Methodology


UN Environmental Inventory

The Inventory is an annual exercise coordinated by the SUN facility of UNEP. Focal Points from UN entities report on their performance and operations. Entities submitting data follow a harmonized methodology issued by SUN. SUN collects, compiles, processes, and analyzes the data to track and present the environmental footprint of the UN system. To capture the impact of UN operations globally, the Inventory covers greenhouse gas emissions, water and fuel use, waste generation, the share of renewable electricity, and the presence of ozone-depleting refrigerants. 

The Inventory follows the GHG Protocol, covering greenhouse gas emissions under Scope 1, Scope 2, and Scope 3 (limited to business travel). All gases under the Kyoto Protocol are considered. Total GHG emissions are reported as an aggregate using the common comparable unit of carbon dioxide equivalents (CO2eq). 

Travel constitutes the largest share of GHG emissions in the UN system. Through the Inventory, UN entities reported their GHG emissions from travel using the ICAO carbon emissions calculator (Version 5.0.8). 

Electricity used in buildings is a major contributor to GHG emissions in the UN system overall. The share of renewable electricity to total electricity consumption is calculated as the kWh equivalent of all renewable electricity generated on-site or purchased. In the absence of specific renewable electricity data for purchased electricity, average values for the electricity grid of the country in which the building is located are used. 

Waste data is approached in accordance with the Framework for the Development of Environment Statistics (FDES 2013). The Global Reporting Initiative (GRI) indicators are considered methodologically regarding water and waste data. 

UN entities have field stations in multiple locations. In some cases, certain field stations of an entity report through the Inventory, while others do not. Under “reporting coverage,” we count the entities and the personnel assigned to the data-reporting field stations. 

Environmental Governance Survey 

Focal Points report on an annual basis to the environmental governance survey issued by SUN. The survey collects information on the Environmental Governance and Management Functions. It includes questions on Environmental Management Systems, Environmental and Social Safeguards, internal reporting mechanisms, senior management performance frameworks, human and financial resources and staff awareness/training to environmental management and biodiversity. 

The scope of the questions and criteria aligns with the indicators in the Sustainability Strategy I and the Greening the Blue EMS criteria which use the international standard ISO 14001:2015 as a basis. 

Annual Statistical Report on United Nations Procurement 

Procurement supports the goals set in the Sustainability Strategy I and helps 
steer providers towards more sustainable practices. The 2023 Annual Statistical Report on United Nations Procurement, issued by the Procurement Network of the United Nations Office for Project Services (UNOPS) in July 2024, is the basis for the information presented on procurement. UNOPS collects data through a voluntary questionnaire shared with all UN entities. In 2024, 30 UN entities reported based on 2023 data. 

Facility Management Survey 

For the first time this year, SUN collaborated with the International Network of Facility Managers during their Annual Conference in May 2024. Data on facility performance was collected through a dedicated survey, and opportunities for future data collection via the Greening the Blue Data platform (currently under development) were identified. Facility Managers reported on sustainability and resource efficiency interventions implemented in UN facilities over the past five years. 

Travel Survey 

A dedicated Travel Task Team, established within the Greening the Blue Community, collected information from 30 UN entities that voluntarily reported on travel policies and procedures through the survey conducted in August 2023. 

Interviews 

Throughout the year, SUN conducted interviews with seven UN entities to collect inspiring and replicable good practices. These are briefly presented in this report and covered in detail on the Greening the Blue website, as well as in a dedicated resource, Good Practices on Environmental Sustainability in the United Nations, which is issued together with the Greening the Blue Annual Report in 2024. 

SDGs Linkage 

The linkages to the SDGs are based on an analysis conducted by the Swedish Environmental Protection Agency. For this analysis, the indicators of the Sustainability Strategy I were compared to the indicators and targets of the SDGs. In the context of this report, only the connection between the various areas and the overarching SDGs is presented. 

ICAO Carbon Emissions Calculator 

The ICAO Carbon Emissions Calculator (ICEC) is the official tool for UN entities to quantify their air travel CO2 footprint, in support of their environmental commitments. The use of a common, transparent, impartial, and internationally approved methodology across the UN system facilitates the aggregation of air travel emissions data from different organizations and guarantees integrity and consistency of reported inventories. The ICEC is limited to calculating the direct emissions released into the atmosphere by the aircraft engines during a flight. There is a substantial understanding of the components of aviation climate forcing, particularly. However, important uncertainties remain in quantifying some of the aviation non- climate terms and in the underlying physical processes. As a consequence, there is not yet an international scientific consensus on whether and how to quantify these non-emissions. For additional information on the ICEC, please visit this webpage or contact officeenv@icao.int