The domestic boom in flatscreen televisions could pump hundreds of thousands of tonnes of extra carbon into the atmosphere each, hampering Britain's attempts to cut emissions.
Research by the Liberal Democrats suggested yesterday that the hi-tech televisions would increase emissions by 700,000 tonnes a year by 2010 - a 70 per cent increase from Britain's 63 million television sets. The figures come amid widespread calls for changes in consumer behaviour in the wake of the Stern report on the dangers of global warming.
The research indicates that growth in sales would require power equivalent to the output of half a large coal-fired power station.
The party called on ministers to impose an energy rating on all televisions sets, along the lines of the A-G ratings already given to some household appliances.
Chris Huhne, the Liberal Democrat environment spokesman, said: "The energy used by TVs is already leading to tonnes of carbon being released every year. The energy rating scheme must be expanded, so that consumers can know how much energy each appliance they buy will use. The experience with 'white goods' suggests that labelling should work well to change behaviour, but if it does not, then the Government could also examine a charge on the purchaser of equipment that is particularly energy inefficient."
Sales of flat screen televisions have boomed as prices have fallen. But research by the Government's Market Transformation Programme (MTP), which tracks future trends, shows that current flat screen televisions larger than 24 inches use more than three times the electricity of their conventional counterparts.
There are currently 63 million television sets in the UK, which use 9.6 terra watt hours of electricity each year and are estimated to be responsible for 1 million tonnes of carbon.
The MTP estimates the number of televisions in Britain will rise to 67 million sets by 2010 - a 6 per cent increase. But the power consumed by the sets will leap to an estimated 15.7 terra watt hours - and carbon emissions will jump to 1.7 million tonnes a year.
Martin Williams, climate campaigner for Friends of the Earth, said power consumption varied between television sets, with some flat screen televisions more efficient than the equivalent older models. But he warned that the slim sets could encourage people to upgrade to larger screens.
Mr Williams backed the calls for power ratings, but urged the Government to ban the most inefficient household appliances to force manufacturers to cut power useage.