Plans to limit energy use by giving everyone an individual carbon allowance are being considered by the government.
People would buy and sell carbon ration
The "domestic tradable quotas" scheme could help the UK comply with the Kyoto Protocol, think tank the Tyndall Centre for Climate Change Research suggested.
The plan would see people issued carbon units - each equivalent to 1kg of greenhouse gases - to use when buying products such as flights and petrol.
A government spokesman said plans were at the earliest stage of consideration.
Environment minister Elliot Morley told the Daily Telegraph the government could "think the unthinkable".
The scheme would see people and businesses able to buy or sell extra rations.
Under their plans the total national carbon allowance would be steadily reduced to reach the government target of cutting CO2 emissions by 60% by 2050.
Mr Morley said: "We should have an open mind about the kind of levers that we apply and not be afraid to think the unthinkable.
"It is fair to say that for a lot of people personal carbon allowances falls into the unthinkable category.
"I don't think we should dismiss these approaches. There might be a decade of debate in it before we get anywhere with it, but my job is to consider quite radical new approaches."
The Department for Environment, Food and Rural Affairs spokesman confirmed the scheme was being investigated but said the process was at the earliest exploratory stages.
It was recently revealed that the UK's emissions of greenhouse gases rose between 2003 and 2004.
The emissions last year were 1.5% above those in 2003 and are now higher than at any time since the Labour government came to power in 1997.