By Dr PK Mukherjee
We have thousands of crores to splurge on non-productive entitlements and also to subsidise diesel, kerosene and gas, but none to spend on the research and development necessary to ensure energy security for the country. The latest excitement in the field of energy is extraction of natural gas from gas hydrates. In India, the gas hydrate reserves are tentatively estimated at 1,890 trillion cubic metres, about 1,500 times more than the natural gas present in the known reserves of the country. But we least bother to tap this natural resource to save scarce foreign currency that we spend on import of oil and gas and propel the country into high current account deficit and debt trap....
The extraction of oil and natural gas from the sea beds has been going on the world over for the last many decades. However, over the last few years, a new source of energy, called gas hydrate, has engaged the attention of scientists. India has some of the biggest gas hydrate reserves in the world. But, so far we were short of the technical capabilities for exploitation of this promising new source of energy. However, a global technological breakthrough has recently taken place that can give real impetus to exploration and extraction of gas hydrate in our country.
When methane gas after getting dissolved in water gets frozen due to low temperature and requisite pressure, it turns into ice. This ice buried under the sea sediments is known as gas hydrate and is seen as the future source of energy. The US, Japan and China have started programmes to tap this, but indolent Manmohan Singh government is showing no interest towards this enormous wealth in coastal areas.
Recently, Japan Oil Gas and Metals National Corporation announced that it succeeded in extracting gas from the seabed deposits of gas hydrate. If all goes well, the Japanese Corporation has plans of commercial gas production, may be as early as 2016. Besides Japan, the US and China are also in the race as they have major programmes for exploration and experimental extraction of gas hydrate.
Now, India must also start taking active interest in this area because it has rich reserves of gas hydrate. It would only be prudent to do so as India has to make huge expenditure on the import of oil and gas. India has to spend a whopping 200,000 crores for the import of oil alone. This causes big trade deficit which, in turn, acts as a hurdle to the acceleration of the economic growth of the country.
What is gas hydrate?Gas hydrate is a mixture of methane gas and water that solidifies in the cold and high pressure conditions prevailing in the deep sea beds. The popular name of gas hydrate is ‘fire ice’ because it is a white crystalline solid that burns. Although chiefly found in deep sea beds, gas hydrate is also found in some of the on-shore deposits like in the permafrost of northern Canada and Russia.
Estimates of the global reserves of gas hydrate are sketchy. However, they range from 2,800 trillion to about 8 billion trillion cubic metres of gas. This is several times higher than the global reserves of 440 trillion cubic metres of natural gas. In India, the gas hydrate reserves are tentatively estimated at 1,890 trillion cubic metres. This is about 1,500 times more than the natural gas present in the known reserves of the country.
How can the gas (methane) be extracted from the deposits of gas hydrate? Heating the deposits or lowering the pressure releases gas from the solid gas hydrate. The latter technique was actually used by JOGMEC. One litre of the solid hydrate releases about 165 litres of the gas.
Lacklustre Indian initiativeIn the quest for the gas hydrate deposits in the Indian waters, a Natural Gas Hydrate Programme was started in our country in the year 1996. An Indo-US scientific joint venture in 2006 explored four areas. The areas in the Indian waters explored for gas hydrate deposits were Kerala-Konkan basin in the western coast of Arabian Sea, Krishna-Godavari basin in the Bay of Bengal, Mahanadi basin in the Bay of Bengal and seas off the Andaman Islands. The deposits in the Krishna-Godavari basin turned out to be among the richest and biggest in the world.
The Andaman yielded the thickest-ever deposit, 600 metres below the seabed in the volcanic ash sediments. A fully developed gas hydrate deposit was also found in the Mahanadi basin in the Bay of Bengal. Another significant finding of the 2006 joint exploration was that the methane from most of the gas hydrate deposits was, by and large, produced by microorganisms. However, in the Mahanadi basin and the Andaman, part of the methane appeared to have been produced due to the thermal decomposition processes.
We found in collaboration with the US that deposits in the Krishna-Godavari basin are among the richest and biggest in the world. But then what next?
In the field of gas hydrates much research is in progress in the US, Japan and China. But, there is very little progress in India. The research work being done in this field is also very dismal. We have not gone beyond prospecting the areas where it is located. The Directorate General of Hydrocarbons has long pleaded for the establishment of a National Gas Hydrate R & D Centre, but in vain. This is indeed pathetic. A national R & D Centre seems to be a far cry; we do not till date even have a national policy on gas hydrate.