This unit concentrates on the role of biological engineering and biomanufacturing in solving the challenges associated with producing biofuels in a sustainable and environmentally friendly manner. The focus of this unit is on the biomanufacturing of biofuels from algae and cellulosic plant materials. The unit begins by examining global consumption of fossil fuels and energy from renewable sources. Students conduct a household energy audit to contextualize their energy consumption patterns. They investigate the process of photosynthesis and its role in the formation of both fossil fuels and biofuels. Applying an engineering design process, students are challenged to design, build, and operate benchtop scale algae bioreactors. Students design monitoring systems and they apply standard laboratory processes in quantifying the efficiency of their systems at producing algae and purifying the end products. Next students dive into the production of ethanol from cellulosic plant sources. They investigate the role of enzymes as well as different technologies used to produce ethanol and design an ethanol separation and purification system. In the last part of the unit students are challenged to apply their knowledge of biofuels, engineering design, and biomanufacturing practices as they develop a proposal for a commercial scale biofuels manufacturing plant.