Microalgae culture as feedstock for biofuels

World population and energy consumption per capita are increasing every year; they are expected to double from 2000 to 2050. This energetic demand cannot be satisfied entirely by fossil oil. Renewable energies are needed for petroleum replacement, because fossil energetics contribute to global warming and are of limited availability. In recent years, technologies for renewable energy have been developed and implemented, such as wind, solar, hydropower, geothermal or biomass. The power sector can be supplied with these renewable sources, nevertheless, the transportation sector, which represents 28% of global energy consumption, strongly depends on renewable liquid fuels. Biodiesel and bioethanol are the two potential renewable fuels that have been considered as fossil fuels substitutes. Presently, biofuels are produced from common sugar and starch crops (bioethanol) and vegetable oils or animal fats (biodiesel). This feedstock production in large quantities is not sustainable. Microalgae, photosynthetic microorganisms that convert sunlight, water and carbon dioxide to biomass, represent a remarkable alternative to produce biofuels. The algal cultures have several advantages over plants, the grow extremely rapidly and many of them show high oil yields and productivities, algae does not compete with food or feed crops or farmland; they do not have high requirements for nutrients or water, algal cultures benefit small scale farmers and energy security, and contribute to mitigate climate change. In this chapter, an overview of biofuels production from algae is given, emphasizing on the production of algal biomass as raw material. In addition, it presents part of the research that is being performed in the Professional Interdisciplinary Unit of Biotechnology, National Polytechnical Institute (IPN, for its initials in Spanish). Research focuses mainly on the development of algal biofuel technologies. Some results on the obtained algal strains and improvement of culture media are also presented.