Carbon calculator

The MacKay Carbon Calculator provides a model of the UK energy system that allows you to explore pathways to decarbonisation, including net zero by 2050.

Using the MacKay Carbon Calculator, you can create pathways to find out how we might reduce the UK’s greenhouse gas emissions to net zero by 2050 and beyond. You choose your ‘levels of ambition’ for decarbonising different parts of the energy system, and the calculator then shows how your choices affect UK emissions expressed as ‘carbon dioxide equivalent’ (CO2e).

Its purpose is to help everyone engage in the debate. It also allows government to explore how its plans support the path to net zero.

The calculator is named in honour of the late Sir David MacKay who was the driving force behind the first UK 2050 calculator:

Tribute to Sir David MacKay (PDF, 85 KB, 2 pages)

The MacKay Carbon Calculator

There are 2 online versions of the calculator, a universal version called My2050 and a detailed version.

Both versions contain levers of decarbonisation, 15 in My2050 and 45 in the detailed version. You select your level of ambition of decarbonisation effort using the levers, ranging from Level 1 - minimal effort, to Level 4 - maximum effort. Popup descriptions explain what the levels represent in terms of behavioural change or infrastructure investment. We will publish a user guide for the detailed version here shortly.

The calculator results are based on scientific data. This Excel spreadsheet provides more information about the model used by the online versions of the calculator:

MacKay carbon calculator (Excel version) (XLSM, 13.4 MB)

The levels of ambition

The levels of ambition are based on views expressed by over 100 expert stakeholders, including academics, non-government organisations, industry bodies, operators and consultants. They don’t reflect government policy but can be used to represent policy.

Teacher resources

Teacher resources for My2050 (Key Stage 4) and the detailed version (Key Stage 5), developed with the Royal Geographical Society, are available from the RGS website.

The project

The MacKay Carbon Calculator project is a collaborative project between BEIS and 4 main partners, Energy Systems Catapult, Climate Media Factory, Cambridge Architectural Research (CAR) and Climact.

Contact us

If you have any comments or questions, please contact

Published 3 December 2020