The largest currently operating geosequestration projects – roughly 1 million tonnes per annum each – are in the North Sea (run by Norwegian company Statoil) and Algeria (BP).

An official from the Japanese ministry of economy, trade and industry, Masahiro Nishio, told Associated Press the country could have a geosequestration program in operation as early as 2010, but extensive research would be done first in an attempt to reduce costs.

Using current technology, Japan estimates CO2 geosequestration could cost as much as $A70.40 per tonne. Nishio said Japan would conduct research with a view to halving this cost by 2020.

Japanese industry is said to produce up to 1.3 billion tonnes per annum of CO2 emissions, and Nishio said the geosequestration initiative would initially focus on natural gas production, liquefying the CO2 for geological storage.

There are concerns about the long-term success of any geosequestration project, with the risk of leakages due to geological activities, although existing projects have not yet reported any leakages.

Edinburgh University carbon storage researcher Stuart Hazeldine told British newspaper the Guardian that the biggest problem facing Japan's long-term plans was likely to be a lack of reservoirs large enough to make the scheme practical.