Is biodiesel from microalgae a real energy option? Preliminary Life Cycle Assessment of a multigeneration system (2nd RCN Conference on Pan American Biofuels..)

RODRIGUEZ, PAULA DANIELA; ARENA, ALEJANDRO PABLO; CIVIT, BÁRBARA; PIASTRELLINI, ROXANA

Nueva York

Conferencia; 2nd RCN Conference of Pan American Biofuels & Bioenergy Sustainability; 2016

Global predictions have indicated that the world population will need 50% more fuel, 50% more water and a 50-80% reduction in carbon dioxide (CO2) emissions by the year 2050. In this context, renewables energies will have an important role replacing fossil fuels, especially biofuels (biodiesel and bioethanol), since they can be used in transportation. Many authors have pointed out the microalgae as the major raw material for biofuels production, principally biodiesel. This is possible because the microalgae have higher productivities than crops, they can accumulate very large amounts of triacylglycerides (the major feedstockfor biodiesel production), they consume CO2 and they can grow in marginal land or wastewater. Nevertheless, it is facing numerous economic and technologic challenges that need to be solved before biodiesel becomes a real alternative to fossil fuels usage. Also, many energetic and environmental analysis exhibit very divergent results that put the sustainability of biodiesel into doubt. Consequently, the production of biodiesel from microalgae is an area that needs to be fully explored. The aim of this study is to evaluate the energy balance in the life cycle of a multigeneration system for production of biofuels andco-products through microalgae cultivation in compact tubular photobioreactors (PBR). For this purpose, the Life Cycle Assessment (LCA) based on the recommendations of the ISO 14040 is performedThe results show that the production of biodiesel from microalgae has large energy inputs; therefore, it is necessary to take into account the production of various co-products to enhance the environmental performance of the biodiesel. It seems that multigeneration strategies have potential to produce energy and multiple products from microalgae. Consequently, biodiesel from microalgae will become an alternative source of energy only if it is produced into multigeneration systems. This study also demonstrates the relevance of LCA toevaluate different scenarios into multigeneration systems and to indicate critic points in the biofuels production chain.