In view of the ever-increasing demand for hydrocarbons and near stagnant domestic production of crude oil, the government is on the lookout for alternative sources of hydrocarbons. Coal bed methane (CBM) is one such alternative that has the potential to meet much of India's energy requirement.
According to a survey by Reliance Gas, about 20,000 sq. km of area has prospect for CBM with estimated 'in place' resource of about 2,000 billion cubic metres. Recoverable reserves of about 800 billion cubic metres and gas production potential of about 105 million metre cum per day over 20 years have been estimated. This is 1.5 times the current natural gas production that can generate 19,000 mw of electricity.
The government has taken up a demonstration project (costing Rs 76.85 crore), namely Coal Bed Methane Recovery and Commercial Utilisation in collaboration with the United Nations Development Programme and Global Environment Facility at Moonidih and Sudamdih mines of Bharat Coking Coal Ltd in Jharia Coalfields, Dhanbad. The Central Mine Planning and Design Institute Ltd is the main local implementing agency on behalf of the Government of India. Bharat Coking Coal Ltd is the co-implementing agency. The project is under implementation and use of coalmine gas to be recovered as a consequence of this project is one of the objectives of this project.
The government formulated a Coal Bed Methane (CBM) Policy in 1997 for exploration and production of CBM from coal/lignite bearing areas. Under this policy the government identified 16 blocks located in West Bengal, Jharkhand, Madhya Pradesh, Maharashtra, Chhattisgarh, Rajasthan and Gujarat for E&P of CBM. All these blocks have been allotted to various companies, both in public and private sector. In private sector, Reliance Industries, Essar Oil and Great Eastern Energy Corporation have won the contracts.
As per the CBM policy, a contractor gets a maximum of 13 years (8 years for exploration and 5 years for development) to explore and develop a CBM block from the effective date. However, there is a provision that the number of years can be reduced if the contractor desires to do so. Many companies have started working on the blocks awarded. ONGC is expected to award the exploratory and development drilling contracts for CBM this month. Earlier, the company was to start drilling last November. ONGC had held prolonged negotiations and pre-bid exercises with technology companies. But, the company could not award turnkey contracts for exploration, development and production of CBM due to lukewarm response from the tech companies.
Now development drilling is expected to begin with the Jharia block, where ONGC has identified sufficient reserves during its decades-long exploratory drilling. The block was held through a 90:10 joint venture with Coal India Ltd. The company has already commenced exploratory drilling
at Bokaro block, using its own rig. The block is held through an 80:20 joint venture with
Indian Oil.
Essar Oil's CBM division has pioneered a project in Mehsana, Gujarat, using innovative technology and extensive studies to establish the presence of methane gas deep in the coal reservoirs. Essar has already drilled three wells to a depth of 1,450 metres and is producing the gas experimentally. Essar claims to be the only company in India with the knowhow and to have carried out such a project. If everything goes as per plan Essar Oil may become the first company in India to exploit CBM commercially. This is likely to happen in 2006-07.
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Global hunt for CBM |
In the process of coal formation, anaerobic conditions led to generation and trapping of methane in this coal seams. The pressure exerted by naturally formed water keeps the methane "absorbed" on internal surfaces of coal. Thus, coal bed gas is in mono-molecular state and not as free gas, as in natural oil/gas fields. Therefore, all coalfields of the world have coal bed methane, the only difference being the quantity of gas in individual coal seams.
USA is the pioneer in exploiting this source of energy and is the largest producer of methane gas from coal bed and nearly 8 per cent of the gas produced in that country comes from CBM. China is emerging as a major player and Australia is on the threshold of commercial production of coal bed methane.
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