Algae are believed to be a good source of renewable energy because of its rapid growth rate and its ability to be cultivated in waste water or waste land. Several companies and government agencies are making efforts to reduce capital cost and operating costs and make algae fuel production commercially viable. Algae are the fastest growing plant and theoretically have the potential to produce more oil or biomass per acre when compared to other crops and plants. However, the energy efficiency ratio and carbon and water footprint for algal based biofuels still need to be evaluated in order to fully understand the environmental impact of algal derived biofuels. 1. Introduction Even though algae have been studied for ~70 years, it is especially important now due to global warming, fluctuation in oil prices, and energy dependence on foreign nations. The first interest occurred during World War II, when these organisms were investigated as a potential source of a number of products such as antibiotics and a good source of protein [1]. In the late 1940s and early 1950s, the Carnegie Institution of Washington sponsored construction of a pilot plant and supplemental laboratory studies. This work is summarized in a report which serves as a valuable source of information even today for algae cultivation [1]. Commercial systems designed to produce algae for human consumption were developed in Japan in the 1960s [2]. The algal lipids would be an ideal feedstock for high energy density transportation fuels such as biodiesel, green jet fuel and green gasoline. Since it does not complete with food price, agricultural land and that it has the ability to sequester large quantities of carbon dioxide [3]. Biofuels are expected to be one of the major sources of renewable energy which mainly comprises of biodiesel, bioethanol, and biogas [4, 5]. Years of study indicate that various human activities such as deforestation and burning of fossil fuels have led to increase in the concentration of carbon dioxide in the atmosphere causing global warming. The burning of fossil derived transportation fuels significantly contributed towards greenhouse effect. The most rapidly growing sector is the transportation sector. Recent report from Environmental Protection Agency indicates [6] that 28% of worldwide greenhouse gas emissions comes from the transportation sector alone. Hence, the transportation sector has become an important target for the reduction of greenhouse gases. 1.1. The Concept of Production Biofuels from Microalgae The notion of producing biofuels from microalgae was
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