By Roger Harrabin
BBC environment analyst
Further promises by the UK government to meet greenhouse gas targets look unlikely to be met, a think tank says.
The government is striving to cut CO2 by 26% by 2020
Cambridge Econometrics was one of the first to forecast that the government would miss its target to cut CO2 by 20% for 2010.
Ministers rejected the think tank's claims for several years before finally conceding it was correct.
The latest report says at the current rate of progress this target will not even be reached by 2020.
By then, the government is theoretically striving to cut CO2 by a minimum of 26%.
The report says achieving this will need much stricter policies - particularly to tackle emissions from homes and from transport.
There is a gloomy forecast too on renewable energy - that the government will fail to meet its targets in both 2010 and 2015.
But the Department for Environment, Food and Rural Affairs said the UK had a "good record" on tackling climate change and was on target to "meet and exceed" greenhouse gas reduction targets under the Kyoto protocol.
The government's Energy White Paper and other measures meant the country was on track to meet the 2020 goal relative to 1990 levels, it said, even though the UK economy will have doubled in size in the same period.
A spokesman added: "This report does not take account of a number of these measures, such as the carbon reduction commitment and the zero carbon homes initiative, which will help us meet this target.
"We intend to put the 2020 target into legislation through the Climate Change Bill, and the Energy White Paper provides a strong foundation for a range of policies and programmes that will help us reach it."