Things are so bad the Energy Saving Trust is calling for shops to stop selling the luxury gadgets.

“We are calling on responsible retailers to reconsider the sale of patio heaters in light of the substantial amount of emissions they produce. Why don’t people just wear a jumper?” said Philip Sellwood, chief executive of the Energy Saving Trust.

Sellwood said sales of patio heaters were also up in the commercial sector, which had the potential to do more damage.

“A third of pubgoers choose a pub where there is a patio heater and landlords are helping make them desirable, which they are not.” Sellwood said.

However, with the recent introduction of a smoking ban inside all UK pubs the outside areas have become very desirable to those not willing to kick the habit.

The Energy Saving Trust said it expects the number of domestic patio heaters to double in the next 12 months to 2.3 million.

Sellwood said that would produce the same amount of C02 as 200,000 cars driving from John O’Groats to Land’s End.