Unraveling the Labyrinth: A Pragmatic Walkthrough for Determining Emissions from the Most Challenging Scope 3 Emission Classes
In the quest for reducing greenhouse gas (GHG) emissions, organisations are increasingly focusing on Scope 3, which encompasses indirect emissions from upstream and downstream activities in their value chain. Three key categories that require particular attention are Purchased Goods and Services (Category 1), Use of Sold Products (Category 11), and End-of-Life Treatment of Sold Products (Category 12).
Category 1: Purchased Goods and Services
To accurately calculate Scope 3 emissions in this category, organisations can employ supplier-based data, spend-based estimates, or a hybrid approach. The supplier-based method involves collecting primary emissions data directly from suppliers about the goods or services they provide, offering the highest accuracy but requiring extensive supplier engagement and data collection. The spend-based method, on the other hand, is less precise but simpler, multiplying the monetary value of purchased goods or services by emissions factors derived from economic or sector-specific averages. A hybrid approach combines both methods, improving accuracy while managing data gaps.
Category 11: Use of Sold Products
Calculating emissions in Category 11 necessitates a life cycle analysis, focusing on the emissions associated with the product’s use phase. Emissions are calculated based on typical product energy use or fuel consumption over its expected lifespan, multiplied by appropriate emission factors representing the end-user's energy source or fuel type. To increase accuracy, detailed data on product usage patterns and material composition, coupled with carbon factors covering the use phase, should be used.
Category 12: End-of-Life Treatment of Sold Products
Emissions in Category 12 are calculated through life cycle assessment models that consider the disposal methods (landfill, recycling, incineration) and the related emission factors for each treatment. Accurate estimation requires data on product material composition, reuse/recycling rates, and typical waste management practices in the regions of disposal.
Common Calculation Methods & Tips for Increasing Precision
- Prioritise collecting primary data from suppliers and customers rather than relying solely on sector averages or economic proxies.
- Utilise Lifecycle Assessment (LCA) tools to model emissions throughout the full product life cycle from raw material extraction through use and disposal phases.
- Segment data by product type, supplier, geography, and disposal method to reflect variations in emissions profiles.
- Apply the hybrid approach for situations where data availability varies across suppliers or product categories, integrating both primary and secondary data sources.
- Regularly update emission factors reflecting the latest regional, sectoral, and technological changes to maintain accuracy.
- Engage with supply chain partners to improve data transparency and develop standardised reporting.
In summary, increasing precision in these complex Scope 3 categories requires combining supplier-specific data, life cycle assessments, and regionalized emission factors while supplementing gaps with spend-based or industry average data as needed. The GHG Protocol and its latest guidance provide detailed frameworks and examples to support these calculations.
[1] GHG Protocol, 2021. Corporate Value Chain (Scope 3) Standard: 2021 Edition. World Resources Institute and the World Business Council for Sustainable Development. [2] UNEP, 2013. Tools for the reduction of greenhouse gas emissions in transport: A guide to carbon footprinting. United Nations Environment Programme. [3] Carbon Trust, 2016. Carbon Trust Standard for Scope 3: Guidance for calculating your Scope 3 emissions. Carbon Trust.
In the realm of environmental science and industry, accurate calculations of Scope 3 emissions in categories like Purchased Goods and Services (Category 1) may be achieved through supplier-based data, spend-based estimates, or a hybrid approach. Conversely, for Category 11 (Use of Sold Products), a life cycle analysis is essential, focusing on emissions associated with the product’s use phase and employing detailed data on product usage patterns and carbon factors. Lastly, in Category 12 (End-of-Life Treatment of Sold Products), precise emissions calculation demands life cycle assessment models capturing disposal methods and related emission factors. To enhance precision, resources such as Lifecycle Assessment (LCA) tools, primary data, and regionalized emission factors can be utilised while addressing data gaps with spend-based or industry average data.
