Database Summary – Knowledge Centre

What Are Emission Factors?

Emission factors are key numbers used to calculate carbon emissions from the data you already have. They convert activity data (like money spent or energy consumed) into greenhouse gas (GHG) emissions, based on proxy data, allowing you to quantify the environmental impact of your business activities. 🌍📈

Example Calculations:

$20M spent on Repairs and Maintenance x emission factor = 100 tonnes of CO₂-e

1000 kWh of electricity x emission factor = 170 kg of CO₂-e

Emission factors are also called conversion factors, emission intensity, or carbon intensity. Sumday provides a database of emission factors to support your calculations when primary data isn’t available from suppliers.

Where Do Emission Factors Come From?

Emission factors are published by reliable sources, including governments, international organizations, universities, peer-reviewed journals, and company-disclosed data. Sumday primarily uses publicly available factors from reputable sources, so every factor and its origin can be transparently shared, ensuring your assessment is always audit ready.

However, you’re not restricted to Sumday’s database. If you have licensed other data or organizational-specific emission factors, you can upload custom factors in Sumday that will be accessible only to your organization.

Where Do These Databases Get Their Information?

Good question! Emission factors are generally derived from studies or economic analyses to provide high-level averages of carbon associated with different activities or goods and services. These averages are used widely in scope 3 emissions calculations, as actual supplier data is often unavailable. Sumday aims to change this by enabling clients to request actual data from vendors, improving data accuracy over time.

However, emission factors don't represent the exact emissions of a specific supplier or investment. Engaging with suppliers directly can enhance the quality of your data, and recognizing emissions reductions from their efforts can benefit your own scope 3 emissions accounting.

What data sources are available in Sumday?

A summary of key sources included in Sumday’s database are outlined below. Further information about each of the sources and associated datasets can be found by clicking on each of the sources.

Summary of Related Data Sources

Data Source Name	Data Source Description
AUS DCCEEW	The Australian Government’s Department of Climate Change, Energy, Environment and Water publish a comprehensive list of emission factors on an annual basis. The annually released dataset is titled “The National Greenhouse Accounts Factors” and is used by organisations voluntarily reporting their climate impact and is expected to be a required EF source in the upcoming Australian Sustainability Reporting Standards. In addition for Australian Large Emitters covered under the NGER Act these factors will also be used in their mandatory Scope 1 and 2 filings.
UK DESNZ (Formerly DEFRA)	The UK Department of Energy Security and Net Zero (DESNZ) releases a comprehensive list of emission factors on an annual basis as well as well as publishing supplementary emissions research and modelling. The annually released dataset is titled the “Greenhouse gas reporting: conversion factors” and is used by UK based organisations to quantify their emissions either for voluntary reporting or for entities required to report under the Streamlined Energy and Carbon Reporting (SECR) framework.
US EPA	The US Environmental Protection Agency publishes a variety of emissions factors across Scope 1, 2 and 3 with the majority of materials summarised under the EPA’s GHG Emission Factors Hub. The Hub draws from published material by the EPA and other governmental departments. The Emissions Factor Hub is used widely by US based organisations voluntarily reporting on their emissions and is a key source in the proposed mandatory reporting frameworks.
EXIOBASE	EXIOBASE is a global, detailed Multi-Regional Environmentally Extended Supply-Use Table (MR-SUT) and Input-Output Table (MR-IOT). It was developed by harmonising and detailing supply-use tables for a large number of countries, estimating emissions and resource extractions by industry. It was developed by a consortium of several research institutes in projects financed by the European research framework programs. The EXIOBASE dataset is comprised of spend based emissions factors with global coverage across 44 countries, 5 Rest of World regions and includes 200 defined product catergories. EXIOBASE is generally considered one of the most widely used emission factor datasets globally for carbon accounting purposes.
NZ ME	The New Zealand Government’s Ministry of the Environment publish a comprehensive list of emission factors on an annual basis. The suite of documents released annually is titled “Te ine tukunga: He tohutohu pakihi Measuring emissions: A guide for organisations” and is used by organisations voluntarily reporting their climate impact. In addition, New Zealand based organisations covered under the country’s mandatory climate reporting legislation also use these emission factors as part of their GHG inventories.