Biogas for a sustainable future
by ALBERT FERNANDES
CANACONA: Biogas technology is being promoted in India chiefly under the aspect of energy. It is based on the anaerobic digestion of organic material to produce clean fuel for cooking, lighting and running machinery.
The bio-digested slurry besides providing plant nutrients, benefits the soil by bringing about physical, chemical and biological enrichment. In the days of energy crisis, biogas becomes handy for the farming community as it supplies gas for fuel and enriched bio-manure from cow dung.
Looking beyond the years, it seems certain that we are moving to an era when the energy costs are going to rise and the pressure on fossil fuels and wood is going to become more and more acute.
The rising commercial energy demands worldwide also threaten the environment. Power sector growth is estimated to come mainly from fossil fuels, coal, oil, gas and large hydropower developments. Renewable energy resources and energy efficiency can help address some of the global growing energy needs without adverse environmental impacts.
So why should people today prefer biogas plants in their homes? Precisely because of its zero or low cost fuels, low gestation period, quicker benefits, social relevance and economic viability, besides providing security to developing economies. The biogas energy is comparatively cheaper as compared to conventional sources.
Biogas plants can be easily installed in remote tribal areas where electricity is not viable and/or available. It can also help in the reduction of indiscriminate felling of trees for fuel and consequent deforestation, besides improving rural sanitation and reducing the incidences of eye-diseases among the village women and children. biogas plants, if installed in the rural remote areas, offers huge employment for the less-skilled rural people.
Speaking to this reporter, the ZAO Canacona, Mr Rajesh Desai informed that biogas production, like the septic tank, is an anaerobic digestive process, which is the simplest and safest way for treating human excreta and animal manure to prevent the spread of diseases. He also informed that it converts these renewable resources to a clean fuel to replace other conventional fuels. When burnt, biogas gives a blue flame which may be used for cooking, lighting as well as alternative fuel for petrol and diesel engines.
Mr Desai points out that biogas technology also reduces the build-up of carbon dioxide in the atmosphere and reduces the smoke in the area. He further tells that a biogas plant is an asset to a farmer’s family, because it is based on the biological decomposition of organic materials in the absence of air. Since India has the largest cattle population in the world, this strategy can work and is viable to the Indian rural community in particular.
Mr Desai further informs that there shouldn’t be big trees near the selected sites for the installation of biogas plants since this may prevent the sun’s rays from falling on the plant. The roots, too, may cause damage.
The ground water level should be at least 2-3 metres below the surface and the selected site shouldn’t have in its vicinity a drinking water well, for at least 50 feet around. There should be enough space for storage of digested slurry pits or construction of compost pits, Mr Desai asserted.
Mr Desai also pointed out that septic tanks can be connected to biogas plants. He confirmed that in Belgaum, most of the septic tanks have been connected to biogas plants.
Moreover, the government gives 90 per cent subsidy for the construction of a biogas plant. On an average per day, 15-25 kg of cow dung is sufficient to run a domestic biogas unit in one household.
Today, in Canacona taluka, there are more than 50 installations of biogas plants.