| Description |
<br/> <br/> <br/> <br/> Background <br/> Energy <br/> Currently, the world consumes ~15 terawatts of energy per year and only 7.8% of this is derived from<br/>renewable energy sources. Yet, ~85,000 terawatts of sunlight hits the surface of the Earth every year<br/>(Cho, 2011). Despite this bounty of available renewable energy, replacing fossil fuel‐derived energy with<br/>renewable energy sources derived from sunlight, such as wind, solar, hydro, or biomass energy is a<br/>challenging in large part because these energy sources have a lower energy density, cannot be<br/>controlled with an ‘on and off’ switch, and most are currently considerably more expensive than what<br/>fossil fuels are today (Kerr 2011). <br/> Photosynthetic organisms such as higher plants, algae, and cyanobacteria use sunlight and carbon<br/>dioxide to produce a variety of commercially useful organic molecules, particularly proteins and lipids.<br/>Microalgae have a much faster growth rate than terrestrial crops, with many species doubling daily, and<br/>thus can be harvested accordingly. Furthermore, microalgae can grow in areas uninhabitable to other<br/>terrestrial crops, and thus do not displace these crops in the consumer food chain. The Department of<br/>Energy has identified Texas as an ideal location for large scale microalgal growth and commercialization<br/>of algal products, although a consistent supply of water remains a technical barrier to large scale<br/>growth. <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> Animal Feed <br/> The world’s current growth rate is at 1.2% and is projected to nearly double in 56 years from<br/>approximately 6.9 billion to 13 billion (PRB, 2008). With a rising human population, the availability of<br/>food resources is at serious odds with its growing demand. Of particular importance are sources of<br/>protein. In animal diets, soybean meal is the most widespread source of high‐quality protein<br/>incorporated to meet animal protein nutrient requirements as determined by the National Resource<br/>Council. Soybean meal may provide 44‐86% crude protein and is also responsible for a significant<br/>percentage of the feed costs (NRC, 1998). <br/> According to the Food and Agriculture Organization, there are 1 billion cattle, 40 billion poultry, 1 billion<br/>swine, and 2 billion sheep and goat populations globally (Steinfeld et al., 2006). Since soybean meal is<br/>also a staple food for human consumption, its strong prevalence as a protein source in animal diets<br/>directly competes with its application in the human food market. When considering the world food crisis<br/>and our growing population, it is evident that our current infrastructure of animal feed and human food<br/>sources is unsustainable. Thus, developing alternatives to using soybean meal in animal feed not only<br/>demands our immediate attention, but also is a necessary path for the sustainable livelihood of persons<br/>living on earth. <br/> The diversity of microalgae’s relatively rich amino acid profiles and high mineral composition make them<br/>a promising candidate for incorporation into animal feed. In a study on the nutrient composition of<br/>Spirulina maxima, over 60% of the dried alga was composed of crude protein, which consisted of all the<br/>essential amino acids. The algae supplement was also high in several vitamins, including B1, B2, and<br/>especially β‐carotene (pro‐vitamin A), and had adequate digestibility when fed to animals (Boeckaert<br/>2008; Herber 1996). As such, the concept of using microalgae as an alternative source of protein<br/>supplementation in animal feed presents an extremely exciting opportunity to improve global food<br/>security by increasing soybean meal availability for human consumption and fill a vital need for the<br/>future. <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> OpenAlgae Technologies <br/> Algae biomass and biofuels are not without limitations, largely due to the high cost of the infrastructure<br/>and the energy required for growth and harvesting due mainly to the high water content of growing<br/>algae. The traditional approach for harvesting and processing microalgae typically includes an algae<br/>concentration step, a drying step, and an extraction step. Concentration (dewatering) can be<br/>accomplished using a centrifuge, dissolved air floatation, or flocculation; algae can be dried using an<br/>oven or drum dryer; hexane or supercritical CO2 are typically used to extract algal oils. Not only are<br/>these processes expensive, but direct contact with hexane corrupts the biomass. Thus, using the<br/>traditional methods of processing algae, the grower may either monetize the oil or the feed, not both. <br/> <br/> The University of Texas recognized that in order for large scale algal growth to be successful, the grower<br/>must be able to recover algal oil products and monetize the clean biomass as feed or fertilizer. In 2007,<br/>UT formed a multidisciplinary team to develop technologies to drive down the cost of processing<br/>microalgae. Over the last four years, UT civil engineers have developed a flow‐through dewatering and<br/>concentration technique initially based on wastewater treatment strategies; electrical and mechanical<br/>engineers along with biochemists and physicists developed a technique to rupture algal cells and<br/>liberate algal oils; and chemical engineers repurposed off‐the‐shelf technologies to recover the liberated<br/>oils. All of these technologies have been assembled sequentially onto a mobile unit that can be driven to<br/>the grower’s site to harvest and process algae on a flow‐through basis from a pond or bioreactor to<br/>produce two products, bio‐oil and clean biomass. The system is appropriate for freshwater to seawater<br/>algae and the oil recovered from a site is dependent on the oil concentration within the algae. <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> Proposal <br/> We propose to assess various microalgae located on the San Domingo Ranch and perform a cost analysis<br/>for processing microalgae from this location using OpenAlgae technologies. A small team of UT<br/>researchers will sample microalgae from the site along with the associated water. Once the water<br/>chemistry is determined, the algae will be scaled up at the UT Algae Institute, then further evaluated for<br/>nutrient content, including proteins, carbohydrates, and lipids. Based on the growth inputs and nutrient<br/>contents, we will conduct an analysis of the costs associated with scaling up the selected algae at the<br/>site and compare these costs to projected revenues. Because microalgae availability varies throughout<br/>the year, algae will be sampled quarterly over the course of one year. Analyses will be performed as<br/>samples are collected and the information may be shared with the Dougherty Foundation as periodic<br/>reports. <br/> Specific Aims <br/> Aim 1: Identify local algal species with high protein and/or lipid concentration. UT will isolate algal<br/>species growing in moist environments in southeastern Texas. The alga may be growing in water or wet<br/>soil. A water chemistry analysis will be performed for each site to determine native growing conditions.<br/>The isolate will then be further grown at UT in the native water to a cellular density that will facilitate<br/>further analysis. The analyses will include, but may not be limited to, protein and lipid concentration. <br/> Aim 2: Conduct a Return on Investment (ROI) analysis based on the findings of Aim 1. The protein and<br/>lipid contents of the candidate algal species identified in Aim 1 will used to calculate the 1) volume of<br/>water required for scale‐up growth, 2) nutrients required for scale‐up growth, 3) the estimated cost of<br/>growth and processing of the algae, and 4) the estimated volume of algal oil or protein production at<br/>scale. These costs will be based on utilizing OpenAlgae processing technologies developed by the<br/>University of Texas. <br/> <br/> <br/> <br/> <br/> <br/> Deliverables <br/> Updates on selected algal species’ nutrient content and growth kinetics.<br/>Cost analysis of scale‐up and processing vs projected revenue. <br/>Final report detailing all findings and analyses. <br/> <br/> |
