National Algal Biofuels Technology Review Bioenergy Technologies Office June 2016 National Algal Biofuels Technology Review U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Bioenergy Technologies Office June 2016 Review Editors: Amanda Barry,1,5 Alexis Wolfe,2 Christine English,3,5 Colleen Ruddick,4 and Devinn Lambert5 2010 National Algal Biofuels Technology Roadmap: eere.energy.gov/bioenergy/pdfs/algal_biofuels_roadmap.pdf A complete list of roadmap and review contributors is available in the appendix. Suggested Citation for this Review: DOE (U.S. Department of Energy). 2016. National Algal Biofuels Technology Review. U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Bioenergy Technologies Office. Visit bioenergy.energy.gov for more information. 1 Los Alamos National Laboratory 2 Oak Ridge Institute for Science and Education 3 National Renewable Energy Laboratory 4 BCS, Incorporated 5 Bioenergy Technologies Office This report is being disseminated by the U.S. Department of Energy. As such, the document was prepared in compliance with Section 515 of the Treasury and General Government Appropriations Act for Fiscal Year 2001 (Public Law No. 106-554) and information quality guidelines issued by the Department of Energy. Further, this report could be “influential scientific information” as that term is defined in the Office of Management and Budget’s Information Quality Bulletin for Peer Review (Bulletin). This report has been peer reviewed pursuant to section II.2 of the Bulletin. Cover photo courtesy of Qualitas Health, Inc. BIOENERGY TECHNOLOGIES OFFICE Preface Thank you for your interest in the U.S. Department of Energy (DOE) Bioenergy Technologies Office’s (BETO’s) National Algal Biofuels Technology Review. This 2016 update to the 2010 National Algal Biofuels Technology Roadmap is a review of algal biofuels research at every step of the supply chain. It addresses several research areas highlighting advances, outlining unknowns, and discussing opportunities for advancement. Domestic renewable energy provides potential solutions to priorities for the United States, such as decreasing dependence on foreign oil, revitalizing rural America by creating new jobs across many sectors of the economy, and reducing carbon emissions. Through strategic investments and close coordination with partners in industry, academia, national laboratories, and other agencies, DOE is committed to developing and demonstrating transformative and revolutionary bioenergy technologies for a sustainable nation. Algae have significant potential to support an advanced biofuels industry. The goal of the BETO Advanced Algal Systems Program is to develop cost-effective algal biofuels production and logistics systems. The program focuses on supporting the growth of the emerging domestic algae industry and its interest in commercialization for fuels and products, specifically by reducing costs of production and ensuring the sustainability and availability of resources. DOE revived its investment in algal biofuels in 2009 in response to the increased urgency of lowering greenhouse gas emissions and producing affordable, reliable renewable energy, as well as the increasing recognition that we will not achieve these goals via any single technology pathway. Since then, BETO has invested in a variety of research, development, and demonstration (RD&D) projects that tackle the most impactful barriers associated with the scale- up of commercial algal biofuels. BETO is proud of the progress of our partners, and has the pleasure of highlighting many of their projects within this review, along with the work of the broader research community. The National Algal Biofuels Technology Review, as a summary of algal biofuels research and development to-date, serves as one reference to inform the implementation of the BETO strategy to achieve the vision of a thriving and sustainable bioeconomy fueled by innovative technologies. This review is intended to be a resource for researchers, engineers, and decision-makers by providing a summary of algal biofuel research progress to date and the challenges that could be addressed by future RD&D activities. We hope this review fosters and informs participation from all stakeholders as the next steps are taken to advancing an algal biofuels industry together. DOE looks forward to continuing its work with diverse partners in the development of renewable energy options that provide the greatest benefits in the years to come. Jonathan L. Male Director, Bioenergy Technologies Office U.S. Department of Energy Preface i FROM ALGAE TO BIOFUELS An Integrated Systems Approach to Renewable Energy that Is ALGAE FEEDSTOCKS CULTIVATION Microalgae and cyanobacteria can be cultivated via photoautotrophic methods (where algae require light to grow and create new biomass) in open or closed ponds or via heterotrophic methods (where algae are grown without light and are fed a carbon source, such as sugars, to generate new biomass). Macroalgae (or seaweed) has different cultivation needs that typically require open off-shore or coastal facilities. Designing an optimum cultivation system involves leveraging the biology of the algal strain used and inegrating it with the best suited downstream processing options. Choices made for the cultivation system are key to the affordability, scalability, and sustainability of algae to biofuel systems. Fermentation Tanks MICROALGAE CYANOBACTERIA MACROALGAE Closed Photobioreactors Algae as feedstocks for bioenergy refers to a diverse group of organisms that include microalgae, macroalgae (seaweed), and cyanobacteria (formerly called “blue-green algae”). Algae occur in a variety of natural aqueous and terrestial habitats ranging from freshwater, brackish waters, marine, and hyper-saline environments to soil and in symbiotic associations with other organisms. Understanding, managing, and taking advantage of the biology of algal strains selected for use in production systems is the foundation for processing feedstocks into fuels and products. Open Ponds Example Cultivation Systems POLICY SITING AND RESOURCES Systems and Techno-Economic Analysis: GuidingDevelopment the Research Path Towardand a Commercially Viable Algal Biofuel Industry FROM ALGAE TO BIOFUELS An Integrated Systems Approach to Renewable Energy that Is Abundant, Affordable, and Sustainable HARVESTING / DEWATERING CONVERSION Some processes for the conversion of algae to liquid Conversion to fuels and products is predicated on a basic transportation fuels require pre-processing steps such as process decision point: harvesting and dewatering. Algal cultures are mainly grown 1) Conversion of whole algal biomass; in water and can require process steps to concentrate 2) Extraction of algal metabolites; or harvested algal biomass prior to extraction and conversion. 3) Processing of direct algal secretions. These steps can be energy-intensive and can entail siting Conversion technology options include chemical, issues. biochemical, and thermochemical processes, or a CH2-O-C EXTRACTION combination of these approaches. The end products vary depending on the conversion technology utilized. Focusing on biofuels as the end-product O poses challenges due to the high volumes and relative low CH -O-C R 2 1 values associated with bulk commodities like gasoline and O diesel fuels. CH-O-C R2 O CH2-O-C R3 Bio-Crude Algal Lipid: Precursor to Biofuels Three major components can be extracted from algal biomass: lipids (including triglycerides and fatty acids), carbohydrates, and proteins. Most challenges in extraction are associated with the industrial scale up of integrated extraction systems. While many analytical techniques exist, optimizing extraction systems that consume less energy than contained in the algal products is a challenge due to the high energy needs associated with both handling and drying algal biomass as well as separating out desirable products. Some algal biomass production processes are investigating options to bypass extraction, though these are also subject to a number of unique scale-up challenges. End Uses: • Biodiesel • Biogas • Renewable Hydrocarbons • Co-products • Alcohols (e.g., animal feed, fertilizers, industrial enzymes, bioplastics, and surfactants) REGULATIONS AND STANDARDS Systems and Techno-Economic Analysis: GuidingDevelopment the Research Path Towardand a Commercially Viable Algal Biofuel Industry BIOENERGY TECHNOLOGIES OFFICE Contents 1. Overview of Algal Biofuels and Work from the U.S. Deparment of Energy ...........................1 1.1 History of the Review .............................................................................................................................................1 1.2 America’s Energy Challenges ............................................................................................................................1 Algal Feedstocks .....................................................................................................................................................2 1.3 A History of Domestic Algal Biofuels Development ...............................................................................3 Early Work to 1996 .................................................................................................................................................3 Research from 1996 to 2008 ..............................................................................................................................6 Algae Program Research