Climate change and its side effects are the most pressing things that face the planet according to the 750 global experts and decision-makers polled for the World Economic Forum’s 2020 Risk Report. Thankfully, there is a way we can avert disaster and that is to reduce greenhouse emissions.

All this bad news may account for the fact that 85% of people in the UK support the use of renewable energy (according to the annual public attitudes tracker published by The Department for Business, Energy and Industrial Strategy in 2019).

But green energy can seem confusing for first time buyers. Firstly, what even is green energy?

What is green energy?

The official term for green energy is renewable energy sources. It is renewable because it is collected from sources, such as wind and the sun’s rays, which are naturally replenishing. Unlike fossil fuels, such as coal, where once you’ve burnt it you have nothing but ash and carbon dioxide (not to mention other nasties, like particulate matter, nitrogen oxides, and toxic chemicals). Demand has risen over the years for suppliers who source from green energy:

“On the back of this rise in demand, many more energy suppliers now offer green tariffs. In fact, our research shows that 54% of tariffs on the market in April 2021 were green compared to 40% the same time last year.”

From Forbes Advisor’s Best Green Energy Suppliers Page

The main ‘renewables’ are wind power (on-shore and off-shore), solar power, wave and tidal, biomass, hydroelectric, and geothermal. Although nuclear power does not produce carbon dioxide and is hailed as a green, low carbon lifeline by some scientists, the fact that it produces nuclear waste means it is not traditionally classed as ‘green’.

Buying your energy from a green energy supplier does not mean you will get all your energy from renewable sources. The National Grid electricity network connects all power stations, so your electricity will come from that pooled network.

You can buy ‘green gas’, also known as biomethane, which is made as a byproduct of anaerobic digestion plants and from landfill, and there is also syngas made from biofuels. Before you buy, make sure your provider is a member of the Green Gas Certification Scheme. Green gas is also mixed with normal ‘natural gas’ when you receive it, as with electricity from the National Grid.

As the UK does not produce enough green gas to supply all those who want it, most companies offer carbon offsetting as an alternative to green gas. Under these schemes you receive natural gas (that does emit carbon dioxide when burnt), but the company ‘offsets’ your carbon footprint by investing in projects that reduce will your carbon footprint in the future.

Who offers green energy?

There are a number of smaller companies that only provide green energy, while the larger companies – including the Big Six – have deals that offer 100% green energy.

List of the UK’s 100% green energy suppliers

CompanyCompareFuel MixExit Fee
Bristol EnergyCompare TariffsElectricity and 15% green gas, the rest offsetNo
BulbCompare TariffsElectricity and some green gas and some offsetNo
Co-operative Energy (now a part of Octopus Energy)Compare TariffsElectricity and carbon offset gas + Community EnergyNo
Ebico (in partnership with Robin Hood Energy)Compare Tariffs Yes
EcotricityCompare TariffsElectricity and carbon offset gas (with a green gas mill in the works)No
Foxglove EnergyCompare TariffsElectricity only 
Good EnergyCompare TariffsElectricity and 10% green gas – 90% offsetOn fixed price deals
Green Energy UKCompare TariffsElectricity and 100% green gasNo
Green Star Energy (Now part of Shell Energy)Compare TariffsElectricity and carbon offset gas 
Gulf Gas & PowerCompare TariffsElectricity and carbon offset gasYes
Octopus EnergyCompare TariffsElectricity and carbon offset gasNo
Outfox the MarketCompare TariffsElectricity only 
People’s EnergyCompare TariffsElectricity onlyFixed yes, Variable no
Pure PlanetCompare TariffsElectricity and carbon offset gasFixed yes, Variable no
Robin Hood Energy (a not-for profit social enterprise)Compare TariffsElectricityNo
So EnergyCompare TariffsElectricity onlyNo
SymbioCompare TariffsElectricity only 
Tonik EnergyCompare TariffsElectricity and 10% green gas – 90% offset (optional) 

Who are the best green energy suppliers?

Each year the consumer magazine Which? surveys the top UK energy suppliers. In 2020 they asked more than 8,000 energy customers for their opinion on how the energy company they use measured up on a number of points, including bill accuracy, customer service and value for money. The survey covered 35 suppliers in Great Britain and six in Northern Ireland. Three providers earned the award for Which? Recommended Provider, they all happen to only provide renewable energy. The winners are:

The runner-up:

  • Ebico (a green not-for-profit social enterprise)

How much green energy does the UK produce?

The world’s first coal-powered power station was built in the UK in 1882 (the Holborn Viaduct power station), but how has the country been doing since the world started ‘decarbonising’? Broadly, the news is good and getting better.

Renewables made up 36.9% of UK electrical power over 2019. Low carbon energy (which is renewables combined with nuclear energy) made up 54.2% of all UK electricity. Within this mix, renewable power generation increased by 8.5% from 2018, while nuclear reduced by 13.6%.

Gas continues to be the UK’s largest source of energy. This is a fossil fuel, but it releases fewer green house gasses into the atmosphere than coal or oil. Over 2019, gas accounted for generating 40.9% of UK electrical power. Coal, on the other hand, accounted for only 2.1%. In 2010, coal accounted for a higher percentage of the country’s energy supply than renewables. And the UK is planning much more investment in renewables, especially off-shore wind.

What is the mix in UK renewable power generation?

 teraWatthours (TWh)*% change on a year earlier
Onshore wind32.2+6.6
Offshore wind31.9+19.6
Solar PV12.7-1.4
All renewables119.3+8.5

* One teraWatthour (or tWh) is a billion kiloWatthours.

All figures according to the Department for Business, Energy and Industrial Strategy UK Energy Statistics for 2019 statistical press release.