ASA allows Ecotricity’s “greenest in Britain” claims

The green energy firm Ecotricity can claim to be Britain’s greenest energy company after a complaint made by Tesla in respect of various claims on the Ecotricity website was not upheld by the Advertising Standards Authority (ASA).

Ecotricity had included a number of claims on its website including “Britain’s Greenest Energy” and “The electricity we supply is the greenest of any company in Britain”. Electric car manufacturer Tesla Motors challenged whether claims that Ecotricity supplied “the greenest electricity” and “the greenest energy in Britain” were misleading and could be substantiated.

In response Ecotricity submitted technical data illustrating their carbon dioxide emissions as a result of the various sources of energy through which they supplied electricity, including coal, natural gas, nuclear and renewables. They compared their emissions with those of the “Big Six” utility companies and six other suppliers that were their commercial competitors, including one other competitor who also provided electricity which came from 100% renewable sources. The data demonstrated that Ecotricity’s emissions were lower than those of their competitor.

Ecotricity also said they were the only supplier to provide “green gas”, and provided evidence which demonstrated that their green gas had been certified. They compared the carbon footprint of their own green gas to the norm, which was 100% fossil fuel derived. Again, the emissions figures for the green gas were lower than for fossil fuel derived gas.

Ecotricity therefore believed they had substantiated their claims that they supplied the greenest energy in Britain, and the claims were not misleading.


The ASA stated that “the claims that Ecotricity supplied the greenest electricity in Britain were absolute ones which required substantiation to show that it was more environmentally friendly than any other provided in the UK”. They found that the companies and sources Ecotricity compared their emissions with were “appropriate and relevant”.

Overall, the ASA considered “Ecotricity had demonstrated that its electricity and green gas had the least impact on the environment compared to their competitors”, and therefore concluded the claims that they supplied the greenest energy in Britain had been substantiated and were not misleading.

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