An increased use of biofuels would contribute to sustainable development by reducing greenhouse gas emissions and the use of non-renewable resources. In recent years, it has been suggested that instead of traditional feedstocks, cellulosic biomass (cellulose and hemicellulose), including sugarcane bagasse could be used as an ideally inexpensive and abundantly available source of sugar for fermenta­tion into transportation fuel ethanol. The efficiency of biomass conversion into ethanol depends upon the ability of the microorganism used in the process to utilize these diverse carbon sources and the amount of fraction present in biomass. The cost of ethanol production from sugarcane bagasse is relatively high based on current technologies.

As the price of current ethanol feedstocks (e. g. Corn) is estimated to increase, lignocellulosic materials remain the only viable candidate to serve as renewable feedstock for ethanol production. There are huge amounts of wheat straw that are currently burnt in the field or wasted otherwise which can be used as low value raw material for ethanol production. Despite extensive technological advances in ethanol production from lignocellulose feedstocks over the last few decades, the price of the second-generation ethanol is still high and remains around $2.65/ gallon [101, 102]. This high price is because of some technological impediments encountered in all the different steps of the process. Pretreatment is estimated to account for 33% of the total cost [187]. The current leading pretreatment methods for lignocellulosic materials are capital intensive. Economical comparison showed that there is little differentiation between studied pretreatment methods as for instance; low cost pretreatment reactors are counterbalanced by higher cost of catalyst and/or ethanol recovery [42]. Development of less energy intensive and more effective pretreatment methods allowing lower amount of enzymes loading can substantially decrease the total cost of cellulosic ethanol.

The utilization of lignocellulosic biomass for bioethanol production necessi­tates the production technology to be cost-effective and environmentally sustain­able. Considering the evolution and need of second-generation biofuels, rice straw appears to be a promising and potent candidate for production of bioethanol due to its abundant availability and attractive composition. Biological conversion of rice straw into fermentable sugars, employing hydrolyzing enzymes is, at present the most attractive alternative due to environmental concerns. Although there are several hindrances in the way of developing economically feasible technology due to its complex nature, high lignin, and ash content, work is going on to develop an efficient pretreatment method to remove unwanted portions so as to get readily available sugars and a considerable success has been achieved till date. The available statistics show that the need of bioethanol for the transport sector could be met by using rice straw. Approaches in both process engineering and strain engineering still have to be carried out to circumvent the difficulties of xylose and glucose co-fermentation and to improve the system efficiency. A very balanced and intelligent combination of pretreatment, hydrolysis, and the fermentation process has to be selected for maximum efficacy of the process. With the advent of genetically modified yeast, synthetic hydrolyzing enzymes, other sophisticated technologies and their efficient combination, the process of bioethanol production employing rice straw will prove to be a feasible technology in the very near future.