Sweet Sorghum as First-Generation Biofuel Feedstock and Its Commercialization

Sweet sorghum (Sorghum bicolor (L.) Moench), a sugar crop with wider adaptation and high potential for bioenergy and ethanol production, is expected to meet food, feed, fodder, fuel, and fiber demands. Most of the crops are vulnerable to climate change, but sweet sorghum is both a smart and a resilient crop because of its ability to perform well in adverse climatic conditions. This crop is expected to yield more ethanol per unit area of land than many other crops especially under minimum input production. It is well adapted to marginal growing conditions such as water deficits, salinity, alkalinity, and other constraints. Some sweet sorghum lines attain juice yields of about 78% of total plant biomass, containing from 15 to 23% soluble fermentable sugars which are composed mainly of sucrose (70–80%), fructose, and glucose. Most of the sugars are distributed in the stalk making the crop particularly amenable to direct fermentable sugar extraction. Sweet sorghum has the potential to yield up to 8000 L ha−1 of ethanol or approximately twice the ethanol yield potential of corn and 30% greater than the average sugarcane productivity. Due to its short growing period (3–4 months), sweet sorghum can be grown in sugarcane off-season. It will help farmers to fetch additional income and provide an opportunity for better utilization of industrial facilities during sugarcane off-season. This chapter reviews the attributes that make sweet sorghum a potential bioenergy crop, industrial trials, and the ways and means for promoting the crop as an efficient feedstock for biofuel production.