<p>The emphasis on resource efficient and low-carbon-based energy systems is premised on biomass-to-energy (BTE) technologies. To focus on the newest advancements in the biomass-to-energy conversion, the following paper will review the advances concerning the biomass-to-energy conversion with a specific focus on eco-effective processes, which are facilitated by the newly developed bio-based materials. The primary features that are taken into account are feedstock biomass nature, main conversion routes, i.e., thermochemical, biochemical, physicochemical routes and material development that enhances conversion efficiency, durability, and environmental behavior. Another element employed in the review is the implementation of life-cycle assessment (LCA) to provide a critical analysis of the environmental effects, economical and scalability of biomass energy systems. Laboratory-level developments and pilots are synthesized in a methodical fashion in order to be aware of the technical bottlenecks and knowledge gaps. Finally, the paper discusses issues of policy implications and sustainability, and plans to improve the rapid implementation of the biomass to energy systems in the large scale with minimal environmental trade-offs and maximizes the benefits of the cyclical bioeconomy.</p>