Community Biogas Plant — For a Healthier Future
Premise
In rural India, around 75% of households still resort to solid fuel burning for cooking purposes, according to National Family Health Survey 2015–16. Indoor pollution may lead to infants’ short lifespan, inhibit healthy development for children, and contribute to cardiovascular diseases. Though women are the most affected ones with respiratory health issues on average, in communities or villages where most households cook with solid fuels, the problems persist with all adults. The burning of solid fuels for household purposes also contributes to a significant part of air pollution.
In 2016, the central government launched Pradhan Mantri Ujjwala Yojana to promote clean cooking fuel such as LPG in rural India. The scheme provides subsidies on LPG connection and provides a free gas cylinder, pipe, and regulator. In December 2018, the government claimed that 90% of all Indian households had received an LPG connection. But numerous reports depict that even with the connection, many homes continue to use solid fuels due to the high cost of refilling cylinders.
Why Biogas?
India has the 2nd biggest cattle inventory in the world. With the ready availability of crop residue, agricultural waste, bio-industrial waste (distillery, dairy, sugar, etc.), poultry, etc., India’s biogas potential is 29–48 billion m3/year. In contrast, the total production is merely 2.07 billion m3/year. India has a vast untapped potential of energy generation from biomass, where it can solve numerous issues related to health, air pollution, waste disposal, and manure generation.
Biogas is a carbon-neutral, particulate-free form of energy that reduces chronic disease associated with indoor solid-fuel combustion. It also negates the addition of harmful gases like SO2, NO2, CO, and suspended particulates matter in the atmospheric air, leading to a reduction in air pollution. The use of biogas will help increase productivity in an agrarian community.
Community Biogas Plant
The Government of India had started a program of building community biogas plants to provide clean cooking fuel to the rural population. Construction of such plants did begin in the states like Punjab, but the same became scattered and non-existent in the current times. With the extent of air pollution in India, Community biogas can help localize the solution to cooking fuel.
Biomass, mainly cattle dung, which is majorly used to make dung cakes, can be used for anaerobic digestion. The plant’s feed can also be mixed with other organic wastes generated from the kitchen and garden. The slurry that returns after methanogenesis is superior in terms of nutrition. The carbon-nitrogen ratio (C:N) is reduced, and a part of the nitrogen is available in the form of nitrate (NO3-) and ammonium (NH4+), which can be easily absorbed by the plants.
Challenges
Majorly, the critical problem that occurs during the design and construction of a biogas plant is its size. People generally build biogas plants that are too large, which causes underfeeding, leading to non-production of gas or inadequate pressure in the dome. Under-collection of cattle dung is also one of the main factors that have been identified mostly due to unforeseen factors such as the sale or death of cattle.
As the existing sources of energy such as wood and crop residues are free, and dung cakes can be sold for extra income, this might hinder the switch to biogas. One major challenge is that women who are most affected by smoke chulhas are not the decision makers in rural households.
There is also significantly less awareness about the use of biogas in rural India. There is a need for policy structure in this field that needs to be implemented at the village/community level and community biogas model can prove a torchbearer in India’s take on pollution and rural health.
References
1. Gupta, A., Vya, S., Hathi, P., Khalid, N., Srivastav, N., Spears, D., & Coffey, D. (2020). Persistence of Solid Fuel Use in Rural North India. Economic & Political Weekly.
2. Kaushik, L. K., Mahalingam, A. K., & Palanisamy, M. (2020). Performance analysis of a biogas operated porous radiant burner for domestic cooking application. Environmental Science and Pollution Research.
3. Nasery, V. (2011). Biogas for rural communities. Mumbai.
