Methane hydrates: Energy's most dangerous game

by William Pentland Forbes

All the energy America needs for the next 100 years lies under the sea off the coast of South Carolina. One problem: Digging it out could cause a global climate disaster.
Welcome to the final frontier in fossil fuels, the wild card in climate change theories and the dark horse in the scramble to secure access to clean energy. Meet methane hydrates, the world's most promising and perilous energy resource.

Methane is the principal component of natural gas, and massive amounts of it are trapped in reservoirs beneath the sea floor and under a layer of the ice-like substance. The scale of the resource is spectacular. By some estimates, methane hydrates contain more energy content than all other known fossil fuels combined.
Two small areas located roughly 200 miles off the coast of Charleston, SC, contain enough methane to meet the country's gas needs for more than a century. And this is only one of at least two dozen similar reservoirs discovered in US coastal waters since the early 1970s.

Disaster waiting to happen?
The paradox is that while gas can be extracted from methane hydrates, doing so poses potentially catastrophic risks. Methane hydrates are frozen water molecules that trap methane gas molecules in a crystalline, lattice-like structure known as a hydrate. Unlike normal ice, hydrate ice literally burns -- light a match and it goes up in flames. As temperatures rise or pressure rates fall, the hydrate disintegrates and the water releases the gas.
A substantial amount of evidence suggests that weakening the lattice-like structure of gas hydrates has triggered underwater landslides on the continental margin. In other words, the extraction process, if done improperly, could cause sudden disruptions on the ocean floor, reducing ocean pressure rates and releasing methane gas from hydrates.

A mass release of methane into the sea and atmosphere could have catastrophic consequences on the pace of climate change. More than 50 mm years ago, undersea landslides resulted in the release of methane gas from methane hydrate, which contributed to global warming that lasted tens of thousands of years.
"Methane hydrate was a key cause of the global warming that led to one of the largest extinctions in the earth's history," Ryo Matsumoto, a professor at the University of Tokyo who has spent 20 years researching the subject, told in December.

Major resource
But given its potential, the race is on to figure out how to safely exploit this resource. Timothy Collett, a research geologist at the US Geological Survey, has estimated that there could be as much as 317 qn cf of methane gas stored in hydrates in the US.
To put this in perspective, the US Department of Energy estimates that the country has 187 tcf of natural gas reserves. Needless to say, the potential value of gas hydrates as a less-polluting and more secure supply of energy is immense.

Major government research initiatives have been launched in China, India, Germany, Norway, Russia, Taiwan and several other countries. The Japanese government has estimated that producing gas from methane hydrates is commercially viable when oil prices rise above $ 54 a barrel.
In 2003, an international consortium that included Japan, Canada, the US, India and Germany produced natural gas from methane hydrates in the Mackenzie Delta in Canada's Northwest Territories. To date, Japan has made the biggest bet on methane hydrates and appears to be the closest to commercial production.

Since 2000, Japan has drilled nearly three dozen exploratory well holes in the Nankai Trough. Roughly 30 miles off the coast of Honshu Island in the Pacific Ocean, the Nankai Trough holds an estimated 40 tcf of gas hydrates and has received the largest investment and advanced field research of any project in the world.
"We're trying to find the lowest-hanging fruit," says Kelly Rose, a research geologist at the US Department of Energy National Energy Technology Laboratory. "Production is definitely possible if we can keep giving the support needed to figure out how these fields work. In the last six months, things have really started to pick up."

In the US, major federal industry partnerships have been formed in both the Gulf of Mexico and on the North Slope of Alaska. Chevron has led the JIP project in the Gulf of Mexico. BPAX and the US Department of Energy are currently exploring sites for a long-term production facility, which will likely begin in 2009.
Japan and Canada are well into long-term production tests in the Mackenzie Delta that began in 2007. Meanwhile, Japan and Canada are well into long-term production tests in the Mackenzie Delta that began in 2007. In the past two months, the US Department of Energy has completed bilateral agreements with Japan, Korea and India that will increase collaboration on methane hydrates research.

"We think that the future may be sooner than some of us are considering," Robert Hunter, president of ASRC Energy Services, which led the first major fieldstudy in Alaska's Prudhoe Bay with BP Alaska Exploration and the Department of Energy, told. "In parts of the world such as the North Slope, with unique motivation, hydrates may become a very stable source of natural gas within the next five to 10 years."
Ironically, rising sea levels and temperatures appear to be causing methane releases from hydrates with or without drilling. Industry insiders describe the commercialization of gas hydrates as similar to the development of coal bed gas resources. Not very long ago, coal bed methane, which currently accounts for almost 10 % of all US natural gas production, was considered too expensive for commercial production. Technological innovations made coal bed gas a viable fuel.

"In coal bed technology, they kept at it until they found the key that unlocked the door and things started happening, which is likely the way methane hydrates will develop," says Rose.
"The whole goal of our research is to figure out the recipe for how these methane hydrate fields work. It will take different technologies in the future, but getting the recipe is the first big step."