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www.sea-technology.com April 2015 / st 19 F art jokes aside, methane isn't all that exciting. But for energy-hungry nations such as Japan and India, methane could be the key element to developing national energy in- dependence. Methane in the form of methane hydrate, a crystalline form of natural gas found at the bottom of oceans and in the Arctic permafrost, will within the next 20 years reshape the global geopolitical landscape of energy. At room temperature, a solid chunk of methane hydrate can be lit with a single match, producing intense heat. Colloquially known as "fre ice," there is an estimated 20 quadrillion (20 x 10 15 ) cubic meters of the substance lying several hundred meters below sea level, scattered along continental slopes and in the Arctic permafrost. According to the U.S. Geological Sur- vey, the enormous worldwide reservoirs of methane hydrate potentially contain more energy than all previously discov- ered conventional oil and gas reserves combined. As mind-blowing as the numbers seem, until recently methane hydrate had never been seriously considered as a viable source of energy. According to oil and gas industry professionals, methane hydrates are considered a nuisance as the substance clogs up natural gas pipelines, disrupting fow. Since the 1940s, natural gas pipeline operators have spent considerable portions of their operating budgets de- vising ways to get rid of chunks of methane hydrate that form in areas where the pipeline has been exposed to cold temperatures. Methane may be the butt of any number of jokes, but as the smallest and simplest molecule in the Alkane family, this saturated hydrocarbon is found in nearly every crude oil and natural gas. In fact, according to Canada's largest natural gas distributor, Enbridge (Calgary, Canada), natural gas is 95 percent methane. Why Does Methane Get a Bad Rap? At standard pressure and temperature, methane is an odorless and colorless gas that contains only two elements— carbon and hydrogen—and is essentially insoluble in water. Yet as scientists investigating pipeline blockages discovered, when CH 4 and water combine at cold temperatures (around 25°C) and pressures (30 to 50 bar) found at 300 to 500 meters ocean depth, methane gas can be trapped in ice- like structures called methane clathrates. At the molecular level, these methane clathrates, or gas hydrates, consist of meth- ane molecules surrounded by tight cages of interlocking water molecules. The hydrates contain large amounts of gas in a rela- tively small area; for example, 1 cubic meter of hydrate can hold around 164 cubic meters of methane and 0.8 cubic meters of water. As a Fuel Source, Methane Is No Longer a Laughing Matter This is not to say that extracting methane gas from meth- ane hydrates is a walk in the park. There are a multitude of technical challenges, and until recently it has generally been considered that other sources of fossil fuels—conventional oil and gas and more recently shale oil and gas—have been easier and cheaper to access. But that may be changing. In 1998, the Mallik Gas Hydrate Production Research Well became the frst site dedicated to drilling gas hydrates bearing deposits. Located in the pristine beauty of the Ca- nadian Beaufort Sea, the Mallik Gas Hydrate site has been the site of extensive gas hydrate research and development studies, including a 2008 proof of concept that showed that, with some modifcations for the unique properties of gas hydrates, production from a gas hydrate reservoir can be achieved using the same completion and production meth- ods used in conventional oil and gas industries. Since the proof of concept, Japan and India have taken the lead in methane hydrate research, with the goal of fnding extract- able deposits and developing ways to extract methane eco- nomically. A big breakthrough came in March 2013, when Tokyo- based Japan Oil, Gas, and National Metals Corp. (JOGMEC) announced that they had successfully extracted fuel from a The Arctic as the Next Global Energy Powerhouse Methane Hydrates May Hold the Key to Energy Independence By Kell Sloan The Mini-Pro CH 4 sensor.