AWS Adds Scope 3 Emissions Data to Customer Carbon Footprint Tool

Amazon Web Services has announced the second major update this year to its Customer Carbon Footprint Tool (CCFT), adding Scope 3 emissions data for the first time, calculated using an updated version 3 methodology.

To allow customers to make meaningful year-over-year comparisons and perform trend analysis, AWS has recalculated historical data back to January 2022 using the new method.

“I sit down with our customers on a weekly basis, and this has been our No. 1 customer-requested enhancement since I took over a couple of years ago,” Chris Walker, director for sustainability at AWS, told The New Stack.

Getting to this point has taken some time. Walker emphasized that the company’s approach has always been to prioritize data quality and transparency over speed to market: “We wanted to provide customers with high-quality, actionable data they can trust for their own sustainability reporting and decision-making, especially as expectations around emissions reporting become more stringent.”

An Updated CCFT Data Export

The CCFT data export has also been updated to include new columns breaking down emissions by Scope 1, 2 and 3 as defined in the Greenhouse Gas (GHG) Protocol, with emissions reported as metric tons of carbon dioxide equivalent (MTCO2e).

The simplified GHG definitions are:

• Scope 1: Direct emissions from AWS operations.
• Scope 2: Indirect emissions from purchased energy.
• Scope 3: All indirect emissions (not included in Scope 2) that occur in the value chain of AWS, including both upstream and downstream emissions (such as manufacturing of hardware, end-of-life emissions, etc.).

A lot of what is included in Scope 3 is embodied carbon, the carbon that is used in the manufacturing, transportation and eventual disposal of hardware, as opposed to “operational emissions” (i.e., emissions that are directly linked to data center operations such as those arising from the generation of electricity to power AWS services, or from fuel combustion in generators).

Digging into the details for AWS’ method, the Scope 3 emissions that are included are:

• Fuel- and energy-related activities (referred to as Scope 3 “FERA” as per the GHG Protocol).
• Embodied carbon of IT hardware (i.e., server racks).
• Embodied carbon of data center buildings.
• Embodied carbon of non-IT equipment (such as generators, air-handling units, etc.).
• Emissions from upstream transport and distribution (e.g., emissions arising from transporting server racks to the data center sites).

This likely covers the majority of Scope 3 emissions, but we should note that the current model excludes any embodied carbon associated with facilities beyond data centers, such as AWS warehouses, offices or sites run in customer facilities.

Likewise, the Scope 3 emissions associated with the end-of-life treatment of IT hardware and non-IT equipment, and the end-of-life of data center buildings, are not currently included in the model version 3.0. “We’re continuing to work on the rest of the Scope 3 emissions,” Walker told The New Stack, “and the last chunk should be available in 2026.”

In a similar way to financial amortization of CapEx, Scope 3 emissions are amortized over the assets’ service life (six years for IT hardware, 50 years for buildings) to calculate monthly emissions that can then be proportionally allocated to customers.

This amortization means that AWS can distribute the total embodied carbon of each asset across its operational lifetime, accounting for scenarios such as early retirement or extended use.

A Lack of Data for Workload Optimization

As we noted previously, estimated carbon emissions associated with the unused AWS capacity are proportionally allocated to all customers using AWS services. The other major cloud providers exclude this.

AWS has taken some flak for the state of CCFT in the past, but the underlying method is commendable and serious work, and represents a solid base; customers using the tool can rely on the data it provides.

That said, at the moment, CCFT still doesn’t give customers information that would allow them to do workload optimization.

The per-service data still isn’t broken down beyond Amazon Elastic Compute Cloud (EC2), Amazon CloudFront and Amazon Simple Storage Service (S3), with everything else lumped under “other.” Even for the services that do get broken out, that data isn’t really usable: You can’t compare Graviton to Intel, for example, or get a breakdown for GPUs.

“This will be the next area the team is digging into,” Walker told us.

Carbon Footprint Tool Case Studies at AWS re:Invent

In the meantime, it is encouraging to see AWS continuing to make more frequent releases to CCFT. “Our goal with this tool is to have a regular drumbeat of methodology updates,” Walker said, “and we are going to continue to invest and put resources into the tool.”

A post on the AWS blog, published Wednesday, stated that you will be able to hear AWS, Adobe and Salesforce talking about how the CCFT supports their environmental initiatives during AWS re:Invent in December.

“Effective decarbonization begins with visibility into our carbon footprint, especially in Scope 3 emissions,” said Sunya Norman, senior vice president for impact at Salesforce, in the AWS blog post. “Industry averages are only a starting point.

“The granular carbon data we get from cloud providers like AWS are critical to helping us better understand the actual emissions associated with our cloud infrastructure and focus reductions where they matter most.”

Readers wanting to learn more about cloud sustainability should download our free ebook, “The Developer’s Guide to Cloud Infrastructure, Efficiency and Sustainability.”