4.1. Emission sources

As there is no data on air pollution available in Bhutan, the information in this section is based on estimates done by the team (see annex 1).

According to the National Communications drafted for the UNFCCC, total emission of greenhouse gases for 1994 are as reflected in Table 4.

Table 4: Total emission of greenhouse gases in Bhutan for the year 1994:

Sources CO₂ N₂O

(Gg) (Gg)

Energy 91.90 0

Fuel Combustion 91.90 0

Fugitive emission NE 0

Industrial Processes 159.69 0

Agriculture NE 1.40

Land Use change and Forestry (-) 48,910.29 NE

Source: Draft National Communication inventory report. (Based on the Global Warming Potential values of the CO₂ equivalents, the methane and nitrous oxide emission are 256.62 Gg. and 434.00 Gg. respectively [GWP values of CO2 equivalent for methane is 21 and nitrous oxide is 310 (SAEFL)).

4.2 Energy consumption statistics

The energy sources of the country are primarily hydropower, fuel wood and fossil fuels such as kerosene, diesel, petrol, and liquid gas petroleum. There are a few installations of biogas fuel, solar and wind energy but their use has not yet become prominent. There is one coal mine in Bhutan. 99% of the coal mined is exported. It is estimated that less than 0.5 Gg. of methane is emitted during mining operations. Coal constitutes less than 0.01% of total energy consumption in the country..

Table 5: Mega tonnes of Oil Equivalent of Energy Consumption

Note: "X" refers to figures less than 0.01

Source: Statistical Yearbook of Bhutan, 1997. (Mtoe: Mega tons of oil equivalent)

Total consumption of energy was around 2 mega-tonnes of oil equivalent. In 1997, 95% of all energy produced in the country comprised of hydroelectric. Hydropower has become the predominant source of energy since the commissioning of the Chhukha Hydro Power Project in the 1980s. Hydro-electricity will continue to be the major source of energy in Bhutan. Biogas is quite insignificant at the moment although it has been tried in various parts of the country.

Liquid petroleum, petrol, diesel and kerosene are imported. There has been a gradual increase in the consumption of these fuels since 1990 (CSO yearbook 1998). This has been due to the growing urban population and increases in the number of vehicles and industries. Micro-hydels and solar energy technologies have been tried by the government to reduce dependency on fossil fuels.

Table 6. Current sulphur dioxide emission estimates by sectoral breakdown, for 1998
 

Sector	SO2 Emission  (tonnes/year)
1. Industry	12.1
2. Transport	2,158.5
3. Domestic	3,320.8
4. Power generation	N.A
5. Fuel conversion	N.A

Source: Estimations based on data provided by sectors (CSO Year book 1998)

Table 7. Current sulphur dioxide emission estimates (tonnes/year) by sector and source type for 1998
 

Sector	Point source	Area source	Both sources
1. Industry	..	..	12.1
2. Transport	..	..	2,158.5
3. Domestic	..	..	3,320.8
4. Power generation	..	..	N.A
5. Fuel conversion	..	..	N.A

Source: Estimations based on data provided by sectors (CSO Year book 1998)

Table 8. Emission from mobile sources, Bhutan, 1998
 

Vehicle category	Number of vehicles
LPG vehicles	0
Motor cycles Motor cycles – 2 stroke Motor cycles - 4 stroke	8,200 8,200 n.a
Gasoline cars Gasoline cars (<1.51) Gasoline cars (1.5-2.01) Gasoline cars and light trucks (>2.01)	3,600 n.a n.a n.a
Heavy trucks – gasoline	0
Buses (gasoline)	0
Diesel cars  Diesel cars (<1.51) Diesel cars (1.5-2.01) Diesel cars and light trucks (>2.01)	3,500 n.a n.a n.a
Heavy vehicles Heavy trucks (diesel) Buses (diesels) Other motors	2,600 n.a n.a 300

Note: "Light vehicles" include cars, vans, light trucks.

Source: Road Safety and Transport Authority, Bhutan

Table 9. Emission source of NO_x from Industrial process, Bhutan, 1997
 

Process	Production(tonnes/yr)	Emission factor
1. Metal production 2. Paper & pulp 3. Domestic 4. Land use 5. Fuel combustion 6. Forests fires	7.2 .. 3.8 38.1 29.6 13.0	30g/ton product .. 100 kg/TJ 100 kg/TJ 100-800 kg/TJ 100 kg/TJ

Source: Estimations made based on the data from sectors. (CSO Year book 1998)

Table 10. Sectoral breakdown of emission of NO₂, Bhutan, 1998
 

Sector	Emission (tonnes NO2 equivalent / yr)
1. Industry	7.2
2. Transport	29.6
3. Domestic	54.9
4. power generation	..
5. Fuel conversion	..

Source: Estimations made based on the data from sectors. (CSO Year book 1998)
 
 

Table 11. NO₂ emissions by source, Bhutan, 1998
 

Source type	Emission ('000 tonnes NO2 equivalent/yr
1. Point source	..
2. Area source	..
Both sources	91.7

Source: Estimations made based on the data from sectors. (CSO Year book 1998)

4.3. Fuel wood

The consumption of fuel wood is very high in Bhutanese society. A projected domestic fuel wood consumption by MPFD 1991 is as high as 1.92 M³ per capita. The firewood used for fuel is reported in statistics maintained by the FSD but manual collection in the rural areas is not recorded.

4.4. Transport

The chief mode of transport in Bhutan is road transport. As of 1994, there were 1,295 motor cars, tractors, power-tillers and heavy machinery (PMT, 1997). In 1994, Bhutan imported 12.94 Kt. of diesel and 2.34 Kt. of petrol. 9.78Kt of the diesel imported was used by the transport sector.

4.5. Others

In 1994, Bhutan imported 5.19Kt of kerosene and 3.61Kt of LPG. Both LPG and kerosene are used in urban and rural areas for lighting and cooking.

Road paving in Bhutan is another source of SO₂ and NO_x emission as new roads are continually being constructed and old ones repaired. In 1999, about 1,700 metric tons of bitumen was imported and used for road surfacing.

Besides transport vehicles there are also 20 power-threshers, 975 grain mills, 65 oil expellers and 94 essential oil units in Bhutan (LUPP, 1994). Most of these agriculture machinery use diesel fuel and are based in rural areas. As a result fuel consumption statistics are not available.

4.6. Trends in emission

Although no scientific data is available to determine the exact trends in emission, air pollution is a growing concern in Bhutan, especially in urban areas. The rise in the income level of the people has led to an increase in the number of vehicles. The number of industrial units is also increasing. Most of the industrial units were set up before the establishment of NECS and institutionalization of the environmental assessment process.

Majority of the people is still dependent on firewood for cooking and heating. As a result urban air pollution is very evident in towns like Thimphu, especially during the winter months when temperature inversion compounds the problem.