A European ban on outdoor heaters in pub beer gardens could cost the British catering and hospitality trade £250 million a year in lost trade, landlords claimed today.

Politicians in Brussels are today expected to back a resolution, put forward by a Liberal Democrat MEP, which calls on the bloc to set a timetable for abolishing goods with low energy-efficiency ratings.

The motion, although non-binding, is likely to add to the pressure for action over the heaters, which are considered wasteful because hot air being pumped out to warm up customers immediately escapes into the atmosphere.

However, a United Nations environmental expert today countered that the damage being caused by the heaters was marginal, with plasma televisions producing far more carbon dioxide.

Landlords, meanwhile, warned of serious damage to their trade if the heaters were banned. According to the Publican Market Report 2007, pubs invested up to £86.5 million on outdoor heaters in the last year to attract customers after the smoking ban obliged them to drink outdoors if they wanted to carry on smoking.

The publicans' report added that the potential long-term loss of income for pubs, cafes and restaurants which rely on an all-weather outside area to increase profits would be devastating.

It claimed that, if only 10 per cent of the UK pub trade had outdoor facilities, a patio heater ban would effectively restrict outside dining for six months of the year - costing the licensing and catering industry up to £250 million annually, or as much as £45,000 per year for a single business.

Dr Eric Johnson, National Expert Reviewer for the United Nations Framework Convention on Climate Change (UNFCCC), said the price paid in terms of global warming was small.

"The overall impact of outdoor heaters on global warming and greenhouse gas emissions is very minimal, and once you look at the domestic models used in homes, the impact is almost non-existent," he said.

"Once comparisons start with well-known offenders such as aeroplanes, outdoor heaters dwarf in comparison. In actual fact, plasma TVs produce far more CO2 than patio heaters when you compare normal usage patterns for each appliance.

"What constitutes a waste of energy is always going to be open to debate, but it is important that the public is properly educated about environmental impacts in order to make informed decisions on their everyday activities."

Dr Johnson said his environmental assessment of the damage caused by garden heaters was based on Government figures putting emissions from all domestic patio fires at 22,200 tonnes of CO2 - 0.002 per cent of the total UK CO2 emissions.

Televisions in the UK produce 4.6 million tonnes of CO2 each year and, it is claimed, on stand-by mode alone, it would take an equivalent of more than five patio heaters to produce as much CO2 as one TV does in a year.

Pub landlords echoed his calls today, claiming that heaters provided an essential service to customers following the smoking ban.

A spokesman for JD Wetherspoon, one of the UK's biggest pub chains, said: "We, like most other pub and restaurant operators, do use outdoor heaters. Especially with the smoking ban, they represent an opportunity for people to have a drink outside, particularly in the winter but also on some summer evenings which get cold.

"Our heaters are not on at all times. There is a switch by the side, and customers can turn them on and off. We do take the environment seriously, and we think the way we run our heaters is the best way. Banning them would be drastic."

Today’s energy efficiency report in the European Parliament, calling on the European Commission to prepare a timetable to phase out patio heaters, was authored by Fiona Hall, Liberal Democrat MEP for the North East of England.

It is an "own initiative" report, so has no legal force. However, it will add to the pressure for more climate change action, and will be considered by the European Commission.

The study says that urgent action is needed to introduce EU-wide minimum standards for energy efficiency covering air conditioning, television "decoder" boxes and lightbulbs, coupled with the abolition of stand-by mode on all electrical appliances, and an end to patio heaters.

The report also calls for major changes to the EU’s Energy Performance of Buildings Directive, due to be revised in 2008, and recommends much higher energy efficiency standards for new and renovated buildings of all sizes.

"We talk of the need to combat climate change with renewables, but we should never lose sight of the fact that energy efficiency is the fastest and cheapest way to cut CO2 emissions," Ms Hall said.

"With 40 per cent of the energy we consume being used in buildings, it is vital that the measures I have recommended are put in place as soon as possible."

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