow them to take those shortcuts where it makes sense, assuming their buyers or the governments that they’re delivering to are okay with that, but we’re going to be transparent about it,” he said.

In short, there will be two classes of credits under the Absolute standard — those that really, definitely, represent carbon removed from the atmosphere, and those that may or may not but support projects that maybe one day could.

This is all a lot to make sense of, and it’s possible Absolute could introduce more confusion into the market with all these new terms and definitions.

“This is most valuable, I think, for those people who care about whether or not what they are investing in can play that future role of being actual carbon removal,” Corinne Scown, a scientist at Lawrence Berkeley National Laboratory whose work influenced the Absolute standard, told me. But for those who just want to fund projects that help fight climate change, the distinction matters less, she said. “Mitigation is still really valuable. We do want people to have a way to pay for that.”

While there are some companies trying to do the former, most are aiming mainly to reduce the amount of emissions on their annual sustainability reports. Today, these reports are voluntary and companies can use whatever math suits them. But soon they will be required by governments such as the European Union and the state of California, which will have rules about how companies should calculate their carbon footprints. Depending on how those rules are implemented, the distinction between an Absolute-certified carbon credit and a Puro-certified carbon credit could matter a great deal.