Carbon budget

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Scales representing the balance of carbon budgets

A Carbon Budget is the maximum amount of greenhouse gases (CO2e) that can be released into the atmosphere whilst having a reasonable chance of limiting global warming to a specific target.

The science for carbon

The science is based on the principle that every tonne of CO2e emitted into the atmosphere increases the global temperature by a certain amount. This relationship is approximately linear, which means that if we want to limit global warming to a certain level, we can calculate the total amount of CO2 that can be emitted into the atmosphere.

This total amount of permissible CO2 emissions is the Carbon Budget. It is a finite amount, which means that once the budget is met, any additional CO2 emissions will lead to global warming beyond the target.

The UK’s carbon budget

The Climate Change Act 2008 requires the government to set five-yearly carbon budgets, after taking advice from the Climate Change Committee. These run until 2032. These budgets are fixed in advance and set five-year caps on the total greenhouse gas emissions allowed to ensure the UK meets its emissions reductions commitments.

The latest carbon budget delivery plan was published in 2023.

The fifth budget limits the UK’s annual emissions to 57% below 1990 levels by the year 2032.

Business carbon targets

For a business the carbon budget for their business is the annual amount of greenhouse gas emissions produced by the operation of the business to align with their sustainable business targets in their carbon reduction plan.

Carbon budgeting requires a detailed understanding of your business’s carbon footprint and the sources of the CO2e emissions. It also requires a commitment to reducing emissions and a plan for how this will be achieved by changing the way they operate. This can involve a range of strategies, from energy efficiency measures to changes in production processes, supply chains, and even business models. However, it also presents opportunities for innovation and growth.

Scales and balancing carbon budgets

Setting your website’s carbon budget

For businesses, setting a budget for a website can be very helpful when designing and developing a sustainable website.

By measuring the carbon footprint of each page view and then setting a maximum budget per page the website and marketing team can focus their efforts on the pages with the greatest carbon footprint. They can then contribute to their organisation’s carbon reduction plan.

When planning marketing campaigns it is also possible to set a campaign budget by measuring the carbon footprint of campaign landing pages and estimating the number of visits for the campaign. Optimising these pages before the campaign starts will help to reduce the overall carbon footprint for the campaign.