3rd Generation Biofuels - Chapter 19, Biodiesel from microalgae

Many microalgae species have the potential to yield substantial quantities of lipids from production systems with small environmental footprints. However, commercial-scale developments face economic and technical hurdles. Advances in technology in recent years are slowly overcoming many of these hurdles. Genetic engineering of certain algal strains using the recently refined CRISPR-Cas9 technique has shown promise in stabilizing growth and improving the yield of lipids. Methods that succeed in one-step harvesting and lipid extraction from wet biomass offer ways of reducing production costs. The possibility to combine solar photovoltaics with high-rate algal ponds has been successfully tested and can be improved by filtering the incident light to concentrate the red bandwidth. Exploiting sources of wastewater and industrial effluent as nutrient supply can also improve plant yields and efficiency and reduce input costs. To minimize the cost of supply, it is necessary to develop plants that produce other high-value products in addition to biodiesel. Omega-3 polyunsaturated fatty acid, a widely used component in food, health supplement, and pharmaceutical industries, is one such co-product. Some nutrient-rich co-products also have markets as biofertilizers for land agriculture and fish/crustacean farming. A vision for a biodiesel-from-microalgae plant of the future is a biorefinery exploiting genetically modified algal strains, renewable (mainly solar) power sources, and wastewater/effluent treatment facilities for nutrient and water supply with a one-step harvesting/lipid process.