During the fiscal year 2002-03 the estimated total available energy was 18.96 EJ (Domestic 15 EJ, Imported 3.96 EJ). Out of the total, about 71% (13.46 EJ) was the commercial component and 29% (5.49 EJ) non-commercial . During the year 2001, the commercial primary energy consum-ption in the world was about 382 EJ. India’s consumption was merely 3.4% (U.S.A. 24.5%) of world’s commercial energy consumption, while its population stood at nearly 16.6% (U.S.A. 4.6%) of the world’s population. Per capita commercial energy consumption in India stood at nearly 1/5th of the world average and 1/26th of that of the U.S.A . Table 2 gives contribution of various fuels to primary commercial energy and to electrical generation during the year 2002-03.
3.1 Coal and Lignite
India has large reserves of coal and is the third largest coal producing country of the world. As per the estimates of the Geological Survey of India, total gross in situ coal reserves in the country are 245.53 BT (Proven: 93.79, Indicated: 109.50 and Inferred: 42.24). Following the procedure assigning reserves with 90% confidence level to the proven category, 70% to the indicated category and 40% to the inferred category and then applying the criterion of reserve to mineable resource ratio of 4.7:1, the working group on coal & lignite for the 10th five year plan tentatively projected the extractable coal to be only 37.86 BT.
India’s requirements of coking coal are almost entirely fulfilled by imports. Even the non-coking coal is being increasingly imported in order to blend it with Indian coal having high ash content and use in power plants at certain coastal locations due to commercial reasons. During 2001-02 domestic production of coal was about 323 MT, while the net import was at 22.8 MT. In view of the large dependence on coal and its stagnating production, it may be necessary to increase its import. Production of lignite was about 24.8 MT during the same period. The currently known lignite reserves in the country, much less than coal, are estimated to be 34.6 BT (Proven 3.69, Indicated 11.14 and Inferred 19.76). It is relatively a small quantity and cannot make a significant contribution towards long-term energy security.
3.2 Oil and Natural Gas
During the year 2001-02, domestic crude oil production was 32.03 MT as compared to net import of 75.63 MT. In the same year, about 29.7 billion cubic metres of natural gas (NG) was produced domestically. To meet the increasing demand, the government has permitted private sector participation in this field. In November 2002, discovery of a large gas field in Karnataka estimated to contain about 0.2 trillion cubic metre gas was made by a private entrepreneur. There is a high potential for discoveries offshore, particularly in deep waters. Exploration has so far taken place in only about one-quarter of India’s 26 sedimentary basins. It is estimated that these basins may contain as much as 30 BT of hydrocarbon reserves , . India’s recoverable reserves of crude oil and natural gas were till recently considered to be about 600 MT and about 650 billion cubic metres respectively . The Ministry of Petroleum & Natural Gas has set strategic goals for the next two decades (2001-2020) of ‘Doubling Reserve Accretion’ to 12 BT (O+OEG)’ and ‘Improving Recovery Factor to the order of 40%’ . Exploration is a dynamic process and one could expect further growth in reserves in the years to come. Considering that India is one of the least explored countries for oil and gas and the present thrust by GOI in this area, it is assumed that cumulative availability of hydrocarbons up to the year 2052 would be nearly 12 BT of (O+OEG).
Coal Bed Methane (CBM), primarily a methane gas occurring in coal seams, is being harnessed in USA for more than a decade. Resource potential of CBM in our country has been conservatively estimated at 850 billion cubic metres . Exploration and exploitation of CBM is complex and exposure to this technology in India is limited. Efforts are being made to acquire technical know how to harness CBM from on-going mines as well as from virgin coal bearing areas. In near future this new source of energy is expected to come on stream from 8 CBM blocks .
3.3 Hydro Energy
The hydro electric potential in India has been estimated to be 600 billion kWh annually, corresponding to a name-plate capacity of 150 GWe . It is mostly located in the northern and north-eastern regions of the country. As of March 2003, only about 27 GWe has either been developed or is being developed. A vision paper prepared by the Ministry of Power envisions harnessing of entire balance hydro power potential of India by the year 2025-26. It is proposed to add 16 GWe of new capacity in the Tenth Plan and 19.3 GWe in the Eleventh Plan .
3.4 Non-conventional Renewable Energy
The estimated potential of non-conventional renewable energy resources in our country is about 100 GWe. Wind, small Hydro and Biomass Power/ Co-generation have potentials of 45 GWe, 15 GWe and 19.5 GWe respectively ; Solar PV, Solar Thermal and Waste-to-Energy being the other important components. All these resources will be increasingly used in future especially in remote areas. The medium term goal is to ensure that 10% of the installed capacity to be added by the year 2012, i.e. about 10 GWe, comes from renewable sources. Good progress has been made in the field of wind power and installed capacity additions in the recent years have been quite impressive. However, the wind mills have, so far, reported very poor capacity factors, (14% for wind power during the year 2002-03).
3.5 Nuclear Energy
As in case of coal, uranium reserves are also given certain categorisation. These are Reasonable Assured Resources (RAR), Estimated Additional Resources-I (EAR-I), Estimated Additional Res-ources-II (EAR-II) and Speculative Resources (SR). Uranium reserves in India pertaining to categories RAR, EAR-I and EAR-II are estimated to be about 95,000 tonnes of metal. Speculative reserves are over and above this quantity and with further exploration, could become available for nuclear power programme. After accounting for various losses including mining (15%), milling (20%) and fabrication (5%), the net uranium available for power generation is about 61,000 tonnes. Thorium reserves are present in a much larger quantity. Total estimated reserves of monazite in India are about 8 million tonnes (containing about 0.63 million tonnes of thorium metal) occurring in beach and river sands in association with other heavy minerals. Out of nearly 100 deposits of the heavy minerals, at present only 17 deposits containing about ~4 million tonnes of monazite have been identified as exploitable. Mineable reserves are ~70% of identified exploitable resources. Therefore, about 2,25,000 tonnes of thorium metal is available for nuclear power programme.
The present indigenous nuclear power plants are of Pressurized Heavy Water Reactor (PHWR) type, having heavy water as moderator and coolant, and working on the once-through-cycle of natural uranium fuel. Based on such reactors nearly 330 GWe-yr of electricity can be produced from domestic uranium resource. This is equivalent to about 10 GWe installed capacity of PHWRs running at a life-time capacity factor of 80% for 40 years. This uranium on multiple recycling through the route of Fast Breeder Reactors (FBR) has the potential to provide about 42,200 GWe-yr assuming utilisation of 60% of heavy metal, percentage utilisation being an indicative number. Actual value will be have the potential of about 150,000 GWe-yr, which can satisfy our energy needs for a long time.
A three-stage nuclear power programme has been chalked out in the Department of Atomic Energy to systematically exploit all these resources. It is planned to install a nuclear power capacity of about 20 GWe by the year 2020. The second stage of the nuclear power programme envisages building a chain of fast breeder reactors multiplying fissile material inventory along with power production. Approval of the Government for the construction of the first 500 MWe Prototype Fast Breeder Reactor (PFBR) was obtained in September 2003 and it is scheduled for completion in the year 2011. It is envisaged that four more such units will be constructed by the year 2020 as a part of the programme to set up about 20 GWe by the year 2020. Subsequently FBRs will be the mainstay of the nuclear power programme in India. The third stage consists of exploiting country’s vast resources of thorium through the route of fast or thermal critical reactors or the accelerator driven sub-critical reactors (ADS) . A 300 MWe Advan-ced Heavy Water Reactor (AHWR), designed to draw about two-third power from thorium fuel, is under development and will provide experience in all aspects of technologies related to thorium fuel cycle. A beginning is being made towards developing an accelerator needed for ADS.
3.6 New Fuel Resources and Technologies
With enhanced exploration and mining, in tune with the trend so far, it is likely that new deposits of coal and hydrocarbons will be discovered, thereby increasing our resource base in future. New technologies such as in situ coal gasification will make more efficient use of the present resources and will enable the country to tap resources presently considered uneconomical.
A recent article in Nature gives account of hydrocarbons and how the energy-returned-on-energy-invested (EROI) has tended to decline over time for all energy resources. For example, the EROI of oil in the US has decreased from a value of at least determined as one proceeds with the progra-mme and gets some experience. Issues involved are fuel burn-up, extent of multiple recycling possible, cycle losses during reprocessing and re-fabrication, and out-of-pile period consisting of transportation, storage, reprocessing, re-fabrication etc. FBR generation potential indicated above is equivalent to an installed capacity of about 530 GWe operating for 100 years at a life-time capacity factor of 80%. The thorium reserves, on multiple recycling through appropriate reactor systems, 100 to 1 for oil discoveries in 1930s to about 17 to 1 today for oil and gas extraction. The paper also says that the alternate liquid fuels such as ethanol from corn have a very low EROI. An EROI of much greater than 1 to 1 is needed to run a society. For a country like India having a high density of population, non-conventional renewable energy resources would continue to be important, but low EROI and competing pressures on the use of land would not permit them to contribute a significant share to the total energy mix.
US Department of Energy has funded eight projects under the Clean Coal Initiative and has also ann-ounced plan to develop a pollution free coal fired power plant (Code named ‘FutureGen’) of the future . Similar proactive efforts are needed in India in the areas of coal mining as well as coal based power plant technologies.
Many countries have interest in exploiting the gas hydrates. Gas hydrates or methane hydrates are ice-like solids in which water molecules form cages around molecules of methane, the chief component of natural gas. Reserves of hydrates may offer more energy than coal . However, this resource needs to be precisely evaluated. In India also these resources are being identified. Estimates of this rather newly identified energy resource in India vary by orders of magnitude. According to a press report , various agencies in India have mapped out 6150 trillion cubic meters of gas hydrates along the southern coastline of the Indian peninsula. However, the technology of gas production from hydrates is yet to be commercially proven. The Department of Science and Technology (DST) is pursuing a proposal to develop technologies for exploiting gas hydrates in collaboration with Russian Federation.
Fusion is another attractive long-term energy option and R&D on fusion is being done worldwide including in India at the Institute for Plasma Research, Gandhinagar, Gujarat. Fusion based reactor systems may become a reality by middle of the century.
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