The government is set to launch a review into energy tariffs that falsely claim to be green amid concerns that some firms are exaggerating their environmental credentials.
Energy minister Anne-Marie Trevelyan said 9m households are on energy tariffs that are branded as 100 per cent renewable or green, but industry figures have warned the claims may be misleading.
Energy companies are currently able to market tariffs as green even if some of the energy they supply to customers comes from fossil fuels.
They can do this by purchasing certificates that offset the use of fossil fuels, with each guaranteeing the same amount of green energy is produced.
Currently, energy firms do not have to reveal how much of their claimed green energy comes from renewables and how much comes from these Renewable Energy Guarantees of Origin certificates.
Ministers are looking at whether there should be more disclosure around the certificates and if a more robust regulatory framework is needed.
“Millions of UK households are choosing to make the green switch and more and more of our energy comes from renewables,” Trevalyn said.
“But I want people to know that when they sign up to a green tariff, they are investing in companies that make a conscious choice to invest in renewable energy.
“Part of that is ensuring companies are being as transparent as possible on where their power comes from.”
Nearly two-thirds of UK energy consumers say their purchasing decisions are influenced by how eco-friendly an energy tariff is, according to a recent YouGov poll for Scottish Power and Good Energy.
However, 75 per cent believe suppliers should be open and transparent about their tariffs, including how much of their renewable energy they buy from other companies.