Waste to energy: an overview by global perspective

In this present era, amount of diverse types of waste is increasing day by day. For the insufficient and improper management of waste recycle system, global environment is being polluted tremendously. Every year, approximately 2.12 billion tonnes, a massive amount of waste is being dumped to the open environment worldwide. In this alarming scenario, as intensity of carbon emission is intensified, invention of bioenergy is hailed as a great accomplishment to transform waste to green energy that is environment-friendly and as well as sustainable. In this chapter, a worldwide scenario of both organic and inorganic wastes such as plastics, rubbers, e-waste, numerous biomass wastes, and others has been discussed comprehensively. Various conversion technologies: esterification, trans-esterification, anaerobic digestion, catalytic pyrolysis, and others are emphasized simultaneously in this study. This chapter also highlights perspective and economic potential of different forms of bioenergy such as biodiesel, bioethanol, bio-gas, and others. The review also concerns a detail discussion on greenhouse gas emission reduction upon consumption of bioenergy instead fossil fuels. Along with that, applications of bioenergy in electricity and transportation sector are also showcased. Moreover, projection of the sustainability of waste to energy for upcoming decades has been outlined.