As reported in Scienceblog, the study, which is the first to analyse real-world data from an existing algae-to-energy demonstration scale farm, shows that the environmental and energy benefits of algae biofuel are at least on par, and likely better, than first generation biofuels.
The study, “Pilot-scale data provide enhanced estimates of the life cycle energy and emissions profile of algae biofuels produced via hydrothermal liquefaction (HTL),” is a life cycle analysis of an algae cultivation and fuel production process currently employed at pre-commercial scales. The authors examined field data from two facilities operated by Sapphire Energy in Las Cruces and Columbus, New Mexico that grow and process algae into Green Crude oil. Sapphire Energy’s Green Crude can be refined into drop-in fuels such as gasoline, diesel and jet fuel.
The study concluded that algae technologies at commercial scale are projected to produce biofuels with lower greenhouse gas emissions and EROI values that are comparable to first generation biofuels. Additionally, algae based biofuels produced through this pathway at commercial scale will have a significant energy return on investment (EROI), close to petroleum and three times higher than cellulosic ethanol. The system that was evaluated recycles nutrients, can accept an algae feed that is up to 90 per cent water in the processing phase, and the final product can be blended with refinery intermediates for refining into finished gasoline or diesel product, resulting in significant energy savings throughout the process.