Assessment of electricity generation potential from biochar in Northern India

Abstract

Environment-friendly rice and wheat straw management in the Indian states of Punjab and Haryana have been a significant challenge. Farmers have adopted in-situ burning of crop residues as it is almost out of no pocket expense. However, this practice amounts to releasing 42.32 MT hazardous pollutants and GHGs into the atmosphere, which has an estimated 58.62 MT CO₂e GWP. The present study considered biochar conversion of surplus rice and wheat straw through slow pyrolysis to investigate biochar compatibility for cofiring with coal in power plants. Rice straw derived biochar produced at 400 °C, and wheat straw derived biochar produced at 500 °C were found most suitable for cofiring and electricity generation. It was estimated that about 10.53 MT high quality coal grade biochar could be produced from 28.35 MT of surplus rice and wheat straw in Punjab and Haryana, which has an estimated 19.80 TWh electricity generation potential. Also, electricity generation from biochar would reduce pollutant emissions imparting 30.25 MT CO₂e GWP. The results of this study could provide baseline data for fuel replacement in power plants.