How to reduce Scope 3 emissions using Energy Attribute Certificates

Scope 3 is one of the greatest challenges companies face on their path to net zero. Supply chain emissions, which can represent over 90% of an organisation’s total emissions, are often difficult to measure and even harder to influence. However, a significant share of this GHG output is linked to electricity consumption, making renewable electricity procurement a powerful lever for decarbonisation.

If used correctly, Energy Attribute Certificates (EACs) can be the primary tool to achieve significant GHG reductions. In this article, we explain how to calculate the share of your suppliers’ electricity usage that makes part of you Scope 3, how to allocate EAC purchases to your supply chain emissions, and how a digital portal can make a seemingly arduous process much easier.

How are supply chain — or Scope 3 — emissions divided?

Scope 3 emissions are divided into 15 categories, grouped into upstream and downstream activities. The first category, Scope 3.1, comprises all purchased goods and services, such as raw materials, components, services, and data hosting. This category is often one of the largest sources of emissions for companies, especially in sectors like retail, manufacturing, and services.

In many cases, a substantial part of that greenhouse gas output in Scope 3.1 is associated with electricity usage, meaning that these emissions can be reduced by encouraging suppliers to purchase renewable electricity.

How can suppliers procure renewable electricity?

According to the Greenhouse Gas Protocol’s market-based method, companies can claim the use of renewable electricity by buying Energy Attribute Certificates (EACs). Each EAC represents the environmental benefits of, typically, 1 MWh of clean electricity.

EACs are available worldwide and are the most accessible mechanism for purchasing clean energy. More than 90 countries have EAC systems in place, with more joining every year.

Companies can also procure renewable electricity by signing Power Purchase Agreements (PPAs) directly with renewable electricity producers. Keep in mind that, in most cases, PPAs must deliver EACs equivalent to the amount of physical power contracted to allow buyers to claim reduced emissions.

How much of my suppliers’ electricity consumption belongs to my Scope 3?

There are different methods to determine how much of a supplier’s electricity consumption corresponds to a brand owner — the company addressing its Scope 3 emissions.

We will focus on two methods: units-based and spend-based. Both methods rely on having, at a minimum, data on the supplier’s electricity consumption, for example, the total volume of electricity consumed by a given factory. A fraction of this energy usage is what must be allocated to a specific buyer.

The units-based method counts the total units produced by, for example, a factory, and assigns to the brand owner the percentage of electricity that corresponds to the percentage of units purchased. In other words, if your company purchases 60% of a factory’s production, then 60% of the factory’s electricity usage belongs to your Scope 3.

However, factories often produce multiple products, which complicates that calculation. Therefore, many brand owners opt for a spend-based approach, which calculates the percentage of the total revenue that a factory or production unit receives from them. The same percentage of electricity is then assigned to that brand owner’s Scope 3.

Both methods rely on different information being provided or calculated by suppliers, which requires collaboration and trust between parties. To build these relationships, companies like Logitech and Apple have started clean electricity buying programmes for suppliers, which smooth communication and provide essential guidance for suppliers on how to procure renewable electricity.

Setting renewable electricity targets for suppliers

The best, most actionable targets for renewable energy in the supply chain are set incrementally. They begin with achievable actions and are planned to scale up in a way that allows suppliers to become familiar with the process, establish communication flows, and work themselves upwards.

This approach has been used not only by companies but also by sustainability standards. In 2025, TCO Certified, the world-leading sustainability certification for IT products, introduced requirements for renewable energy in the final assembly of certified products. It mandated that at least 15% of the electricity used in each final assembly factory of certified products must be procured and/or generated from renewable sources.

A 15% renewable energy requirement might sound low, but it is important to make targets achievable and scalable. A year after releasing its renewable energy requirement, TCO Certified extended the mandate to a second tier of suppliers, including more companies in the certification’s scope.

How should EACs be allocated to count as part of my Scope 3?

When a company purchases EACs, it receives a cancellation statement, a document stating that the certificates have been retired from the market and redeemed in favour of the buyer. Cancellation statements specify the source, production facility, date, location, and volume — among other details — of the energy purchased. They also include a special text field known as the cancellation purpose, where suppliers must explain that the volume of electricity represented in that statement is allocated to the Scope 3 of a specific client.

If EACs are not cancelled in favour of a specific brand owner, that brand owner will not be able to claim the totality of those purchases as part of its Scope 3 and must use the percentage of the supplier’s total electricity consumption that is covered with EACs. In other words, if a supplier covers 40% of its total electricity consumption with EACs and does not allocate those purchases to any client, then all clients are allocated that 40% evenly.

Remember that, for suppliers, purchased electricity falls under Scope 2, which is in turn part of their clients’ Scope 3.

How Ecohz’ Renewable Energy Procurement Portal for Scope 3 helps

Ecohz’ Renewable Energy Procurement Portal for Scope 3 makes integrating renewable energy into your supply chain much easier. It allows companies addressing their Scope 3 emissions, named as brand owners in our portal, to receive essential information — such as the electricity consumption of their suppliers — set clear targets, and monitor the progress of their value chain partners.

At the same time, it makes it simple for suppliers to buy renewable electricity according to brand owners’ specifications anywhere in the world. They can also easily allocate purchases to specific clients through pre-defined cancellation purposes and buy additional volumes for their own consumption.

Through the Portal, brand owners can also set quality requirements for their suppliers’ renewable energy purchases. These include location or country, technology — for example, solar or wind — the age and size of the power plant, and other characteristics relevant to sustainability standards or initiatives like RE100. There is also a document repository where all proofs of consumption from suppliers — such as electricity bills — and cancellation statements are stored to be easily used for reporting.

In turn, suppliers can buy EACs in a fail-safe environment with a few clicks. Once they receive a request to purchase from one of their clients, they just have to request an offer for EACs with all the necessary characteristics. Within three days, they receive a quote for the volume needed.

In short, the Portal simplifies renewable electricity purchasing for Scope 3, putting you one step ahead in the journey to decarbonise your value chain.