New Delhi: The government, for the first time in 2009-10, will embark on a pilot project to produce gas from the estimated 1,894 trillion cubic metres (cu. m) of gas hydrates in Indian waters. India has resources to produce 204,552 million standard cu. m of gas per day (mscmd), around 1,360 times the current demand of 150mscmd.
“Even if we are able to utilize a part of this, our gas requirements will be solved for a long time to come,” said a senior petroleum ministry official. The only problem: The technology to tap gas from gas hydrates is still experimental, and the extraction could come at a big environmental cost.
Gas hydrates are methane molecules trapped in ice. Every block of gas hydrate looks like a chocolate bar, with each slab containing energy-rich methane. Theoretically, each cubic metre slab of hydrate contains about 164 cu. m of methane or natural gas.
Fertilizer and power companies prefer natural gas over other fuels as it costs and pollutes less. The country is currently suffering a gas shortage that is expected to last till 2012, and it doesn’t produce enough oil to feed its growing economy. The ability to extract gas successfully from gas hydrates would not just be a scientific breakthrough, but would ensure India’s energy security.
The National Gas Hydrate Programme was started in 1997 by the petroleum ministry along with Oil and Natural Gas Corp., GAIL (India) Ltd, Directorate General of Hydrocarbons (DGH), Oil India Ltd, National Geophysical Research Institute, National Institute of Oceanography and the department of ocean development.
In 2000, DGH became the technical coordinator of the programme, and through a scientific cooperation programme with the US, acquired core samples of gas hydrates. Scientists, however, are cautious about the prospect of extracting methane from gas hydrates. “I would not be able to tell you India’s commercial potential yet, because a lot more research has to be done,” said M.V. Ramana, a scientist at the National Institute of Oceanography.
One of these expeditions was on the JOIDES Resolution, the only vessel that can drill up to 1,500m below the ocean floor. This expedition detected a huge sediment of gas hydrates off the Krishna-Godavari basin, where several Indian companies have struck gas in recent years. Scientists on the expedition actually managed to dig out cores that indicated a 128m thick layer of gas hydrate at the site.
The technological challenge is to extract gas from solid gas hydrates. India is one of few countries conducting research in this area. (No commercially viable technology exists for the extraction yet.) Such extraction could also come at a huge environmental cost. A kg of methane has almost 23 times the greenhouse warming potential of carbon dioxide. More than half of the methane in the world is believed to be trapped under the ocean floor, close to coastlines, and mining for them could trigger landslides.