Photobioenergy

Using photosynthetic microorganisms to convert sunlight and CO2 directly into sustainable fuels and products

Photosynthetic microorganisms capture sunlight energy and use it to fix CO2 into organic molecules.  Our PhotoBioReactor (PBR) Team focuses on means to grow and manage phototrophic microorganisms that produce organic products that are renewable and carbon neutral substitutes for materials that mainly come from fossil sources today.  Sometimes the high-value compounds are part of the microorganisms themselves.  An excellent example is the lipids in membranes and storage products inside the cells.  In this case, we harvest the biomass and extract the high-value materials.  In other cases, we modify the microorganisms to produce and excrete organic molecules that we harvest and directly convert to fuels or chemicals.  Great examples are lauric acid, which can be converted to jet fuel, and isoprene, which can be turned into a lubricant.  We call this second approach the “photosynthetic factory,” since the microorganisms act as tiny sun-driven factories that export renewable products for us to harvest.

The PBR Team’s research carries out fundamental-to-applied research in these inter-related areas:  advanced PBR designs to maximize the harvest rate of the product while minimizing the rates of water and nutrient use; mathematical modeling to connect all the microbiological, chemical, and transport processes occurring in the PBR; understanding and managing the microbial communities that develop in PBRs; and developing a wide range of high-value products.  The Team conducts its cross-disciplinary research in the laboratory and with its unique outdoor test beds.

One of the current focus of the PBR team is the Atmospheric CO2 Capture, Enrichment and Delivery (or ACED) project, which is supported by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy Targeted Algal Biofuels and Bioproducts program under Award Number DE-EE000709.  One of the main challenges in the microalgae area is that CO2 levels in the environment still limit the growth of microalgae.  In this project, in collaboration with Dr. Klaus Lackner, we will use anionic resins to reversibly bind atmospheric CO2 and deliver concentrated CO2 gas streams to the microalgae through membranes with nearly 100% efficiency to significantly improve the microalgae growth rates. If successful, this project could significantly lower the cost of producing fuels and products using microalgae and allow producing commodity products, such as fuels, at the scales necessary to meet demand.  Read more about the project here.