• The beginnings of a renewable energy revolution rooted in agriculture are taking shape in India by the establishment of the first bio-energy plant by a private company in Sangrur district of Punjab.
• It will produce Compressed Bio Gas (CBG) from paddy straw, thus converting agricultural waste into wealth.
• Although despite such efforts from private as well as government entities, farm fires are still prevalent across India, especially in northern India.

CBG

• The Gas produced through the process of anaerobic decomposition of various waste/Bio-mass sources is called Compressed Bio Gas (CBG).
• The waste/Bio-mass sources include:
• Agricultural residue,
• Cattle dung,
• Sugarcane press mud,
• Municipal solid waste,
• Sewage treatment plant waste.
• Supply process of CBG:
• The Bio-Gas is purified to remove hydrogen sulphide (H2S), carbon dioxide (CO2), water vapor and compressed as CBG.
• The CBG has methane (CH4) content of more than 90%.
• Why to utilize CBG?
• CBG has calorific value and other properties similar to CNG and hence can be utilized as green renewable automotive fuel.
• Thus, it can replace CNG in automotive, industrial and commercial areas, given the abundance of biomass availability within the country.

Impact of agricultural waste in environment

• The farmers in Punjab, Haryana and western Uttar Pradesh are following common practice for preparing their fields for next crop like:
• Disposing of Paddy stubble in to the field
• Setting all the biomass on fire after the crop is harvested
• This isn’t limited to the single field as it is spread over millions of hectares.
• The resultant clouds of smoke produced from burning the waste engulfs the entire National Capital Territory of Delhi and neighboring States, giving rise to air pollution in the states.
• This plays havoc with the environment and affects human and livestock health.

Government Initiative

• The Government of India has put in place several measures and spent a lot of money in tackling the problem of farm fires.
• The Commission for Air Quality Management (CAQM) had developed a framework and action plan for the effective prevention and control of stubble burning.
• This action plan is to be implemented in National Capital Region and Adjoining Areas.
• The framework/action plan includes:
• In-situ management:
• Incorporation of paddy straw and stubble in the soil using heavily subsidized machinery
• It is supported by crop residue management (CRM) Scheme of the Ministry of Agriculture and Farmers Welfare.  
• Ex-situ CRM management:
• Usage of paddy straw for:
• Biomass power projects and co-firing in thermal power plants,
• As feedstock for 2G ethanol plants,
• As a feed stock in CBG plants,
• Fuel in industrial boilers,
• Waste-to-energy (WTE) plants,
• For packaging of materials.
• Additionally, measures are in place to ban stubble burning, to monitor and enforce this, and initiating awareness generation.

Challenges

• Despite the efforts taken by the government, the farm fires continued unabated.
• The paddy stubble burning in northwest India has received a lot of attention because of its severity of pollution.
• The reality of the crop residue burning is spreading even to rabi crops and the rest of the country.

Project in Progress

• The NITI Aayog approached FAO India in 2019 for:
• Exploring & converting paddy straw and stubble into energy
• Identifying possible ex-situ uses of rice straw to complement the in-situ programme
• According to a study published by FAO, the development of a crop residue supply chain in Punjab can lead to:
• The collection, storage and final use of rice straw for other productive services
• Specifically for the production of renewable energy
• It suggests that it can also lead to:
• Mobilization of 30% of the rice straw produced in Punjab,
• An investment of around ₹2,201 crore ($309 million) would be needed to collect, transport and store it within a 20-day period.
• This would reduce greenhouse gas (GHG) emissions by about 9.7 million tonnes of CO 2 equivalent
• Reduction of around 66,000 tonnes of PM 2.5.
• Further, depending on market conditions, farmers can expect to earn between ₹550 and ₹1,500 per ton of rice straw sold, depending on market conditions.
• A techno-economic assessment of energy technologies suggested that rice straw can be cost-effective for producing CBG and pellets.
• Pellets can be used in thermal power plants as a substitute of coal and CBG as a transport fuel.
• With 30% of the rice straw produced in Punjab, a 5% CBG production target set by the Government of India scheme, “Sustainable Alternative Towards Affordable Transportation (SATAT)”
• It could also increase local entrepreneurship, increase farmers’ income and reduce open burning of rice straw.
• Punjab, Sangrur, Ludhiana and Barnala were recommended as the most promising districts for these interventions.
• A private company got approval from the Punjab government in April 2018 to set up a bio-CNG project.
• This will utilize about 2.1 lakh tonnes of a total of 18.32 million tonnes of paddy straw annually.
• The plant will use one lakh tonnes of paddy straw produced from approximately 16,000 hectares of paddy fields.
• 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.
• For reducing up to 1.5 lakh tonnes of CO 2 emissions per year.

Benefits of CBG

• As per the SATAT (Sustainable Alternative Towards Affordable Transportation) scheme, CBG valued at ₹46 per kg will be produced from paddy stubble
• Paddy straw from one acre of crop can yield energy output (CBG) worth more than ₹17,000 — an addition of more than 30% to the main output of grain.
• This initiative is an ideal example of a ‘wealth from waste’ approach and circular economy.
• The slurry or fermented organic manure from the plant (CBG) will be useful as compost to replenish soils heavily depleted of organic matter
• That reduces dependence on chemical fertilizers.
• The plant will also Sustainable Alternative Towards Affordable Transportation to rural youth in the large value chain, from paddy harvest, collection, baling, transport and handling of biomass and in the CBG plant.
• This will Sustainable Alternative Towards Affordable Transportation
• It is pertinent to mention that straw from many other crops contains higher energy than paddy straw.

This initiative is replicable and scalable across the country and can be a game changer for the rural economy.