Full Title: The Energy Return on Investment for Algal Biocrude: Results for a Research Production Facility
Author: Colin M. Beal, Robert E. Hebner, Michael E. Webber, Rodney S. Ruoff, and A. Frank Seibert
Publisher(s): University of Texas at Austin
Publication Date: 07/2011


Description (excerpt):

This study is an experimental determination of the energy return on investment (EROI) for algal biocrude production at a research facility at the University of Texas at Austin (UT). During the period of this assessment, algae were grown at several cultivation scales and processed using centrifugation for harvesting, electromechanical cell lysing, and a microporous hollow fiber membrane contactor for lipid separation. The separated algal lipids represent a biocrude product that could be refined into fuel and the post-extraction biomass could be converted to methane. To determine the EROI, a second-order analysis was con- ducted, which includes direct and indirect energy flows, but does not include energy expenses associated with capital investments. The EROI for the production process evalu- ated here was significantly less than 1, however, the majority of the energy consumption resulted from non- optimized growth conditions. While the experimental results do not represent an expected typical case EROI for algal fuels, the approach and end-to-end experimental determination of the different inputs and outputs provides a useful outline of the important parameters to consider in such an analysis.