Fuel Mix Disclosure Guide

Compare the mix of fuels energy companies use to supply electricity

In the United Kingdom, all energy suppliers are legally obligated to disclose to their customers their fuel mix. This is the mix of fuels (gas, coal, nuclear, etc.) used to produce the electricity they supply to their customers

In addition, consumers must be informed about the amount of carbon dioxide emitted via electricity generation and /or the quantity of nuclear waste produced.

Fuel Mix Disclosure format

The format of Fuel Mix Disclosure is set out in The Electricity (Fuel Mix Disclosure) Regulations 2005. It requires the information to be disclosed in tables as percentages, so it is easily understood by anyone accessing it.

The environmental impact data, relevant to Paragraph 11 of the Regulations, is to be described in g/kWh.
Here are examples of Fuel Mix and Environmental Impact Disclosure:

Fuel mix (%)

Coal 8.9
Natural Gas 60.3
Nuclear 18.1
Renewables 8.9
Other Fuels 3.8

High-level radioactive waste

0.007 g/kWh

Carbon Dioxide Emissions

Energy Source g/kWh
Coal 920
Natural Gas 349
Nuclear 0
Renewables 0
Other 871
Overall average 208


Energy Companies' Fuel Mix

To easily compare the mix of fuels used by energy companies, please refer to the data below. We have calculated the percentage of renewable vs. non-renewable sources so you can determine the best supplier for you.  If you are interested in going with a 100% renewable energy supplier then you can check out our Guide to Green Energy Companies.

British Gas Fuel Mix

E.On Fuel Mix

EDF Energy Fuel Mix

nPower Fuel Mix

Scottish Power Fuel Mix

SSE Fuel Mix

Corona Fuel Mix

Engie Fuel Mix

Gazprom Fuel Mix

Octopus Energy Fuel Mix

Opus Fuel Mix

Utilita Fuel Mix

*The data above has directly been sourced from the supplier's websites.

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