Japan Is Banking On Ice That Burns

TOKYO -- Like ice that burns, methane hydrate is cold, white and would light up like a gas stove if held to a flame. And so much of the frozen fuel naturally blankets the sea beds off Japan and elsewhere that scientists say it could power the world for centuries.

Most nations do not even bother exploring offshore reserves for lack of harvesting technology. But in resource-poor Japan, plucking the deep-sea bounty off its shores is more than science fiction -- it is a national initiative that Tokyo hopes will become reality in 15 years.

"Japan's domestic resources are almost zero, so nonconventional sources are a top priority," said Tetsuo Yonezawa of the methane hydrate research team at the government-backed Japan National Oil Corp.

Japan's push heats up next January, when a drilling ship sets sail for the choppy Pacific Ocean off central Japan to dig 10 to 20 wells in methane hydrate beds along the Nankai Trough, 1,100 meters under water.

By 2011, Japan hopes to determine whether commercial methane hydrate mining is economically feasible and, if so, begin mining four years later.

Methane hydrate is a crystal structure of methane gas surrounded by water molecules, held together by freezing temperature and crushing pressure. Separating the two yields the methane, or common natural gas.

Knowledge of the substance dates to the 1890s. But it never caught on as an energy source because it is found in hard-to-access Arctic permafrost and deep ocean sediments.

Worldwide resources, however, are massive -- at an estimated 25,000 trillion cubic meters, according to current estimates. Deposits around Japan are just a fraction of that but Japan believes it is worth shelling out $120 million next year alone on methane hydrate research to try to boost its energy self-sufficiency.

Japan is not alone in pursuing methane hydrate, but perhaps is the most desperate.

The U.S. Congress has appropriated millions of dollars for research, but projects are focused as much on academic as commercial applications -- in part because methane hydrate on other planets is envisioned as a fuel source for future space travel.

In Russia, the entire Siberian tundra is laced with the frozen fuel. But Russia is so rich in crude oil and traditional natural gas that Moscow spends little time or money trying to perfect thorny methane hydrate mining techniques.

Japan's upcoming tests in the Pacific are aimed at finding a local "sweet spot" of hydrate deposits and learning how to regulate the temperature of the deposit during drilling.

Temperature control is the hardest part -- how to warm vast beds of icy substance and catch the released methane. As soon as the temperature or pressure change, the methane typically gassifies and disappears.

Undersea, the richest methane deposits occur in densely frozen sediment. But there are technical challenges with drilling so deep and keeping the drill bit lubricated.

It is still too soon to tell whether the Japanese project will ever go commercial. And no matter what is achievable, Yonezawa said, it will be impossible to recover 100 percent of the methane hydrate deposits around Japan. But it's worth pursuing..

"There are still a lot of uncertainties," he said. "But the potential is too big to ignore."