Now comes the hard part.
In a world first, Japan announced March 12 that it had succeeded in producing methane gas from deposits of hydrates beneath the ocean floor. Making it commercially practical is another challenge entirely, say American scientists who have worked with the Japanese researchers.
“It’s still very much a science topic. It’s early days in understanding this resource,” Timothy Collett, a research scientist in the energy resources program of the U.S. Geological Survey in Denver, said in an interview Wednesday.
The good news is that methane hydrates—known in Japan as ignik sikumi, or “fire ice”—are incredibly abundant. The hydrates are methane molecules trapped in a cage of frozen water molecules, like an energy-rich sherbet. They’re found in places with low temperatures and high pressures, such as the Arctic tundra and the seafloor. The USGS says that worldwide, the methane trapped in hydrates is probably at least 100,000 trillion cubic feet, or more than 4,000 times all the natural gas consumed in the U.S. in 2010.
But getting the methane out of the hydrates is hard. Much, possibly most, are in mud or other geological formations that are nonporous, so the gas can’t be sucked out of them. The ideal formation is sandstone, which is porous like a sponge; the Japanese production test is in a sandstone deposit off the Japanese coast.
According to Ray Boswell, who heads the hydrates program at the Department of Energy’s National Energy Technology Laboratory, the Japanese press has reported that hydrates could become a resource option for Japan by 2018 or so. “I see no technological barriers that would stand in their way of accomplishing this,” he said in an e-mail.
In the development of hydrates, U.S. scientists see the Japanese as collaborators, not rivals. Japan has put a major emphasis on hydrates research because it lacks conventional oil and gas deposits and pays much more than Americans do for natural gas. South Korea, China, and India are also active. In the U.S., where natural gas is abundant, the need to develop hydrates is considered less urgent.
The U.S. Department of Energy and ConocoPhillips (COP) have collaborated with the Japan Oil, Gas and Metals National Corp. on studying methane hydrates on Alaska’s North Slope. In the winter of 2011-12, the team produced small amounts of methane in tests. Japan’s offshore production is different, Collett says, “because it is the first time anyone has tested production in the complexity of a marine environment.”
