22-08-08 Japan produces little natural gas, but it has a potential treasure chest of the fuel in the form of methane hydrates locked away under the ocean floor.
While that resource, found in seas or permafrost land around the world, is so far untapped, Japan aims to be one of the first countries to commercialize it by 2018, Shin Hosaka, upstream director for Japan's Agency of Natural Resources and Energy at the Ministry of Economy, Trade and Industry, told.

But Japan, which last year confirmed 40 tcf of methane hydrate in its southern Sea of Kumano, was still a few years away from choosing a site for its own development studies following pilot tests in Canada earlier this year, Hosaka said.
In the tests in March, researchers produced gas continuously from hydrates, although in "very small amounts," for six days, although much longer trials needed to be carried out before commercialization was possible, he said. "We have to keep on producing at a consistent rate for two or three months," he added.

But before Japan tests its hydrate sources, it plans a few years of investigation with the US Department of Energy starting next year, which could provide important data for its own program, the official said. In June, the two countries signed a statement of intent to jointly develop hydrates production.
First, the US must find a suitable gasfield with abundant hydrates beneath it, which most likely would be along Alaska's North Slope, Hosaka said. Hydrates there are buried about a km beneath the ground or the sea floor, he added.

The US DOE has already tested hydrates. Last year, the DOE and UK major BP drilled a $ 4.6 mm hydrate test well in the North Slope's Milne Point field to extract core samples. While performing hydrate tests with the DOE in the US, Japanese researchers will conduct their own concurrent domestic studies to find a hydrate offshore test site, he said. State-owned Japan Oil, Gas and Metals National Corporation has been tasked with the search.
"We'll decide which area is best two to three years from now," he added.

Japan's tests are expected to provide crucial information on the behaviour of methane hydrates offshore, Masato Sasaki, senior deputy director for upstream at the Agency of Natural Resources and Energy, said.
"We've never had longer-term production [tests] on land or ocean, and we have to find out the special characteristics of producing in the ocean," Sasaki said. "There are lots of unknowns."

Hydrates are ice-like deposits of water and gas trapped deep underwater where cold temperatures and extreme pressure causes the gas to condense into a semi-solid form. In Japan, hydrates in the Sea of Kumano are found about 30 km offshore in about 100 meters of water and at a depth below the seabed of 200 meters, Hosaka said, adding that the cost of a single test well runs into millions of dollars.
Japan had spent about yen 30 bn ($ 275.2 mm) since it began work on hydrates in 2001, said Hosaka. In an attempt to meet projected fuel demand, South Korea, India and Germany also have methane hydrate appraisal or test programs. Hosaka said Japan's 40 tcf of hydrates could satisfy the country's gas demand for 14 years.

Tests in March on the coast of the Beaufort Sea in the Canadian Arctic succeeded in establishing the world's first gas-from-hydrates output using the decreasing pressure system, one of two hydrate production methods. The other uses warm water to heat the hydrates to about 10 degrees Celsius, Hosaka said. In Japan, however, the warm-water system would probably not work as efficiently as using decreasing pressure, he said.
"If we try to bring warm water to southern Japan from the mainland, we'd need more energy to get it there than the hydrates would produce," he added.

While the officials said Japan's foray into hydrates testing could provide commercialization potential for industry, at least one well-known company is already tackling a type of hydrate technology.
Last year, Mitsui Engineering & Shipbuilding Company and Mitsui & Company set up a joint venture to supply hydrates from overseas fields by 2012. That venture targets small- to mid-sized gasfields overseas and aims to bring it back to Japan in hydrate form rather than LNG.