The government is ready to consider introducing personal, tradable carbon allowances, the environment secretary will say this evening, as part of its efforts to persuade members of the general public to reduce their energy consumption.
The move has been described as "a good idea whose time has not yet come" by environmental campaigners. They argue that it is premature to shift this kind of responsibility onto consumers who still have very little choice about the kinds of energy they use.
Environment secretary David Miliband said the scheme would cover people's use of electricity, gas, petrol and air travel. He argued that a trading scheme would be fairer than tax increases, because only those who exceeded their allowances would have to pay.
The idea is that everyone would be set a carbon ration. Those who chose to reduce their emissions could then sell the excess to other people.
However, Charlie Kronik, head of Greenpeace's UK climate team, says personal action, like this, works best when you have a real choice.
He accused the government of sending out mixed messages, pointing out that on the one hand it is encouraging growth in the aviation sector by expanding airports, and refusing to consider taxing aviation fuel, but on the other hand, it wants people to reduce their emissions to combat climate change.
The problem must be tackled at a system level first, he told us. Take road use, for example:
"The government needs to work hard to introduce EU-wide fuel efficiency legislation so that the fleet as a whole becomes more efficient. This would offer people a choice of vehicles - beyond the Prius - that would be more fuel efficient.
"A personal trading scheme now is shifting the responsibility to the individual, without offering them a choice," he said.
A spokesman for Defra said that carbon trading is an idea very much with the long term in mind, but acknowledged that the UK has some way to go on dealing with the emissions from surface transport.
"It needs carrots and sticks," he said. "We need to continue educating peope to have more sustainable lifestyles. We need to change attitudes and behaviours."
He said that for many people, although they are aware of climate change as an issue, they thought it was something too vast for them to make a difference, and that it should be left to government and industry.
Miliband is set to speak this evening at the Audit Commission's annual lecture. He will say that the scheme would give people who want to "do their bit" for the environment a way to "guide their decisions".
The scheme is only one of a number of measure the government is considering. Other approaches that it might take include Carbon loyalty cards, league tables, the use of carbon offsets at point of purchase, and carbon labeling on goods. ®