Carbon accounting is complex. The methodologies used to calculate emissions can vary significantly depending on carbon accountant, framework, or data source. And, while inconsistencies exist across all emissions factors, they are particularly problematic when it comes to Scope 3 emissions – the indirect emissions that occur across a company’s supply chain.

Scope 3 emissions typically represent the largest share of a company’s footprint – around 75% of total emissions on average. This, coupled with the voluntary nature of reporting for SMEs, means a significant gap exists in supply chain emissions reporting.

In short: the biggest share of emissions is the least reliable to measure.

There is also a distinct lack of harmonisation in approach. Current methods are often incomplete, inconsistent, and difficult to compare and data is collected in multiple formats, using different methodologies. This culminates in a fragmented landscape that burdens businesses with information that is rarely decision-useful.

Without reliable, comparable data:

• Businesses struggle to identify emissions hotspots and prioritise action
• Banks and corporates lack certainty around their supply chains when making financing decisions
• Governments and regulators face barriers to designing effective policy interventions because the underlying data is inconsistent or incomplete.

The importance of this high-quality carbon data is rapidly increasing too; becoming central to procurement decisions, taxation frameworks, cross-border adjustment mechanisms such as CBAM, and access to sustainable finance. And yet, the current data ecosystem is lagging behind this growing demand.

Transparent, unified and harmonised

CC was created to address this challenge. Instead of another competing standard, it will create a transparent, unified, and fit-for-purpose approach towards a harmonised methodology, and principles for calculating hybridised, system-complete, emissions factors.

If this can be accurately addressed, then the benefits could be far reaching, helping businesses manage supplier risk, tackle incoming regulatory pressures (TCFD, CSRD, CBAM, SECR), and allowing them to respond to stakeholder demands.

For SMEs, the impact could be particularly transformative. Through Perseus we’ve seen how reliable emissions data can help unlock access to sustainable finance. With its focus on Scope 3, CC could help SMEs streamline reporting requests from large customers, and provide a clearer pathway for them to participate in low-carbon supply chains.

Our approach

The solution to improving supply chain carbon accounting hinges on pre-competitive collaboration. CC facilitates this, alongside independent governance and oversight, ensuring outputs are practical, robust, comparable, and fit-for-purpose, while drawing on technical and academic expertise.

Membership

Joining CC offers organisations an opportunity to shape the future of supply chain emissions data. Benefits include:

• Helping shape a harmonised approach to emissions factors that is practical, scalable, and aligned with real-world business needs.
• Gaining early access to outputs (e.g. hybridised emissions factors) for integration into products, services, and reporting solutions.
• Staying ahead of regulatory change and influence alignment with standards, regulators, and policymakers.
• Gaining early insight into developments in carbon reporting, procurement requirements, and international mechanisms such as CBAM.
• Strengthening your organisation’s supply chain resilience and sustainability
• Supporting the creation of reliable, comparable data that enables better risk management and decision-making.

To find out more about membership and fees, reach out via cc@ib1.org

You can read the minutes of our latest Steering Group meeting here: https://ib1.org/2026/02/11/carbon-commons-steering-group-january-2026-minutes/

So what’s the difference?

Standardisation is rooted in uniformity and harmonisation in compatibility. Depending on the situation, either can offer advantages to unlocking the effective use of data. To unpack this further: 

Data standardisation is the process of bringing data into a uniform format to ensure consistency and comparability. There is a choice of bases on which standardisation may be applied. In a previous post, we identified 13, ranging from file formats to governance.

Data harmonisation is about making disparate data sets interoperable. It’s crucial when dealing with multiple datasets with varied standards as it brings these diverse data sources together into a coherent, usable whole. 

To illustrate the difference, let’s take the example of car. The way fuel for cars is refined and distributed is standardised: petrol from any supplier is expected to work in any ordinary petrol engine. By contrast, a car’s interior controls are harmonised: every car must have a way to steer, accelerate and brake but there is no single layout for how those controls are arranged.

Why harmonisation matters: lessons from TNFD

Applying this to our recent work supporting the Taskforce on Nature-related Financial Disclosures (TNFD), we can see why harmonisation is often essential. TNFD asked us to help develop their global data strategy and a set of principles for nature data. Early on, it became clear that nature data could not be reduced to a single standard because it spans water, soil, species, forests, and many other systems, each with its own metrics and methodologies. 

In a fragmented landscape like this, harmonisation serves as the connective tissue. It allows decision-makers to interpret nature-related risks, opportunities, and impacts through a more integrated view.

The benefits of harmonisation

Improved Decision-Making: Harmonised datasets offer a broader, richer, but still integrated view, enabling better-informed choices, particularly when decisions draw from multiple data sources.

Reduced Friction: Organisations can continue using the tools, formats, and definitions that work for them, while still contributing to an interoperable system.

Faster Collaboration: Harmonisation enables a shift from ‘agreeing on one way of doing things’ to ‘doing one thing well’, encouraging a focused, practical use-driven approach that drives alignment.

Why harmonisation fits IB1’s approach

These benefits are what makes harmonisation a natural fit for IB1’s use-case driven approach. In our Open Energy work, as we explore effective data-sharing use cases for the energy sector, we’re facilitating cross-sector collaboration with Distribution Network Operators (DNOs), regulators, and other stakeholders in the sector. Each has its own definitions, terminology, and internal standards. So how do they all agree on a common language? 

The answer is, they don’t, and they don’t need to. Expecting them to adopt one common language is unrealistic, time consuming and unnecessary. This would be a standardisation-first approach. Useful in some contexts, but often slow, costly, and difficult to achieve at scale. Instead, the approach is to pick a real-world use case and harmonise our approach across multiple stakeholders and data sets. Use cases give our working groups a practical focal point, allowing collaboration to form around specific needs. 

“We prefer to harmonise through utilisation and application rather than theorise and wait for a standard to be implemented”

Gavin Starks, CEO, IB1 at the Open Energy webinar. 

So when does standardisation have a part to play? 

Standardisation creates stability and comparability where consistent reporting is essential. For instance, this was the recommended approach in our Impact Investing report for COP28, where we advised organisations to require data-backed, standardised environmental reporting from their supply chains. This is crucial for decarbonisation and for accurate Scope 3 emissions reporting because stakeholders, consumers, investors and employees increasingly expect businesses to provide a full and trustworthy account of their value-chain emissions. 

Data standardisation, in this context, is the right way to go because it establishes a common baseline that ensures everyone is measuring and reporting emissions in the same way, enabling meaningful comparisons, credible disclosure, and targeted action.

Ultimately, harmonisation and standardisation both have roles to play. But, often in our work we encounter multi-stakeholder projects, with disparate data sets that require a harmonised solution. By grounding decisions in real use cases we’re able to find cross-sector solutions to real-world problems.