Punjab Agricultural University has come up with a technology of producing biogas from paddy stubble using the dry fermentation technique to check the air pollution caused by burning of paddy stubble across the state.
After getting approval from the research evaluation committee, PAU scientists are all set to introduce the new technology in fields for final trials. They view the proposed biogas power plants as the most viable solution to the problem of burning of paddy stubble, a practice banned in Punjab.
"PAU is strongly against burning of paddy straw. We had been working on alternative methods and technologies for the past several years, but the efforts were not paying off. More than 80% farmers in Punjab still burn paddy straw despite all our efforts to sensitise them about the ill-effects of this practice. Now our researchers have finally found an answer to this problem," a PAU official said.
Although PAU had earlier launched technologies like happy seeder, based on no-tillage technology and machinery, for bailing the straw, they failed to make an impact among farmers due to high cost and poor availability.
Dr BS Sooch, director, School of Energy Studies, PAU, said, "At present, the only practical alternative to burning of paddy straw is the biomass plants installed by the Punjab Energy Development Authority (PEDA) four-five years ago. In these plants, the paddy straw is burnt in boilers to produce electricity. But the major problem here is disposal of ash. Besides, the quantity of paddy straw that can be used in this process is very low. Paddy straw only makes up for 20% of the raw material used in the process. The rest of it comes from waste material of other crops like cotton."
Sooch said they had now worked on a new technology based on anaerobic digestion, where paddy straw would be decomposed in the absence of oxygen to produce biogas, which can be used for numerous purposes like cooking and running generators. "The best part is that the residue can also serve as manure. It is a completely non-polluting and eco-friendly technology."
BKU chief for commercial plants in all villages
The biogas plants will be installed in fields of Patiala for final trials. All farmers need to do is install a digester and a gasholder at a cost of Rs 50,000. Small farmers are likely to get subsidy. However, Bhartiya Kisan Union president and Punjab Mandi Board chairman Ajmer Singh Lakhowal said though he was in favour of this technology, it would not be successful at the individual level. "Every farmer cannot install this plant. There should be one commercial plant in every village, where farmers can sell their straw, and the government, after producing biogas, must supply it to all the households in the village," he suggested.