The requirement of energy continues to grow as a result of increase in population and size of the economy. Fossil energy is adjudged unsustainable due to the damaging environmental effects such as global warming. Therefore, several alternatives that are less harmful are considered, among which bioenergy is at the top. This is a form of energy that is derived from biomass and comes in various forms including biodiesel, bioethanol, and biogas. The production of biofuel involves feedstock (raw material) processing that can be thermal, mechanical, chemical, and biological. The biodiesel can be generated from oil crops and vegetable and animal fats. The fatty acids must be transesterified. For bioethanol, feedstock that are rich in carbohydrates are used. They are sugar and starch crops as well as lignocellulosic biomass. Sugar crops are crushed, and the fermentable sugars are converted to ethanol by yeast. In the case of starch, it is hydrolyzed to glycans and saccharified to sugars, and the fermentable sugars are then converted to ethanol. Conversion of lignocellulose biomass to ethanol is tasking; this is because pretreatment is required due to the recalcitrant nature of lignin. Then, the cellulose is accessed as hydrolyzed to sugars that can be converted to ethanol. Biogas production can be achieved using the crops as well as animal wastes such as cow dungs; however, some microorganisms may be required to facilitate the process. Moreover, efficient bioenergy generation is hindered by several factors such as availability and cost of raw material, catalyst and enzyme utilization, design, and use of reactor systems. © 2024 Elsevier Inc. All rights are reserved including those for text and data mining AI training and similar technologies.