Japan Is Unlocking The Potential Of ‘Flammable Ice’
In March, the Japanese government announced that it had successfully produced methane from hydrates in sediments under the Pacific Ocean. It was the world’s first hydrate production test in deep water.
The road to Japan’s energy future runs through a cluster of low buildings in this city, the largest on the northern island of Hokkaido.
Hydrate-containing sediments are found in large amounts around the world, both under the sea and to a lesser extent in permafrost. If they can be tapped safely and economically, they could be an abundant source of fuel, especially for countries like Japan that have few energy reserves of their own.
The Japanese researchers’ work has already borne fruit: in March, the government announced that it had successfully produced methane from hydrates in sediments under the Pacific Ocean. The effort, conducted from a drilling ship in the Nankai Trough about 100 miles east of Osaka, was the world’s first hydrate production test in deep water.
But scientists say there is still much that is unknown about the unusual compounds, sometimes referred to as “flammable ice,” and that the commercial production of gas from them is still far-off. “We need to know more about the physical properties of hydrates themselves, and of the sediments as well,” said Hideo Narita, the director of the research laboratory, part of the National Institute of Advanced Industrial Science and Technology, which is financed largely by the government.
Further research, here and at labs around the world, will help scientists better understand the environmental impact of hydrate production, including the possible release of methane, a potent greenhouse gas, into the sea or atmosphere. There is also the potential for subsea landforms to become unstable when hydrates are removed.
Timothy S. Collett, a research geologist with the United States Geological Survey, said that despite all the talk about their potential as an energy resource, “hydrates are largely still a scientific issue.”
The research poses special challenges because hydrates form under high pressure, caused by the weight of all the seawater or rock above them, and that pressure must be maintained when the sediment cores are analyzed. If it is not, the hydrates within quickly dissociate into water and gas, and the sediments “look like chocolate mousse,” said Carlos Santamarina, a professor at Georgia Tech.