Trends in harnessing energy from waste biomass: pathways & future potential

Demand for fuel energy is continually on the rise. There is also a constant challenge involved to ensure that all our energy needs are fulfilled. Persistent overconsumption of conventional fossil fuels due to the rise in global population aided by economic expansion has resulted in reduction of fossil fuel reserves. This has fuelled the need to boost research efforts on renewable and sustainable bioenergy feedstocks. Since bioenergy utilizes organic matter; therefore, it is an economically viable and clean solution, which can minimize our reliance on non-renewable resources. The bioprocessing of lignocellulosic biomass to produce bio-based products under biorefinery setup is gaining global attention. The main challenge however remains to strike a balance between energy harvesting and economic viability with minimum environmental impacts. The development of zero-waste lignocellulosic biorefinery aligns completely with the idea of sustainable development without increasing carbon footprint. This concept is self-sustainable. It also advocates re-usage or recycling of waste; of which using lignocellulosic biomass waste is a major thrust. Improving the techno-economic efficiency of currently employed pretreatment methods and looking for combined pretreatment strategies will prove to be a stepping stone in the commercialization of zero-waste lignocellulosic biorefineries. This review investigates the most widespread pretreatment types, highlighs their advantages/disadvantages, and reviews the current status and technological advances in the bioconversion process of LCB into bioenergy in a biorefinery set-up.