A wonky accounting device is becoming an essential part of climate strategies

This may have been the year when a somewhat wonky component of sustainability strategy — the environmental attribute certificate (EAC) — went mainstream. The past 12 months have seen certificates for low-emission products minted in multiple sectors, including cement, iron and carbon capture. In parallel, standard setters are close to giving companies greater leeway to use certificates in carbon accounting and target setting. 

“It definitely feels like this year something really clicked across the board — with buyers and suppliers, but also the standard setters seem to be getting it, the environmental NGOs, even governments,” said Kim Carnahan, CEO of the nonprofit Center for Green Market Activation (GMA).

The approach is designed to unlock investment in climate solutions by separating the environmental benefit of a product from the product itself. Take sustainable aviation fuel, an area where EACs are well established. There are companies that are willing to pay a premium to have employees travel on flights that burn fuel derived from used cooking oil and other sustainable sources, but it’s impractical for an airline to respond to that demand by changing the fuel mix on specific flights. 

EACs solve the impasse by allowing airlines to deploy sustainable fuel wherever available and to sell certificates for the associated emissions savings. Companies that purchase the certificates deduct the savings from their greenhouse gas inventories, and retire the certificates so that they cannot be used again. The Sustainable Aviation Buyers Alliance, a project co-managed by GMA, Environmental Defense Fund and RMI that counts Amazon and Visa as members, has used the approach to aggregate $550 million in demand for sustainable aviation fuel certificates since 2021.

Tech giants lead the way 

The approach is now proliferating, with the tech giants — which are trying to balance ambitious emissions goals with data center build out — leading the way. “A major driver behind EACs today is thinking about how we decarbonize data centers,” said Katherine Vaz Gomes, a decarbonization engineer at Carbon Direct, a consultancy. “There was a demand beforehand, but the hyperscalers have really accelerated the need to bring this to market.”

This May, for instance, Microsoft used guidelines Gomes helped write when it purchased EACs covering more than 620,000 tons of emission reductions from Sublime, a startup that has developed low-carbon cement. Microsoft will use Sublime’s product in its construction projects when possible, but most cement is used within a few hundred miles of where it is produced, and Sublime is still building its first commercial facility. Purchasing the certificates allows Microsoft to support the startup — and claim the associated emissions savings — even when it cannot use Sublime’s product.

Other data center projects will also involve EACs. In October, Meta said it would use ones purchased from Electra, a startup that is building a facility to produce low-carbon iron, to cover emissions associated with its infrastructure projects. The same month, Google announced plans to use EACs in a deal to fund technology to capture 90 percent of emissions from a new natural gas plant in Illinois. The electricity from the plant will be added to the grid that serves Google data centers in Illinois and Arkansas.

Renewable energy certificates (RECs), another established form of EAC, have long been used to help pay for clean energy projects. But a new EAC was required in this case: Unlike solar and wind, which produce zero emissions after construction, the certificate needed to account for the fact that not all the emissions will be captured, said Iain Kaplan, a partner at NorthBridge Group, the consultancy that developed the methodology for the certificate.

Broader coalitions

Carnahan and colleagues are working to ensure these individual projects are followed by broader industry-wide efforts. In September, GMA teamed up with fellow nonprofit RMI to launch the Sustainable Concrete Buyers Alliance; founding members include Amazon, Prologis and Meta. The following month, Nevoya, an electric freight company, was announced as the winner of a request for proposals designed to kickstart work on EACs for road transport. The center is also consulting on plans to create a buyers alliance for low-carbon chemicals.

This momentum will likely be accelerated if, as looks likely, two influential standard setters incorporate use of EACs into their guidelines. The Science Based Targets initiative is revising its net-zero framework and the latest draft allows companies to use EACs to hit targets — albeit only for specific types of Scope 3 emissions, a restriction that Carnahan would like to see loosened. Over at the Greenhouse Gas Protocol, a nonprofit that creates carbon accounting guidelines, a working group focused on market instruments is due to publish a white paper later this month that is expected to recommend integrating EACs into future rules.

In addition to the flurry of new activity, 2025 also saw a subtler shift around EACs. The term is broadly used and encompasses two market instruments that are often criticized: RECs, which are faulted for doing little to add new renewables to the grid, and voluntary carbon credits, which, in the worst cases, have been issued to projects with no climate benefit. Other EAC projects have on occasion suffered from guilt by association, but the most recent crop has largely been evaluated on their own merits.

This and other factors point to an increasingly important role for EACs in climate strategies. “We’ll see broader adoption beyond tech and data centers, with chemicals, steel and cement increasingly using EACs to support decarbonization,” said Greg Matlock at EY Americas, who tracks use of EACs in heavy industry. “In many instances, EACs will move from being an add-on to being a core part of how projects are structured.”