Turning paddy straw into Compressed Bio Gas
- A renewable energy revolution in agriculture has started in India with the first bio-energy plant in Punjab having commenced commercial operations recently.
- Will produce Compressed Bio Gas (CBG) from paddy straw.
About the plant
- Will utilise about 2.1 lakh tonnes of a total of 18.32 million tonnes of paddy straw annually.
- Paddy residue will be collected from this year to produce 33 tons of CBG and 600-650 tonnes of fermented organic manure/slurry per day.
- Will reduce up to 1.5 lakh tonnes of CO2 emissions per year.
Background
- Farmers in Punjab, Haryana and western UP dispose of paddy stubble and the biomass by setting it on fire to prepare fields for the next crop.
- The resultant clouds of smoke cause pollution and visibility issues in the NCT of Delhi.
- Pollutes environment and affects human and livestock health.
Commission for Air Quality Management in NCR (CAQM) efforts
- A Framework and action plan by CAQM
- For effective prevention and control of stubble burning.
- In-situ efforts:
- Incorporation of paddy straw and stubble in the soil using machinery.
- Ex-situ CRM efforts:
- Use of paddy straw for biomass power projects and co-firing in thermal power plants
- As feedstock for 2G ethanol plants, CBG plants, waste-to- energy (WTE) plants
- As fuel in industrial boilers
- In packaging materials
- Issues:
- Despite these efforts, farm fires continued unabated.
- Crop residue burning is spreading even to rabi crops and the rest of the country.
NITI Aayog and FAO India efforts
- 2019- NITI Aayog approached FAO India
- Aim: to explore converting paddy straw and stubble into energy
- FAO published its study on developing a crop residue supply chain in Punjab.
- Can allow the collection and final use of rice straw for other productive services (for production of renewable energy).
- To mobilise 30% of the rice straw produced in Punjab, an investment of around > ₹2000 crore would be needed.
- Would reduce greenhouse gas (GHG) emissions by about 9.7 million tonnes of CO2 equivalent and around 66,000 tonnes of PM2.5.
- Farmers can earn between ₹550 and ₹1,500 per ton of rice straw.
What can be done and benefits from it
- Cost-effective for producing CBG and pellets.
- 30% of the rice straw produced in Punjab
- A 5% CBG production target set by SATAT scheme can be met.
- Could also increase local entrepreneurship, farmers’ income and reduce open burning of rice straw.
- Paddy straw from 1 acre of crop can yield energy output (CBG) worth> ₹17,000 - ideal example of a ‘wealth from waste’ approach
- Slurry or fermented organic manure is useful as compost to replenish soils heavily depleted of organic matter.
- Will provide employment opportunities to rural youth.
Conclusion
- A first win-win initiative in the form of environmental benefits, renewable energy, value addition to the economy, farmers’ income and sustainability.
- This initiative is replicable and scalable across the country and can be a game changer for the rural economy.
Prelims takeaway
- SATAT scheme
- FAO
- CBG