Ecotricity declared one of Britain’s greenest energy companies in Which? study

30 September 2019

Ecotricity have been declared one of the greenest energy suppliers in the UK by Which?, after their study found that many so-called ‘green’ energy companies aren’t as environmentally friendly as they appear.

Which? found that more than a third of energy customers believe that by being on a ‘green’ or ‘renewable’ tariff, they’d get 100% green energy supplied direct to their home. And 11% expected their supplier to generate some of the renewable energy it sells.

But with over 355 green energy tariffs currently on sale in the UK, only four energy companies surveyed told Which? that they own renewable generation, like wind or solar parks.

While Ecotricity supplies renewable energy and uses customers’ bill money to invest in new forms of green energy, many UK suppliers get their green status by buying REGO certificates.

A REGO certificate (Renewable Energy Guarantee of Origin) is issued to energy generators by Ofgem for every megawatt hour (MWh) of renewable power they put into the grid. The more green energy they generate, the more REGO certificates they get. 

When they sell that energy on to a supplier, they sell the REGOs along with it, so the supplier can prove the energy it supplies is green. But suppliers can also buy REGOs without buying the energy itself. They could buy fossil fuel energy and, as long as they buy enough REGOs to match that energy, they can all themselves green.

Light green energy suppliers can buy REGOs to match the renewable energy already put back into the National Grid to what their customers use – so they can buy ‘green’ status without investing in renewable energy, for as little as £1.55 a year.

Our founder, Dale Vince, explains how ‘light green’ firms selling 100% renewable power backed only by REGOs, “gives the illusion of greenness to customers, which can be misleading”.

By switching to Ecotricity, you can be sure that you’re supporting green energy production and tackling the climate crisis with your energy bill.

We were the first company in the UK to declare a climate emergency. We supply 100% green electricity and carbon neutralised gas. And we use our customers bill money to build and maintain clean alternatives to fossil fuels.


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