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A challenge for alternative energy has been the development of a liquid alternative to petroleum, which dominates the countrys transportation sector. One feedstock that has potential in biodiesel production is microalgae, eukaryotic oxygenic photosynthetic microorganisms. With some species containing lipid contents as high as 70% of the cells biomass, microalgae could potentially produce over 15,000 gal/acre of biodiesel per year in a raceway system as compared to soybean which is capable of only 47 gal/acre per year. However, it has been noted that many microalgae predictions tend to be vastly overestimated. Variations in location, technique, and species will impact algal production and the extraction of lipids. Limited algal production will then require greater energy usage to accommodate the lack of oils produced. Given the relatively low biomass concentration obtainable in microalgal cultivation systems and the small size of microalgal cells, costs and energy consumption for biomass harvesting are significant concerns that need to be addressed properly. Using centrifugation, the authors determined that at higher flow rates, the lower capture efficiencies were offset by the larger volumes of culture processed and lower energy consumption. Energy consumption was reduced by 82% when harvesting was reduced to 28.5% efficacy. Culturing algal species with high lipid content and culture density could see harvesting costs drop to $0.864/L oil using centrifugation as the sole harvesting method. Applying this technique to other harvesting strategies could provide drastic improvements to overall costs.