What is Additionality in Energy Attribute Certificates (EACs)?

Additionality, a term with roots in mid-20th-century policy discourse (before being popularised in carbon markets), is the test of whether an action or behaviour, such as a purchase or trade, creates a measurable positive outcome beyond what would have happened anyway if that action did not take place. Note: We are not here to discuss carbon instruments, rather, Energy Attribute Certificates (EACs) , but if it is beneficial, see our article exploring the difference between the two. Now, let’s unpack additionality further specifically within the context of EACs.

In formal GHG accounting, additionality is a project-level concept (meaning, assessed by comparing intervention outcomes against the likely outcomes of the project/intervention not having occurred at all). Contrastingly, in EAC markets, the term is often used more loosely as shorthand for purchaser impact, and can thus describe purchases that are deemed more impactful than others. ‘Impact’ typically describes EAC spend that has been directed towards helping newer or higher-quality generation get deployed. This can happen in a number of ways, and results in EACs with certain attributes being seen as more desirable, which in turn creates more premium, differentiated markets with stronger price incentives for generation . This mechanism directly rewards renewable energy producers for the energy they have generated and how they generated it.

Don’t EACs prove “additionality” by default?

Not quite. In the Energy Attribute Certificate (EAC) market, a GO , REC , or I-REC is not automatically a marker of “additionality”. In their most basic sense, EACs are tradable instruments representing the renewable attribute of a unit of electricity. They are used for market-based Scope 2 reporting, and under SBTi, the EAC can be used to support the Low-Carbon Electricity (LCE) alignment pathway via systems-contribution claims. Depending on the circumstances of their origin and procurement, they can contribute towards provably additional outcomes, but this is not established by default.

A corporate end-claimant, who has purchased EACs, can lay claim to the attributes an EAC represents and make legal renewable energy claims as a result. Here, procuring EACs for renewable claims is better than not procuring them, and the buyer has supported a renewable energy producer financially. This does not automatically mean any measurable outcomes have occurred as a result of their purchase. Adherence to voluntary best practices and specific procurement methods plays a huge role in determining this.

So, voluntary best practices are where additionality lies?

Typically, but not always, and this presents a common misunderstanding. Compliance and voluntary regimes are each capable of requiring EAC purchases to have provable impact and additionality. However, when buyers are entering the market for the first time, and of their own accord (rather than government mandate), it’s unsurprising that they will voluntarily seek out the EAC procurement method with the highest level of provable additionality, given that nobody is forcing them to procure in the first place. As a result, voluntary schemes typically drive innovation regarding ‘impact’ in the EAC market, even though measurable outcomes that count as “additionality” are not tied exclusively to either the compliance or voluntary domain. The specific impacts of any EAC procurement initiative should be assessed independently of the motive that prompted the EAC purchase.

Which specific EAC purchase types and attributes are considered indicators of “additionality”?

Just for context; let’s remember what EACs are even for. They’re for claiming your share of verified renewable energy production (finite) when you are drawing energy from the grid. So; the key parameter here, from a perspective of maximising additional environmental impact, is the fact that you are personally drawing from the grid, using a book and claim system . That limits the actions that you can take, otherwise, in the most extreme sense, maximum additionality would mean commissioning your own renewable energy generation facility. This project would only exist because you created the demand, took initiative, assumed all of the development risk, and supplied the capital needed for it to be built. But for EAC purchases, which are designed to facilitate renewable claims using grid-purchased electricity, conscientious purchases usually seek out desirable attributes, supporting production as best a buyer feasibly can.

More desirable energy attributes include:

• Commissioning Date Attributes: Procuring EACs sourced from newer devices (e.g., SBTi's generator-age requirements )
• Unsupported Devices: Procuring EACs from devices that have not received government support.

Not only this, but some independent schemes verify that EACs fulfil additional third-party biodiversity and environmental criteria.

• Independent Criteria Schemes: Prioritising EACs with additional quality labels

Finally, temporal and geographic matching are widely considered best practices. RE100 already mandates that credible claims adhere to geographic market-boundary requirements, while SBTi’s CNZS V2.0 includes hourly reporting (not matching) as mandatory for the largest firms. GHG Protocol is considering mandatory hourly matching through its ongoing Scope 2 revision .

• Geographic Attributes : Procuring locally sourced EACs
• Temporal Attributes : Procuring EACs on an hourly basis

And whilst these attributes, schemes, and matching best practices are not always provably causal with regard to new rollout, they’re each associated with creating stronger price incentives for generation and are thus considered higher impact, with additionality used as shorthand here for purchaser impact. For the strongest evidence of causality, long-term contracts, within which any of the aforementioned purchase types and attributes can be included, are considered the clearest route, especially when associated with brand-new projects and a producer who can verify the commercial importance of your contribution.

Why are long-term contracts relevant to EAC additionality?

In addition to any impact associated with specified generation attributes, long-term EAC offtake agreements and PPAs can provide strong evidence of procurement impact. This is because, for producers, they represent predictable, multi-year revenue, which can reduce project risk, a constraining factor in the rollout of new renewable capacity. However, this revenue certainty constitutes evidence of additionality only where the contract materially influenced the project’s financing. If the project would have simply gone ahead otherwise, there’s no evidence of additionality.

What measurable outcomes exist for EAC additionality?

Additionality should always be explained and its outcomes evaluated in real-world terms. This typically means improved project viability from a financial standpoint, but can also manifest as additional benefits such as biodiversity protection, where a production facility is assessed against enhanced biodiversity criteria and a set portion of procurement proceeds is used for conservation purposes ( EKOenergy is widely regarded as the strongest, most widely recognised example of this in Europe, with Green-e widely regarded as a (non-affiliated) “equivalent” in North America).

How to make informed EAC procurement decisions, with additionality in mind?

So, additionality calls. Whether you are compelled to do so by a scheme such as LEED (which mandates particular quality labels and contract lengths when using EACs), or simply want your renewable energy purchases to make a provable difference, you have a few options. For corporate buyers, additionality is not something a single purchase or slogan can capture entirely; it is best treated as an ongoing procurement discipline. This is especially true for firms that want high-integrity claims and a defensible narrative for each consumption period, without adding another layer of administrative overhead. To help with this, Soldera offers a combination of the following based on your individual needs and preferences:

1. Access to long-dated contracts.
2. Access to more desirable energy attributes.
3. Enabling EAC additionality via hourly claims: Soldera helps sustainability and energy teams move from basic annual matching towards hourly matching , supporting the market infrastructure, EAC metadata, and cancellation evidence needed to support your 24/7 carbon-free energy goals.
4. Additional environmental impact by project credentials: For companies that also want to prioritise projects with stronger environmental and social contribution, EKOenergy-labelled certificates add a recognised ecolabel layer on top of standard EAC procurement, allowing you to support high-impact, biodiversity-conscious renewable energy production.

Book a demo to discuss how Soldera can turn additionality from a procurement ideal into a practical EAC workflow for your team.