4. A Scope 3 assessment is designed to fit your company.
One of the most thorough methodologies for measuring the environmental impact of a product, service, or industrial process is a life cycle assessment (LCA). It can be used for not only calculating GHG emissions, but also a range of other factors, such as material recoverability and water use. However, depending on the design and boundaries of the study, a typical LCA can be expensive, especially for SMEs. LCAs are also highly specific, usually focusing on a single product, service, or industrial process.
A Scope 3 assessment, in contrast to an LCA, is broader and less cost-intensive. An LCA considers multiple environmental impacts, but a Scope 3 assessment is concerned solely with GHGs. While quantifying only emissions may seem simpler, it can be difficult at Scope 3 because a firm needs to track back to activities or assets they do not control. Assessors can untangle some of this complexity using the GHG Protocol’s framework and the EPA’s Emissions Factors Database; both are publicly available and easily accessible to individuals without LCA expertise.
The GHG Protocol publishes a technical guide for measuring Scope 3 emissions in corporate value chains. It includes 15 categories that correspond to activities up and down a company’s value chain. Each category is given strict boundaries to make it easy to understand exactly what needs to be measured, and what data needs to be collected.
Importantly, the GHG Protocol assessment is designed to be tailored to a business’s unique circumstances. Is it a manufacturer? Is it a service-based company? In practice, any one company will use a mix of the 15 categories. Each category requires the analysis to follow one or more of four pathways: supplier-specific, hybrid, average-data, or spend-based.
The GHG Protocol assessment is designed to be tailored to a business’s unique circumstances.
The purpose of the EPA’s database, which is regularly updated, is to ease an assessment through the use of aggregated, generalized factors for common processes and products. For example, it can be used to find the GHGs emitted per mile by a passenger car made between 2007 and 2020 running on diesel, or to determine how much carbon is emitted when a short ton of corrugated containers is landfilled.
The shape of a single Scope 3 assessment is unique to the company performing it. As has been shown above, there is substantial leeway for selecting the right measures and tools to make sure that it results in information that is both useful and actionable. It is also worth noting that, as the demand for Scope 3 assessments increases, more resources will become available to businesses.