As nations strive toward achieving sustainability and reducing reliance on fossil fuels, biomass has emerged as an indispensable component of worldwide energy portfolios. Biomass, derived from organic materials such as plants, agricultural residues, forestry byproducts, and organic waste, is a renewable energy source and abundant resource with significant potential across various sectors. Responsible biomass energy production can aid in waste management, reduce greenhouse gas emissions, and mitigate environmental pollution by utilizing organic materials that would otherwise be discarded. With the anticipated growth in biomass use for energy, it is essential to establish analytical techniques for assessing the quality of the fuel feedstock materials. This will enable to better comprehend the implications of using biomass fuels on public health and our ecosystem. One such technique is reflected light microscopy, which has the potential to significantly enhance the conventional (physical and chemical) quality assessment of biomass-derived fuels. This technique enables rapid observations of material constituents and identification of impurities, and it can be applied not only to fuels but also to biomass-based pellets used in animal feed and bedding. Given the scarcity of publicly accessible microscopic images of biomass materials, the “Atlas of Microscopic Images of Raw Biomass” fills this gap by offering a comprehensive collection of 553 images. These photomicrographs capture the optical characteristics of a diverse array of biomass feedstock, demonstrating unique morphological and structural features. This visual documentation can serve as a valuable resource for researchers, industry professionals, educators, and enthusiasts interested in investigating the complexities of biomass forms.
