The amount of methane hydrates in our marine sediments is reported about 4.65 to 7.35 trillion cubic meters. Our yearly natural gas consumption is 820 billion cubic meters. Japan national research succeeded to demonstrate methane hydrate recovery in Canada by the depressurization method. A demonstration in Nankai trough is planned for the next step. CRIEPI has proposed a methane hydrate enhanced recovery method by using exothermic heat of CO_2 hydrate formation to improve the productivity and the recovery factor. This enhanced recovery can be adapted for sediments less than 10 degrees centigrade. The number of the sites is two-thirds of the founded sites in the world.
