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would be available since the number of animals also include households with only one cattle or buffalo and
hence do not have enough dung volume to feed the smallest size biogas plant (4 m 3 ) which requires 24 kg of
dung per day. These calculations do not take account of the dung available from poultry and other domestic
animals such as pigs and goats. A quick review on above data will reveal that there would be potential of 2.9
million biogas plants in Nepal. In 1992, based upon the potential of biogas plants in the plains, hills and
mountain, Wim J. van Nes had calculated the potential of establishing 1.3 million in the Kingdom of Nepal.
On the other hand, although the assumptions on the technical potential may range between 1.3 and 2.9
million plants (CMS and SNV/BSP), the economical potential is considered to be 600,000 plants.
Introduced in Nepal in the 1950's, biogas technology has spread rapidly in 66 districts out of 75 during the
last few years, increasing the cumulative number of plants installed to 1,23,395 by 31 December 2004. Thus,
considering the economic potential and number of biogas installed up to 1999, there is a long way to go as
vast number of potential (87.6 percent) still remains to be trapped (see Figure 13.4). While such a huge
energy potential remains unused which otherwise could have enhanced the rate of employment and the
level of rural income, the rural communities continue to face energy starvation with an estimated
economic potential of 600,000 units.
13.1.3 Biogas Production
a. Biogas Production
Figure 13.4: Current Biogas Saturation in Nepal
As of December 2004, total number of biogas installed in the Kingdom of Nepal was around 1,23,395 out of
which 62,160 plants were installed under the umbrella of BSP. The survey carried out by SNV/BSP indicates
that the average plant volume has been decreasing since 1992 and is around 7 m 3 at the present moment
(Felix ter Heedge, SNV/BSP). Mr. Felix made following assumptions for calculating the total installed
volume of biogas plants in Nepal:
■ Average feeding = 6.72 kg per m 3 ;
■ Average gas production = 0.036 m 3 /kg of dung;
■ Average feeding = 82%;
■ Season correction = 90%; and
■ Rate of operation = 97%
b. Cost of Energy Option
As for the cost of energy option, the cost of energy production of biogas per MW has been compared with the
hydropower schemes, for example, Modo Khola Hydro Project and Arun 3 Hydro Project. The data
presented in Figure 13.5 reveals that in case of biogas, the cost of production per MW is NRs 79.4 million,
whereas Modi Khola Hydro Project and Arun 3 Hydro Project cost NRS 143 million and NRs 238
million respectively. This shows clearly that biogas is the cheapest option so far as cost of energy
option is concerned.
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