Biodiesel from Microalgae: Complementarity in a Fuel Development Strategy

Biodiesel produces fewer pollutants than petroleum diesel, and is virtually free of sulfur. These properties make biodiesel an attractive candidate to facilitate compliance with the Clean Air Act Amendments of 1990 (CAAA). This fuel is ordinarily considered to be derived from oilseeds, but an essentially identical biodiesel can be made from microalgae. This technology is complementary to ongoing efforts to grow lignocellulosic biomass in areas with good soil and water resources, because microalgae are projected to be grown in those areas where lignocellulosics or oilseed crops will not grow well (desert southwestern United States and other areas with poor soils). Another area where microalgae are complementary to other energy crops is in quad potential and market readiness. The potential contribution of oilseeds and waste fats to the energy supply is much less than I quadBTU/yr (l EJ*/yr). However, oilseed biodiesel can be made available quickly, thus helping to solve local air pollution problems over the short term and establishing an early market niche for biodiesel. Microalgal biodiesel would come on line later after further technology development to fulfill the multi-quad demand for diesel. Biodiesel Definition The esters derived from oils and fats from renewable biological sources are defined as biodiesel (Clements 1992). Typically, oils from microalgae, animal fats, and oilseed crops are chemically very similar, if not identical.