ES2009-90235 Assessing the Potential for Algal Biofuels Production in Texas ES2009-90235

Abstract

Abstract This paper describes a unique analytical model created to assess the maximum potential for algae production in Texas. The model, which merges engineering, biology and geosciences into a singular analysis, aims to identify suitable growth locations and estimate the quantity of algae-based oils that can be potentially produced in Texas. The model incorporates geographically-and temporally-resolved data on sunlight, anthropogenic CO 2 emissions, and saline or brackish water availability. These data are then overlaid with first-order biological approximations for algae growth calculations in order to create maps of algae growth potential. Solar insolation data were obtained from measurement locations throughout the state for varying time scales spanning many years from the Texas Solar Radiation Database (TSRDB). CO 2 emissions were compiled from area and point sources (such as natural gas and coal-fired power plants) from the Energy Information Administration and Environmental Protection Agency. Water data for wastewater treatment plants and saline aquifers were obtained from the Texas Commission on Environmental Quality and the Texas Water Development Board. A home-built MATLAB code uses these data, along with engineering approximations and the ability to manipulate different assumptions to calculate algae growth by location and time period. For each location, the model calculates potential oil yield, biomass produced, growth rates, water and CO 2 consumed and land used. Standard pond and tubular photobioreactor dimensions have been used to model real world production facilities. Realistic limits for growth rates, photosynthetic efficiencies, photosynthetic flux tolerances and oil content are also incorporated. These parameters can be varied to approximate different algae strains and growth conditions. The model assumes reactors to have ideal mixing, optimal pH and temperature controls in place