by Michael Fitzpatrick, Guardian
In a bid to shore up its precarious energy security, Japan is to start commercial test drilling for controversial frozen methane gas along its coast next year.
The gas is methane hydrate, a sherbet-like substance consisting of methane trapped in water ice—sometimes called "fire ice" or MH—that is locked deep underwater or under permafrost by the cold and under pressure 23 times that of normal atmosphere.
A consortium led by the Japanese government and the Japan Oil, Gas and Metals National Corporation (Jogmec) will be sinking several wells off the southeastern coast of Japan to assess the commercial viability of extracting gas from frozen methane deep beneath local waters. Surveys suggest Japan has enough methane hydrate for 100 years at the current rate of usage.
Lying hundreds of meters below the sea and deeper still below sediments, fire ice is exceedingly difficult to extract. Japan is claiming successful tests using a method that gently depressurizes the frozen gas.
Tokyo plans to start commercial output of methane hydrates by 2018. At present, Japan imports nearly all its gas—about 58.6 million tons of liquified gas annually—and is heavily dependent on oil imports. In a desperate attempt to secure more oil, for example, Japan recently did a deal with the United Arab Emirates. In exchange for using Japan as a base for Asian oil trading, Japan now has priority to purchase rights to up to 4 million barrels of immediately accessible crude.
Lucia van Geuns, an energy analyst at the international energy program of the Clingendael Institute, said: "Methane hydrates could make Japan energy independent. Japan put a lot of R&D into this project because of course the less energy it imports the better. Whether they can commercialize methane hydrates remains to be seen.
"If it does succeed, and that’s very much a long shot, it will have a huge impact—equivalent to the use of gas shales in the U.S."
Japan’s trade ministry, which is behind the scheme, has requested a budget of $105.6 million (¥8.9 billion) for the drilling to start next spring. The huge budget reflects the difficulties of drilling deep offshore. In Japan, hydrates in the Sea of Kumano are found about 30 kilometers offshore in about 100 meters of water and at a depth below the seabed of 200 meters, making it difficult to mine the unstable hydrates.
Concerns had been raised that digging for frozen methane would destabilize the methane beds, which contain enough gas worldwide to snuff out most complex life on earth. Methane itself is a greenhouse gas which is 21 times as damaging as carbon dioxide, and any leakage from wells could be an environmental problem.
Professor Gerald Dickens, of Rice University in Texas, a leading researcher into methane hydrates, thinks accidental releases can be avoided."The only potential issue in regards to drilling would be if there is greatly over-pressured gas immediately beneath the gas hydrate. However, there is growing belief and rationale to suggest that this cannot occur in nature. So, as far as drilling there should be no issue."
Environmentalists, however, are concerned about the burning of more earth-locked hydrocarbons. Methane may be a cleaner-burning fossil fuel than coal or oil but will still release many tons of CO2. Jogmec acknowledges the problems, admitting mining of methane ice could lead to landslides and the devastation of marine life in the mining areas. "There are many other technological problems to overcome," says the Jogmec website. "Not least that when you drill you create heat, which turns the frozen methane into gas, which could then leak uncontrollably through the sea to our atmosphere."
The U.S., China, Canada and South Korea are among other countries seeking to develop commercially viable extraction technology, and each is now exploring the mining of methane hydrates from their own sea beds.
"Some commercial production of methane from methane hydrate could be achieved in the United States before 2025," says a U.S. government report on the subject.
(Republished with permission)