Accelerating Innovation with the E-ledgers Accounting Method

The E-ledgers Institute is a not-for-profit learning organization advancing rigorous emissions-accounting practices to drive innovation in energy efficiency worldwide.

We advance rigorous emissions-accounting practices to drive innovation in energy efficiency worldwide.

Our founders developed the E-ledgers method for accurately and reliably tracking emissions and removals across even the most complex of supply chains in as close to real-time as practicable. We help pioneering organizations pilot the E-ledgers method, disseminating insights from these pilots, including economy-wide standards for best practice, for the world to harness.

The E-ledgers method introduces a simple, verifiable, and comparable calculation for the incurred net emissions of any product, service, organization, portfolio, or jurisdiction.

Learn About E-ledgers

Who’s Piloting E-ledgers?

See All Case Studies

Hitachi Energy

Hitachi Energy

In 2023, we partnered with Hitachi Energy and three tiers of their supply chain to analyze the E-liabilities of electrical transformers. The case study, published in November 2023, describes the counterintuitive insights from the copper supply chain and on cradle-to-gate emissions of Hitachi transformers discovered during the pilot. The accompanying video demonstrates how the Hitachi pilot calculated and analyzed the emissions data according to the E-liability method.

Read Full Study

BMW Group

BMW Group

Our most recent case study is with BMW Group, which piloted the E-liability approach on a highly customizable part of its iX range of electric cars: the radiator kidney grille. The pilot addresses a common challenge: working with suppliers who lack the capacity to calculate their embedded emissions. This article explores how BMW Group helped equip suppliers for direct emissions measurement and establish protocols to audit data at the source, ensuring data accuracy from the start.

Read Full Study

Tata Steel

Tata Steel

We partnered with Tata Steel, which is part of India’s largest conglomerate, the Tata Group, to analyze the carbon content of steel produced through various methods. The compelling element of the pilot is that Tata Steel was able to differentiate what is effectively a commodity product on emissions grounds by using product-level emissions accounting. The accompanying panel discussion dives deeper into the Tata Steel experience.

Read Full Study

Heidelberg Materials

Heidelberg Materials

Heidelberg Materials, one of the world’s leading cement producers, piloted the E-liability method focusing on a dominant contributor to cement-related emissions the conversion of limestone into clinker. By allocating real-time, batch-level emissions to cement products, the pilot demonstrated how accurate and verifiable emissions data can inform both operational decisions and customer choices.

Read Full Study

Hitachi Energy

Hitachi Energy

In 2023, we partnered with Hitachi Energy and three tiers of their supply chain to analyze the E-liabilities of electrical transformers. The case study, published in November 2023, describes the counterintuitive insights from the copper supply chain and on cradle-to-gate emissions of Hitachi transformers discovered during the pilot. The accompanying video demonstrates how the Hitachi pilot calculated and analyzed the emissions data according to the E-liability method.

Read Full Study

BMW Group

BMW Group

Our most recent case study is with BMW Group, which piloted the E-liability approach on a highly customizable part of its iX range of electric cars: the radiator kidney grille. The pilot addresses a common challenge: working with suppliers who lack the capacity to calculate their embedded emissions. This article explores how BMW Group helped equip suppliers for direct emissions measurement and establish protocols to audit data at the source, ensuring data accuracy from the start.

Read Full Study

Tata Steel

Tata Steel

We partnered with Tata Steel, which is part of India’s largest conglomerate, the Tata Group, to analyze the carbon content of steel produced through various methods. The compelling element of the pilot is that Tata Steel was able to differentiate what is effectively a commodity product on emissions grounds by using product-level emissions accounting. The accompanying panel discussion dives deeper into the Tata Steel experience.

Read Full Study

Heidelberg Materials

Heidelberg Materials

Heidelberg Materials, one of the world’s leading cement producers, piloted the E-liability method focusing on a dominant contributor to cement-related emissions the conversion of limestone into clinker. By allocating real-time, batch-level emissions to cement products, the pilot demonstrated how accurate and verifiable emissions data can inform both operational decisions and customer choices.

Read Full Study
Explore Case Studies

Launch of the Proto-Standard for Carbon Accounting

The E-ledgers Institute announced the release of a draft Proto-Standard for product-level emissions accounting and auditing using the E-liability method in September 2024. This innovative approach aims to transform how we account for emissions by tracking the cradle-to-gate emissions embedded in products and services as they move through the economy.

Our Proto-Standard

Core Conceptual Articles

Accounting for Climate Change

The first rigorous approach to ESG reporting

by Robert S. Kaplan and Karthik Ramanna

See Summary

The E-liability accounting system was introduced as the first rigorous approach to ESG reporting in an article co-authored by Professors Robert Kaplan and Karthik Ramanna and published in the Harvard Business Review (HBR). The article provides a detailed method for assigning “E-liabilities” across an entire value chain, and uses the example of a car-door manufacturer to demonstrate how this may work in practice. The article went on to win the 2022 HBR-McKinsey Award for “groundbreaking management thinking,” which in turn kicked off a series of pilot adoptions of the method by organizations around the world.

Harvard Business Review

November 2021

Read Article

Accounting for Carbon Offsets

Robust Reporting Principles to Improve Today’s Carbon-Trading Markets

 by Robert S. Kaplan, Karthik Ramanna, and Marc Roston

See Summary

Markets for carbon trading function poorly, and many traded offsets do not actually perform as promised. Without robust protocols for monitoring offsets and in the absence of proper accounting mechanisms, market-based approaches to reducing atmospheric GHG will be vulnerable to misrepresentation and fraud. Our co-founders offer E-assets as a solution, applying fundamental and well-established financial accounting principles to improve the measurement and reporting of carbon offsets. Published in the HBR, the article presents five core principles that define what constitutes an E-asset, when can such an offset be traded in arms’-length exchanges, when can the asset be used to extinguish emissions liabilities, and who bears responsibility for reporting offset impairments after the underlying assets are destroyed, for instance, due to fire or deforestation.

Harvard Business Review

July 2023

Read Article

Disclosing Downstream Emissions

When are companies accountable for customers’ use of their products?

by Robert S. Kaplan and Karthik Ramanna

See Summary

An increasing number of companies are using the E-liability carbon-accounting method as an important tool for tracking progress toward reducing global emissions in their supply chains. The system does not require formal accounting for downstream emissions – those occurring after a company sells its products to immediate customers, for several good reasons. Certain companies, however, are accountable for disclosing downstream emissions generated by consumers’ use of their products. This article presents three principles to govern accountability and explains how and to what standards of reliability the companies should disclose downstream emissions.

Harvard Business Review

July 2024

Read Article

Latest Publications and Media

See All Publications and Media

Carbon Reporting Urgently Needs Fixing — Here’s How to Do It

By Robert S. Kaplan and Karthik Ramanna

See Summary

Today’s carbon disclosures rely heavily on unverifiable, self-reported data and do not reflect the true emissions embedded in products and supply chains. In this Financial Times op-ed, our co-founders explain how the E-ledgers method brings accounting rigor to carbon reporting, enabling companies to track actual cradle-to-gate emissions in real time, differentiate products based on verified carbon content, and compete credibly on decarbonization. The article also highlights recent case studies, such as with Hitachi Energy, that show how better data can lead to smarter decarbonization decisions.

Financial Times

June 2025

Read Article

Meet the Oxford Professor Who Wants to Tear Down Scope 3 Accounting

by Jim Giles

See Summary

In this media feature, Trellis Group met with our co-founder, Karthik Ramanna, to discuss how E-ledgers accounting addresses key shortcomings in conventional carbon reporting frameworks, particularly in Scope 3 accounting. The piece covers the origins, uptake, and future applications of the E-ledgers method and its relevance in the context of carbon border assessments and industrial decarbonization.

Trellis Group

June 2025

Read Article

Join us on our mission to advance the urgent accounting upgrade needed to drive innovation in energy efficiency worldwide.

Contact Us