National and corporate/facility level GHG inventory systems can help countries address climate change. However, these systems are often developed independently of each other, and confusion exists regarding the purpose of and need for each inventory type. This working paper seeks to describe national and corporate/facility GHG inventories, highlighting major differences.

The paper also explores potential inventory system linkages to support the efficient use of country resources.

Key Findings

An effective climate change strategy for a country, corporation, or facility requires a detailed understanding of GHG emissions sources, quantities, and trends over time. An inventory is the tool to provide such information. It allows both governments and companies to take into account their emissions-related risks and opportunities and focus efforts on mitigation activities that can produce the greatest GHG reductions.

National inventories and corporate/facility inventories each fulfill unique roles: for example, while the former track a country’s total emissions, the latter allow individual companies or facilities to assess their emissions performance. Further, corporate/ facility reporting programs can provide localized information on the most significant emissions sources and emissions trends. Despite important differences in category definitions, methodology, and other elements, governments interested in developing (or enhancing) a national inventory system and corporate/facility reporting program should seek to capitalize on possible linkages between the two systems. In this paper, we have identified two potential areas for linkages: (1) integrating source data into the national system to improve completeness and accuracy; and (2) sharing institutional resources, technical expertise, and data systems to build on existing capacities and get the most from limited resources.

Proactively identifying and exploiting these and potential other linkages between national inventory and corporate/ facility reporting systems can bring enhanced benefits, such as greater consistency across national datasets, formalizing the role of data from corporate/facility inventory systems in the national inventory system, and maximizing data collected and analyzed. Establishing such linkages will continue to be critical in improving the quality of inventories, increasing their utility for mitigation strategies, and reducing emissions at both the national and corporate/facility level.

Executive Summary

Inventories of greenhouse gases prepared at the national level and at the corporate/facility level can complement each other and help decision-makers understand emission trends and inform mitigation activities, among other functions. Most countries already have at least some experience preparing national inventories and may have also developed a national inventory system. At the same time, corporate/facility reporting programs are becoming more prevalent. However, the two systems are often developed independently of each other, and as a result countries are unable to capitalize on potential linkages between them. Moreover, confusion often surrounds the purpose and need for corporate/facility inventory programs when data are already being collected and disclosed for national inventories.

This working paper describes national and corporate/facility inventories and outlines the various roles they can play related to emissions measurement, management, and policymaking. It also discusses corporate/facility reporting programs and compares national and corporate/facility inventory systems to highlight their differences. It then explores possible linkages between corporate/facility programs and national inventory systems. These linkages include the use of source-level data from facilities to improve accuracy and/or provide validation to national emissions estimates as well as the use of existing institutional and technical capacities, likely associated with developing a national inventory, to support a corporate/facility reporting program. Utilizing these linkages can enhance the quality of information provided in both national and corporate/facility inventories, thus strengthening the foundation for subsequent mitigation efforts. The linkages discussed could facilitate efforts to reduce emissions in countries with competing demands within a mitigation program and limited resources.