Overview of electric power potential of surplus agricultural biomass from economic, social, environmental and technical perspective-A case study of Punjab

Biomass is a renewable, economic and readily available resource of energy that has potential to substitute fossil fuels in many applications such as heat, electricity and biofuels. The increased use of the agricultural biomass can help the agricultural based societies in achieving energy security and creating employment without causing environmental degradation. But, the viability and feasibility of electricity generation from agricultural biomass depends upon the availability of biomass supply at a competitive cost. The present study investigates the availability of agricultural biomass for distributed power generation in Punjab. The total production of the crop residues has been estimated by residue-to-product ratio (RPR) method. Further, the restrictions introduced by competitive uses as well as harvesting practices are taken into considerations to evaluate the available biomass potential. The biomass power potential has been obtained on considerations of energy contents of the particular crop residues and selecting appropriate conversion route. A total of 55.396 Mt of the agricultural residues are produced from various major crops. Out of these, 22.315 Mt (40.17%) of the agricultural biomass has been found to be surplus with an average density of 443 t/km2. These surplus residues can significantly be used to provide continuous, reliable and sustainable fuel supply for power plants. Cereals (rice, wheat, maize and barley) have major contribution (74.67%) in the surplus biomass, followed by cotton (25.01%) and sugarcane (0.2%). The estimated annual bio-energy potential of unused crop residues is 0.35 EJ (8.43% of India's potential), which is equivalent to 1.43% India's annual primary energy consumption. It has been revealed that a power potential of 2000-3000 MW can be exploited from these resources depending upon thermal efficiency. The study concludes with a discussion on significance and challenges of decentralized electricity generation for rural energy supply, including brief description about economical, social, environmental and technical aspects of bioelectricity.