At a summit in Japan two years ago, eight of the world's leading economies backed an International Energy Agency goal to launch 20 large-scale projects to demonstrate carbon capture and storage technology by 2010.
In fact there were only five such projects in operation, all commissioned before the 2008 summit, said the energy adviser to 28 developed countries ahead of next week's G8 summit in Canada.
None of those existing projects tested the full chain of CCS processes, which involves trapping and then piping and storing underground carbon emissions from coal and gas power plants.
"(The 2010 goal) remains a challenge and will require that governments and industry work in concert," the IEA said in a report to the Canada G8 summit.
One new Australian project had launched, however, and was proceeding to construction to test the full CCS process.
Also on a positive note, the IEA estimated that governments had committed over the past two years to provide over $26bn in funding support for demonstration projects. That compares with an annual funding need of between $5bn and $6.5bn over the next decade.
The IEA argues that CCS is a vital technology to fight climate change because it could allow developing countries to continue to burn supplies of cheap coal and still curb carbon emissions, as they try to grow their economies. Developing countries are now the main global source of rising greenhouse gas emissions.
The IEA estimates that about 100 CCS large-scale projects are needed worldwide by 2020, about half in developing countries, to stay within safer limits of climate change.
The report calculated that governments are committed to support between 19 and 43 large projects by 2020, and cited other estimates of about 80 projects at various stages of development.
"Much greater effort will be needed to meet future deployment levels," it said.