Measuring your carbon emissions helps you see where changes will make the biggest difference.
You don’t need perfect data to begin. Spend-based emission factors are a simple, practical way to estimate greenhouse gas emissions in your value chain (scope 3 emissions) and get started with a comprehensive carbon footprint.
By linking emissions to dollars spent in different sectors, they allow organisations to start measuring their footprint using the financial data they already have. It’s not about perfection, it’s about progress.
“Spend-based data gives you a way to build a complete picture using the data you already have,” explains Jeff Vickers, Technical Director at thinkstep-anz. “It’s especially useful for hard-to-measure areas like supply chains, particularly for small suppliers.”
From complexity to clarity
Spend-based emission factors are based on a simple idea: every dollar you spend on a product or service has an average carbon footprint. That means that you don’t need to start by asking your suppliers to track every litre of fuel they use or every tonne of concrete they lay, you can start by simply analysing your spending. Multiply your spend by the right factor, and you get an estimate of your emissions.
This approach is particularly helpful for reporting scope 3 emissions. These are the indirect emissions that happen outside of your business, but as a result of your activities. They come, for example, from making the goods and services you buy, transporting your goods or how customers use and dispose of what you sell.
Scope 3 emissions are often the most difficult to measure, yet they often make up the largest share of a business’s carbon footprint.
Spend-based emission factors are not perfect. They can overestimate emissions for expensive, low-carbon products or underestimate emissions for cheap, high-impact ones. But they provide a reliable starting point. Over time, organisations can replace spend-based estimates with more accurate, activity-based data.
Helping individuals and businesses take action
“Think of spend-based data as a doorway,” says Brian Johnston, Chief Impact Officer at Cogo. “It lowers the barrier to entry, especially for organisations that don’t have detailed data or expertise.”
Cogo, a climate-tech company based in Wellington, uses spend-based emission factors to help individuals and businesses understand and reduce their carbon footprint, often through banking platforms. Their tools translate transaction data into carbon insights, making it easier to see the impact of daily choices.
“Most people don’t know where to begin when it comes to their carbon footprint,” says Brian. “We’re making it easier for them to take the first step.”
To keep their data accurate, Cogo updates their emission factors every six months. They use thinkstep-anz’s New Zealand-specific data – which is updated annually – and apply inflation adjustments to reflect current spending and economic shifts.
A local solution with a global view
Our spend-based emission factors are tailored to the New Zealand context. Because New Zealand imports many goods it doesn’t produce (like cars, textiles and electronics), it is important to factor in emissions from international supply chains.
To do this, our spend-based emission factors combine domestic emissions data with international trade data from the Eora multi-regional input-output model. This hybrid approach gives a more complete and realistic view of carbon footprints in the New Zealand economy.
Our emission factors are available in two formats:
You’re welcome to use our emission factors in your organisation at no cost. If you want to integrate them into a carbon or sustainability tool, a commercial licence is required. The free version includes data for 2018 and 2021.
The commercial version includes data for 2022, with the next release (2023 data) due to be launched on 1 August 2025 - if you purchase now, you will automatically receive the 2023 version once it is released.