The mayor of Rennes (Ille-et-Vilaine, Brittany) has banned the heaters from January 1, 2020, deeming them to be too polluting. Other smaller towns, such as Thonon-les-Bains (Haute-Savoie, Auvergne-Rhône-Alpes), have also outlawed them.

Four exterior gas-powered heaters running at full power for eight hours produce the equivalent carbon emissions of an average car travelling for a distance of 350km, according to figures from low carbon consultancy Carbone 4.

One Rennes restaurateur, Thomas Ruellan, told FranceInfo that the city’s heater ban would probably not make much difference to business.

He said: “We always know that winter activity is less strong, and it shouldn’t change much. It may even push customers inside and make it more inviting inside.”

But one client admitted: “I will go to bars less”, and another said: “It will affect the cool, terrace atmosphere, with your friends outside. People will have to go inside, and it’s less fun.”

Yet, another client said they would just put on an extra jumper and continue to sit outside.

A heater ban in Paris?

Jacques Boutault, mayor of the second arrondissement in Paris, is arguing that a similar ban should be applied in the capital and beyond. For the moment, there is no ban in place.

Mr Boutault said: “It’s as if you had the heating on at home, with the windows wide open. It’s illogical. We would like to ban these heaters [which operate] for a small amount of tables that are kept warm for people who would like to be outside.”

But Romain Deconquand, a brasserie manager in Paris with a significant 40m2 of outside, heated terrace, said he would not be in favour of a ban.

He said: “I would have one fewer room. If I didn’t have [this space], I would have half the seats. Half the numbers. Half the returns. Half the staff.”