The first ever largest biogas plant in the country with 75 production capacity installed using pig manure at the National Piggery Development Centre (NPiDC), Gelephu is functioning well. It was installed in collaboration with the Bhutan Biogas Project/SNV. The bio-gas plants installed in the various districts does not have more than 6 production capacity.
The main purpose of such installation is to contribute towards the climate change issues and control the piggery foul smell. Moreover, with a rapid expansion of Gelephu municipality in Jampelling Demkhong, there are chances of displacement of present nucleus pig farm, if such odour reduction measures are not taken.
The piggery waste produce from 700 farm animals is used for daily re-filling of the plant. Presently, the bio-gas produced is utilised for light, heat generation at pig sheds and is connected to 10 kitchens of animal attendants, staff quarters and office building.
Although, it would be difficult to quantify the reduction of emission of green house gases to environment, the immediate impact noticed is in reduction of farm odour and an improvement in farm hygiene. The electricity utility bill is reduced and about 30 liquid petroleum gas re-filled cylinders are expected to be reduced annually, which would otherwise cost approximately Nu. 15000 per year if imported. In the past, pig dung was either washed away to outlet drain or left in open for natural drying.
NPiDC plans to install similar bio-gas plant at the Regional Poultry and Pig Breeding Centre, Lingmithang.