Japan has moved closer to unlocking a potential new energy source, after a research group extracted methane gas from frozen undersea deposits for the first time.

Japanese officials hope the achievement, in a test conducted off Japan’s central Pacific coast, will win their resource-poor nation a measure of energy independence. It was announced a day after the second anniversary of the Fukushima earthquake, tsunami and nuclear crisis that crippled the country’s atomic power industry and exposed its lack of domestic energy sources.

The Japan Oil, Gas and Metals National Corporation said yesterday it had successfully extracted gas from deposits of methane hydrate, a hyper-abundant mix of frozen water and methane sometimes called “fire ice”. Countries including the US and Canada are also conducting research on methane hydrate, which experts say is at least twice as plentiful as all known reserves of natural gas.

Prospects for commercial extraction remain far from certain. But Ryo Minami, director of the oil and gas division at Japan’s Agency for Natural Resources, compared methane hydrate to shale gas, the once-marginal resource which is transforming the US energy market:

With virtually no conventional fossil fuels of its own and a nuclear industry crippled by Fukushima, Japan has been keen to develop sources of energy, however speculative. The methane trapped in the Nankai trough could replace up to 11 years of LNG imports.