Gas, Natural

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Gas, Natural mixture of flammable gases found in the earth's crust (often in association with petroleum), now one of the world's three main fossil fuels (with coal and oil). In other words, hydrocarbons that exist as gas or vapour at ordinary pressures and temperatures. Methane is the most important, but ethane, propane and others may be present. Common impurities include nitrogen, carbon dioxide and hydrogen sulphide. It may occur alone or associated with oil. Being a delta having a porous and permeable hydrocarbon-bearing sand structure and unique conditions for trap, Bangladesh has always been considered a natural gas rich country.

It is largely available in the eastern part of the country extending from greater Sylhet down to greater Comilla, Noakhali and Chittagong. It has also been discovered offshore in the bay of bengal.

Natural gas plays an important role in the country's economy. It is an environment friendly fuel, which undergoes clean and odourless combustion. It is widely used as fuel for domestic (cooking and heating), industrial (metallurgical, ceramic, glass, bread and biscuits, power stations, cement works, factory process steam boilers, etc) and agricultural (drying, heating, steam boilers) use. liquefied petroleum gas (LPG), Liquefied Natural Gas (LNG), compressed natural gas (CNG) are obtained from natural gas and are used as fuels in domestic, industrial and agricultural applications. In chemical industries natural gas is used as feedstock for the manufacture of fertilisers, plastics, resins, rubbers, and various chemicals such as carbon black, detergents, ammonia, nitric acid, weed killers, etc. [M Ehsanullah]

History of exploration Hydrocarbon exploration in this region commenced towards the end of the nineteenth century. In 1866 four wells were drilled near Jaipur (southwest of Digboi, Assam). The Assam Railway and Trading Company constructed the first railway in the eastern part of the Indian subcontinent in the late nineteenth century. The same company started the exploration of hydrocarbons and drilling works in 1883 in the territory of Assam. Later, the Assam Oil Company was formed, and it expanded its exploration activities for petroleum products. The Burma Oil Company, the successor of the Assam Oil Company, started its petroleum exploration activities in 1911 and included the surma basin and Chittagong area in its exploration programme.

During 1908-1914 the Indo-Burma Petroleum Company drilled a few wells in the Sitakunda anticline. Since 1914 62 wells have been drilled within the territory of present-day Bangladesh. Various national and international companies carried out exploration drilling work in the potential areas of the country. Extensive exploration work so far has secured the discovery of 23 gasfields and one oil well. In the early days of exploration (1910-1933), drilling for oil and gas was mainly concentrated near the seeps in the fold belt. At this stage shallow wells ranging from 763 to about 1,050 meters were drilled. With the evolution of technology drilling reached deeper horizons, with a better success ratio. The first gasfield discovered in Bangladesh territory was in 1955 by the Burma Oil Company. During the sixties and seventies, several gasfields were discovered. Petroleum exploration drilling in Bangladesh territory has an attractive average 3:1 success ratio, which is one of the highest in the world. During 1910-1933 six wells were drilled without any commercial discovery. After the Second World War, during 1951-1970, a total of 22 wells were drilled, and eight gasfields discovered. In the third phase of exploration, during 1972-1992, a total of 24 wells were drilled and nine gasfields and one oilfield discovered. During 1993-2000 10 holes were drilled and five more gasfields were discovered in the country.

In 1959 the Chhatak Cement Factory started using natural gas from Chhatak gasfield; this was the beginning of the industrial use of gas in the country. In the same region, from 1961, the Fenchuganj Fertiliser Factory started using natural gas from the Sylhet gasfield and from 1968, the Siddirganj Power Plant started power generation with gas from the Titas gasfield. They were the major gas users in the country in the early days. In 1968, the eminent author late shawkat osman's residence at Dhanmondi in Dhaka became the first domestic consumer of piped natural gas. In 1960 the average demand and supply of natural gas was 0.28 million cu m/day. It has significantly increased and now stands at about 28 million cu m/day (on March 7, 2000 gas production in the country reached 29.68 million cu m/day) with an installed production capacity of 37.96 million cu m/day from 42 producing wells. [Badrul Imam and Mushfiqur Rahman]

Gas prone Bangladesh is a proven gas prone country in the world. It is mainly found in the rocks of Bhuban and Boka Bil formations. These Miocene shales, particularly the Middle and Lower Bhuban, have a total organic carbon content of up to 0.9%, and are gas prone and classified as marginal source rocks. The gas prone marginal source rocks of the Miocene Bhuban and Boka Bil formations came into the gas maturation level only during the last three to four million years and especially with respect to the deeper basin parts and the Lower Bhuban Formation. Gas generated from these sediments has been trapped almost entirely by the anticlines, which by that time had developed in the Surma Basin. Some geologists believe that the argillaceous rocks of the Bhuban Formation contain little organic material to be a good source rock. They further believe that the underlying organic rich argillaceous rocks of the Oligocene Barail Formation have actually generated natural gas and after migrating for a few kilometres updip it finally accumulated in the sandstone reservoirs of the Bhuban and Boka Bil formations. [Sifatul Quader Chowdhury]

Gasfield By 2001, a total of 22 natural gasfields have been discovered in Bangladesh. The total gas initially in place (GIIP) in these 22 fields is about 26 Tcf, of which about 16 Tcf is considered recoverable. By the end of 2000, a total of about 3.9 Tcf of gas has been produced leaving a reserve of about 12.1 Tcf. Out of the 22 fields, two are offshore in the Bay of Bengal and the rest are located in the eastern onshore areas. The gas occurs in Miocene (5 to 24 million years before present)-Pliocene (2 to 5 million years before present) sandstone reservoirs at depths of about 1,000 to 3,500m below the surface.

Gasfield

Natural gas from Bangladesh is very pure, with about 95% to 99% methane and almost no sulphur. The average compositions are 97.33% methane, 1.72-% ethane, 0.35% propane and 0.19% higher hydrocarbons. Gas in most of the fields is dry, but in a few fields it is wet, with considerable amounts of condensate, eg at Beanibazar (16 bbl/mmcfg), Jalalabad (15 bbl/mmcfg), and Kailashtila (13 bbl/mmcfg). The total condensate reserve in the country is estimated at about 65 million barrels.

Geological evidence suggests that in addition to the hydrocarbon gas already discovered, the prospect of further gas discovery in the country is bright. Natural gas is playing a vital role in the economic development of the country.

Table 1  Exploration onshore wells in Bangladesh.

Well name Year of Drilling Operator Total depth (m) Formation at total depth Tectonic setting Status
Sitakund-1 1910 IPPC 760 Bhuban Fold Belt Dry hole
Sitakund-2 1910/14 IPPC - Bhuban Fold Belt Dry hole
Sitakund-3a 1910/14 IPPC - Bhuban Fold Belt Dry hole
Sitakund-4 1914 Burmah Oil 1024 Bhuban Fold Belt Dry hole
Patharia-1 1923 Burmah Oil 875 Bhuban Fold Belt Dry hole
Patharia-2 1933 Burmah Oil 1047 Bhuban Fold Belt Dry hole
Patharia-3 1951 PPL 1649 Bhuban Fold Belt Dry hole
Patharia-4 1953 PPL 830 Bhuban Fold Belt Dry hole
Patiya-1 1953 PPL 3102 Bhuban Fold Belt Dry hole
Sylhet-1 1955 PPL 2379 Bhuban Fold Belt Gasflow,blowout
Sylhet-2 1956 PPL 2819 Bhuban Fold Belt Gas discovery
Lalmai-1 1958 PPL 2993 Bhuban Fold Belt Dry hole
Chattak-1 1959 PPL 2135 Bhuban Fold Belt Gas discovery
Kutchma-1 1959 Stanvac 2875 Gondwana Stable shelf Dry hole, Coal
Bogra-1 1960 Stanvac 2187 Basement Stable shelf Dry hole
Fenchuganj-1 1960 PPL 2438 Bhuban Fold Belt Dry hole
Rashidpur-1 1960 Shell Oil 3860 Bhuban Fold Belt Gas discovery
Hazipur-1 1960 Stanvac 3816 Barail Hinge zone Dry Hole
Lalmai-2 1960 PPL 4117 Bhuban Fold Belt Dry Hole
Kailastila-1 1962 Shell Oil 4139 Bhuban Fold Belt Gas discovery
Titas-1 1962 Shell Oil 3758 Barail Fold Belt Gas discovery
Habiganj-1 1963 Shell Oil 3508 Bhuban Fold Belt Gas discovery
Jaldi-1 1965 OGDC 2300 Bhuban Fold Belt Dry hole
Jaldi-2 1966 OGDC 3360 Bhuban Fold Belt Dry hole
Semutang-1 1969 OGDC 4088 Bhuban Fold Belt Gas discovery
Bakhrabad-1 1969 Shell Oil 2838 Bhuban Fold Belt Gas discovery
Jaldi-3 1970 OGDC 4500 Bhuban Fold Belt Dry hole
Muladi-1 1976 Petrobangla 4732 Bhuban Foredeep Dry hole
Begumganj-1 1977 Petrobangla 3655 Bhuban Fold Belt Gas discovery
Muladi-2 1981 Petrobangla 4556 Bhuban Foredeep Dry hole
Singra-1 1981 Petrobangla 4100 Gondwana Stable shelf Dry hole
Beanibazar-1 1981 Petrobangla 4109 Bhuban Fold Belt Gas discovery
Feni-1 1981 Petrobangla 3200 Bhuban Fold Belt Gas discovery
Kamta-1 1982 Petrobangla 3614 Bhuban Foredeep Gas discovery
Atgram-1 1982 Petrobangla 2518 Barail Fold Belt Dry hole
Fenchuganj-2 1988 Petrobangla 4977 Bhuban Fold Belt Gas discovery
Salbanhat-A 1988 Shell Oil 2518 Basement Sub-Himalayan Foredeep Dry Hole
Sitakund-5 1988 Petrobangla 4005 Bhuban Fold Belt Dry Hole
Sitapahar-1 1988 Shell Oil 1560 Bhuban Fold Belt Dry Hole
Jalalabad-1 1989 Scimitar 2626 Bhuban Fold Belt Gas discovery
Bogra-2 1989 Petrobangla 2100 Cherra/Tura Stable Shelf Dry hole
Meghna-1 1990 Petrobangla 3069 Bhuban Fold Belt Gas discovery
Narsinghdi-1 1990 Petrobangla 3450 Bhuban Fold Belt Gas discovery
Patharia-5 1992 Petrobangla 3438 Bhuban Fold Belt Dry hole
Shahbazpur-1 1995 Petrobangla 3342 Bhuban Foredeep Gas discovery
Shaldanadi-1 1996 Petrobangla 2511 Bhuban Fold Belt Gas discovery
Maulvi Bazar-1 1997 Occidental 800 Bokabil Fold Belt Gas flow, blowout
Maulvi Bazar-2 1997 Occidental 3735 Bhuban Fold Belt Gas discovery
Halda-1 1997 Cairn Energy 4519 Bhuban Fold Belt Dry hole
Bibiyana-1 1998 Occidental 4205 Bhuban Fold Belt Gas discovery
Kapna-1 1998 Unocal 3149 Bhuban Fold Belt Dry hole
Ratna-1 1999 Unocal 3835 Bhuban Fold Belt Dry hole

Source  Petrobangla, unpublished Government and oil company reports.

The discovered gasfields are at Sylhet, Chhatak, Titas, Rashidpur, Kailastila, Habiganj, Bakhrabad, Semutang, Kutubdia, Begumganj, Kamta, Feni, Beanibazar, Fenchuganj, Jalalabad, Narsingdi, Meghna, Shahbazpur, Saldanadi, Sangu, Bibiyana and Maulvi Bazar. Most of the gasfields are located in and around the frontal fold belt of the Indo-Burman Ranges in the eastern part of the country.

Table 2  Exploration offshore wells in Bangladesh

Well name Year of Drilling Operator Totaldepth (m) Formation at total depth Tectonic setting Status
Cox's Bazar 1969 Shell Oil 3698 Bhuban eq. Fold Belt Dry hole
BODC-1 1976 BODC 4598 Bhuban eq. Foredeep Dry hole
Bina-1 1976 INA 4095 Bhuban eq. Foredeep Dry hole
ARCO-1 1976 ARCO 3903 Bhuban eq. Foredeep Dry hole
BODC-2 1976 BODC 4436 Bhuban eq. Foredeep Dry hole
Kutubdia-1 1977 Union 3508 Bhuban eq. Foredeep Gas discovery
Bina-2 1977 INA 4294 Bhuban eq. Foredeep Dry hole
BODC-3 1978 BODC 4488 Bhuban eq. Foredeep Dry hole
Sangu-1 1996 Cairn Energy 3500 Bhuban eq. Fold Belt Gas discovery
Sonadia-1 1997 Cairn Energy 4028 Bhuban eq. Foredeep Dry hole
Reju-1 1999 Oakland 4450 Bhuban eq. Foredeep Dry hole
Sandwip-1 2000 Shell Oil NA Bhuban eq. Fold Belt Dry hole

Source  Petrobangla, unpublished Government and oil company reports.

Gas is accumulated in the anticlinal traps. The reservoir quality, eg porosity and permeabilty of the gas reservoirs, is from generally good to excellent. Many of the fields have multiple sand reservoirs, with some having as much as 12 gas sand zones. Results of different analyses of gases from Bangladesh fields indicate that natural gas is mostly derived from terrestrial organic matter and were generated within the 'oil window'. The source rocks of the gas are considered to be the Oligocene (24 to 36 million years before present) shale belonging to the Barail Group stratigraphic unit. The gas is supposed to have migrated medium to long distances from Oligocene shale source rocks to Miocene sandstone reservoir rocks via fault conduits.

The current major gas producing fields are Titas, Kailastila, Habiganj, Rashidpur, Jalalabad and Sangu. Brief descriptions of some individual gasfields are given below:

The Sylhet gasfield is located about 20 km northeast of Sylhet town. It was discovered in 1955 by Pakistan Petroleum Limited. Seven wells were drilled, out of which Sylhet-1 was blown out, Sylhet-3 and 6 are producing gas and Sylhet-7 is the only well where oil was discovered. Crude oil was produced from Sylhet 7 well till 1992 at a modest rate of less than 100 to 300 bbl per day.

The Chhatak gasfield was discovered in January 1959 in Sunamganj district by Pakistan Petroleum Ltd. It was drilled up to 2,133m depth. Production in the field was suspeneded since 1985 because of excessive water flow.

The Titas gasfield is located in Brahmanbaria district and was discovered by Pakistan Shell Oil Company in 1962. This is one of the largest gasfields in Bangladesh and the most important gas producer to date. Till 2000 a total of 14 wells were drilled in the field. This field has a dome-like structure covering an area 16 km by 4 km. Most of the gas producing sands are from depths ranging from 2,616 to 3,124m. The Titas field has 4.13 Tcf of gas initially in place (GIIP) of which 2.1 Tcf is considered recoverable reserve. Till the end of 2000, a total of 1.72 Tcf of the gas or about 75% of the recoverable reserve has been extracted.

The Rashidpur gasfield was discovered in Maulvi Bazar district in 1960. Four wells have been drilled in this structure. It has a GIIP of 2.24 Tcf of which 1.30 Tcf is considered recoverable. The structure is a narrow asymmetrical anticline with about 40 km length and 5 km width. This gasfield has been productive since 1983.

The Kailastila gasfield, located in Sylhet district, was discovered by Pakistan Shell Oil Company in 1962. It is one of the largest gasfields in Bangladesh. It has GIIP of 3.65 Tcf with a recoverable reserve of 2.52 Tcf of gas. The Kailashtila field produces a high amount of condensate along with the gas. Kailashtila has been producing gas since 1983. Some non-commercial oil zones have been discovered at a deeper level in this field.

The Habiganj gasfield is another large field discovered in 1963. The field has a closure 11 km long and 4.5 km wide. It is known for excellent quality reservoirs with up to 30% porosity and several darcy permeability. This is one of the major gas producers at the present time. Till date 10 wells have been drilled in this structure.

The Bakhrabad gasfield is located in Comilla district, was discovered by Shell Oil Company in 1969. The field started production in 1984 and reached its peak of 190 million cubic feet of gas per day in 1993. Since then there has been a quick decline of pressure and production rate in the field. By the end of 2000, the field was producing only 35 million cubic feet of gas per day. It is believed the field will be depleted soon.

The Semutang gasfield, located in Khagrachhari district, is the only field in the chittagong hill tracts. It was discovered by the National Oil Company OGDC of Pakistan in 1969. They drilled four wells but wells 3 and 4 were found dry. This field is not in production.

The Kutubdia gasfield, discovered in Bay of Bengal by the Union Oil Company of USA in 1976, is about 92 km southwest of Chittagong Port. Being small in size, no plan has yet been drawn for the development of this offshore field.

The Begumganj gasfield, located in Noakhali district, was discovered in 1977 by petrobangla, and being small has not yet been developed. Of the two wells drilled one was found dry.

The Kamta gasfield located not far from Dhaka city is in Gazipur district and was discovered by Petrobangla in 1981. Production in this small field was suspended after about six years of operation in 1991 because of excessive water flow.

The Feni gasfield ocated in Feni district and discovered by Petrobangla in 1981 is a small field. Production in the field was suspended in 1998 after about five years of operation.

The Beanibazar gasfield in Sylhet district was discovered by Petrobangla in 1981. It is now producing from 2 wells.

The Fenchuganj gasfield, discovered by Petrobangla in 1988 is a moderate-size field, which has the deepest well in Bangladesh (total depth 4,977m). Some non-commercial oil has been found in this field. The field is not under production now.

The Jalalabad gasfield was discovered in 1989 by Scimitar Oil Company in Sylhet district. The field was later given to Occidental/Unocal oil company. Unocal is now producing from the field.

Table 3  Total reserves and other related data of the gasfields in Bangladesh.

Gasfield Year of discovery Gas initially in place (proven+ probable) billion cu ft Initial reserves (proven + probable) billion cu ft Cumulative gas produced, March 2000 Number of gas zones Gas reservoir depth range (m) Reservoir age and lithology
Sylhet 1955 444 266 165 2 1212-1308 Mio-Pliocene Sandstone
Chattak 1959 447 268 26 6 564-1657 Mio-Pliocene Sandstone
Rashidpur 1960 2242 1309 172 2 1387-2706 Mio-Pliocene Sandstone
Titas 1962 4134 2100 1693 10 2616-3124 Mio-Pliocene Sandstone
Kailashtila 1962 3657 2529 207 3 2281-2990 Mio-Pliocene Sandstone
Habiganj 1963 3669 1895 765 2 1397-3014 Mio-Pliocene Sandstone
Bakhrabad 1969 1432 867 577 4 1826-2144 Mio-Pliocene Sandstone
Semutang 1969 164 98 0 2 980-1279 Mio-Pliocene Sandstone
Begumganj 1977 25 15 0 1 2996 Miocene Sandstone
Kutubdia 1977 780 468 0 1 2650 Miocene Sandstone
Beanibazar 1981 243 167 4 2 3230-3451 Mio-Pliocene Sandstone
Feni 1981 178 125 39 2 1756-2760 Mio-Pliocene Sandstone
Kamta 1982 33 23 21 1 2994 Miocene Sandstone
Fenchuganj 1988 350 210 0 NA NA Mio-Pliocene Sandstone
Jalalabad 1989 1195 836 29 3 2503-2708 Mio-Pliocene Sandstone
Narsinghdi 1990 194 126 25 2 2907-3157 Mio-Pliocene Sandstone
Meghna 1990 159 104 18 6 2293-3017 Mio-Pliocene Sandstone
Shahbazpur 1995 514 333 0 NA NA Mio-Pliocene Sandstone
Sangu 1996 1031 848 58 6+ NA Mio-Pliocene Sandstone
Saldanadi 1996 200 140 11 NA NA Mio-Pliocene Sandstone
Moulvibazar 1997 500 400 0 NA NA Mio-Pliocene Sandstone
Bibiyana 1998 3150 2400 0 7+ NA Mio-Pliocene Sandstone
Total 24,745 15,527 3,810

Source  Petrobangla, unpublished Government and oil company reports.

The Narsingdi gasfield and Meghna gasfield are located north of Bakhrabad gasfield in the Meghna floodplain area. Discovered in 1990 by Petrobangla, both the fields are small in size and have been under production since 1996 and 1997 respectively.

The Sangu gasfield was discovered by Cairn Energy in 1996, now being operated by Shell Oil Company, is the only offshore field which is in production. It is located about 50-km southwest of Chittagong city and stands at a depth of 10 metres of water in the Bay of Bengal. The Bibiyana gasfield, located in Habiganj district, is a very large field discovered by Unocal. It has a GIIP of about 5 Tcf with a recoverable reserve of 2.4 Tcf. Unocal plans to develop the field in the near future.

The Maulvi Bazar gasfield, located in Maulvi Bazar district near Sreemangal, and is known for the Magurchhara blow-out accident in its first well drilled by Occidental/Unocal. A large amount of gas was lost to the atmosphere due to the blow-out in 1998. Later the companies discovered gas in well no 2. The field is yet to be developed. [Badrul Imam and M Lutfar Rahman Chowdhury]

Gas pipeline Immediately after the production of natural gas from the gasfields, it is necessary to have gas flowing through pipelines. Such pipelines are installed according to supply and demand. Transmission and distribution companies have been formed for the purpose. Bangladesh possesses an extensive and long-established gas network. An extensive pipeline network brings gas to consumers, including industrial, commercial and domestic users of natural gas. Among the industrial users of gas, power generation companies consume the major share of the total gas produced. In addition, fertiliser and cement factories, pulp and paper mills and other industries mainly located in the eastern and central parts of the country use natural gas.

Three transmission and distribution companies are currently supplying gas to three franchise areas (a) Titas Franchise Area (TFA), (b) Jalalabad Franchise Area (JFA) and (c) Bakhrabad Franchise Area (BFA). These three areas are separately responsible for supplying gas to - (a) TFA: Ashuganj Power Station, Zia Fertiliser Factory, Jamuna Fertiliser Factory, Ghorashal Urea Fertiliser Factory, Ghorashal Power Station, and Mymensingh, Kishoreganj, Netrokona, Jamalpur and Sherpur districts; (b) JFA: Kumargaon Power Station, Sylhet Paper and Pulp Mills, Chhatak Cement Factory, Ainpur Cement Factory, private sector cement factories, industrial, commercial, domestic and other consumers in Sylhet, Chhatak, Sunamganj districts and adjoining areas, Fenchuganj Power Station, Shahjalal Fertiliser Factory, Habiganj and Maulvi Bazar areas (Shahjibazar Power Plant, Tea gardens and others); (c) BFA: kafco, CUFL, Raozan Power Plant, Sikalbaha Power Plant, Karnafuli Paper Mills, Chittagong, Comilla, Laksham, Feni areas (industrial, commercial, domestic and others).

At present, the Gas Transmission Company Limited (GTCL) is operating the 178 km Kailastila to Ashuganj pipeline (60.96-cm dia) and the North-South Gas Transmission Pipeline. GTCL is also operating the 58 km Ashuganj to Bakhrabad Pipeline (76.20 cm dia), which was constructed and commissioned in 1997. It is also extending the transmission network to Beanibazar gasfield as well as on the western side of the jamuna river. All the gas transmission pipelines that are part of the national gas grid are in the process of being transferred to GTCL.

In all these franchise areas gas demand may rise to 25.65 million cu m/day. The Beanibazar-Kailastila Gas Pipeline, under construction, will also require 1.12 million cu m/day gas in future. Thus the net total gas demand will rise to (25.65 + 1.12) 26.77 million cu m/day. In the near future gas flow will increase by another 7.28 to 7.56 million cu m/day and simultaneously the gas pipeline should increase accordingly. There is a subsidiary company of Petrobangla, the Rupantarita Prakritic Gas Company Ltd, which was formed in 1991 with the objective of developing and popularising CNG in the country. [M Lutfar Rahman Chowdhury]

Gas marketing' Production and marketing of natural gas in Bangladesh started in 1960 with pipeline gas supply from Chattak gasfield to Chattak cement factory. In 1961, a second gasfield, Sylhet, was put under production to supply gas to Fenchuganj fertiliser factory. In 1961, the total gas produced was 3.5 billion cubic feet. Production and marketing of gas in the country has grown steadily ever since. By the end of 1998, the number of gasfields discovered reached 22, with 12 fields under production. In 1998, total production of natural gas in the country was 298 billion cubic feet. The present rate of gas production is about 1,000 million cubic feet per day.

In 2001, production of natural gas in Bangladesh is carried out by three Petrobangla subsidiary companies (BGFCL, SGFCL, BAPEX) and two international oil companies (Shell and Unocal). There are several gas transmission and distribution companies (TGTDCL, BGSL, JGTDSL) responsible for bringing gas to the power plants, fertiliser factories, different industrial, commercial and domestic end users through an extensive network of pipelines.

Power generation and fertiliser production consumes about 80% of the natural gas produced at present. The sectorwise use of gas as a percentage of total gas consumed stands as follows: power (45%), fertiliser (35%), industrial, commercial and domestic (20%). The demand for natural gas in the country is increasing at a rate of 13.4% annually.

The options of natural gas marketing for sectors other than the above-mentioned have been discussed in several quarters including government, private and international organisations. Although the use of natural gas in the petrochemical industry, for LNG, or more recently as a synthetic liquid fuel (by gas to liquid technology) has been in practice in many parts of the world, these options are not considered in the present context of Bangladesh. Instead, the possibility of pipeline gas export is being seriously discussed and debated.

The pipeline gas export option is most vigorously campaigned by foreign oil companies engaged in gas exploration in Bangladesh. The proponents of gas export say Bangladesh should avail herself of the opportunity of a gas market that exists in neighbouring India, where the growth of gas demand is not being met by local supply. It is suggested that Bangladesh should earn foreign exchange to boost its economy by exporting its natural gas to India. The proponents also suggest that in the not so distant future, gas will become a backstage fuel and may not have its present value due to the advent of alternative sources like solar energy.

A second view held by a large section of national experts and politicians, tends to strongly oppose the option of pipeline export at present. The opponents of pipeline gas export point out that two factors should be considered seriously before export to a foreign country is contemplated. These are (i) whether Bangladesh holds enough reserves to meet its future demand, and (ii) the future of natural gas as a fuel.

According to the opponents of gas export, the country's present gas reserve of 15 Tcf is modest and will perhaps be enough to meet the need of the immediate future, but not enough to meet the long-term future demand of the country. Bangladesh has been very much dependent on natural gas as its primary commercial fuel. It has no significant oil reserve, no prospect for further hydroelectric projects and the possibility of having nuclear power is as remote as ever. In the above context, natural gas will remain the sole source of commercial energy for a long time to come. If Bangladesh starts exporting natural gas now the present reserve may well be exhausted before an alternative energy source is in sight. This will be catastrophic for the future energy scenario of the country. The risk of depleting the gas reserve outweighs the short-term economic gain that may be achieved by pipeline export.

Regarding the future of gas as a fuel, international energy experts say that oil and gas will remain the prime energy source till 2040, after which natural gas will be the near universal fuel. The use of natural gas will peak in 2050 following which its use will exceed that of oil and gas together. The take-off point of solar energy or other alternative energy will be delayed and will come before 2050. The opponents of gas export have suggested that Bangladesh should wait for a substantially large reserve to be discovered before considering gas export. [Badrul Imam]

See also hydrocarbon; hydrocarbon exploration;hydrocarbon generation; hydrocarbon reservoir.