A Multi-Faceted Approach Supported by Incredible Facilities
USU's capabilities in biofuels research are underpinned by a 5 year, $6.5 million grant from the State of Utah. The Utah Science Technology and Research initiative (USTAR) is a long-term, state-funded investment ensuring Utah remains a leader in the knowledge-based economy. USTAR provided funds to recruit all-star researchers to Utah State University within strategically targeted innovation areas including algal-based biofuels.
USU is also progressing on an ongoing DARPA project (P-701-104266) teamed with Oak Ridge National Laboratory aimed at dramatically increasing algal biomass production rates in closed-system photo-bioreactors through improved sunlight utilization. The breakthrough research is based on low-cost sunlight collection and optimized light distribution systems applicable to both continuous flow and batch systems. The objective of the seedling project is to show that more efficient and intelligent sunlight distribution within photo-bioreactors can increase the growth rate of algal biomass by as much as a factor of 10 over existing photo-bioreactor systems while simultaneously demonstrating the ability to separate and use other portions of the solar spectrum constructively for other purposes such as electricity generation.
As a part of the project, USU has developed an improved, proprietary bioreactor design that bridges the gap between low-cost passive and sophisticated/costly two-axis tracking fiber-optic systems. Several features of the new design make it an attractive high-risk, high-payoff alternative to other open / hybrid / closed reactors. First, it incorporates methods to very efficiently deliver direct sunlight over a 10-to-20X larger surface area, increase yield, eliminate photosynthetic saturation and minimize surface shading. Second, it incorporates methods to simultaneously co-produce electricity with the otherwise wasted IR radiation. Third, it incorporates simple waveguide technology capable of uniformly redistributing focused sunlight using a proprietary low-cost process. Fourth, the low-profile design leverages experience gained by others related to well-established reactor technology.
"Several features of the new design make it an attractive high-risk, high-payoff alternative to other open / hybrid / closed reactors. First, it incorporates methods to very efficiently deliver direct sunlight over a 10-to-20X larger surface area, increase yield, eliminate photosynthetic saturation and minimize surface shading."
– Dr. Foster Agblevor
In a more general sense, the economic viability of commercial algae systems are extremely sensitive to yield, therefore maximizing yield is a critical objective. In algal growth, one of the most important factors to maximizing yield is providing algal biomass satisfactory light. This can be accomplished by introducing a variety of techniques to improve the surface area of algal medium exposed to light and optimizing light penetration. Utah State University (USU) has substantive experience in analyzing lighting conditions in photobioreactors. It is developing a combination of experimental and analytical tools to model lighting conditions within reactors of various configurations. Light penetration in algal reactors is a nonlinear process with attenuation resulting from both scattering and absorption. USU has modeled and experimentally-validated this phenomenon and is now in the process of integrating the results into ray-tracing software. In addition to this work, USU is also characterizing the spectral response of various high oil producing algae to better understand the affects of various wavelengths of light on algal growth and lipid accumulation. It has also developed fiber optic methods of measuring photosynthetically-active radiation at different depths within growth chambers. These skills will be especially valuable to private entities by offering a means of supporting enhanced lighting conditions in both the closed and open designs being considered.
USU has also accumulated extensive knowledge related to growth rates and lipid accumulation in several strains of algae. This knowledge and expertise can be integrated with other organizations doing synergistic work in the process of down-selecting to preferred algae strains to take forward to commercial-scale production.