Small elevated experimental raceways have been used at many research sites in the United States to evaluate algal biomass productivity. This paper evaluates whether the productivities measured in these raceways are representative of large-scale commercial raceways. Open water surface evaporation and temperature models with shading algorithms were programmed in Python programming language and calibrated with temperature and evaporation data from the elevated experimental paddlewheel raceways in the Regional Algal Feedstock Testbed (RAFT) experiments at the University of Arizona. The final calibrated model for elevated experimental raceways was named the EERTEM (Elevated Experimental Raceway Temperature and Evaporation Model). The energy balance algorithms in the Biomass Assessment Tool (BAT) were added to the Python code and used to simulate temperature in standard commercial paddlewheel raceways. A comparison of BAT and EERTEM simulations indicated that elevated paddlewheel raceway temperature fluctuations are not representative of in ground commercial paddlewheel raceways, primarily due to the buffering effect of soil heat flux. The Huesemann Algae Biomass Growth (HABG) model simulated biomass productivities of three algae species with the BAT and EERTEM temperature profiles for the commercial and elevated experimental raceways, respectively. Differences in productivity were observed when the maximum daytime temperature of one raceway was in the optimal growth range but the temperature of the other raceway exceeded or was below the optimal growth range. If both raceway temperatures were in the optimal growth range for a given species, even if they had different temperatures, then there was minimal difference in growth. In summary, the EERTEM is not an accurate representation of commercial raceway productivity.
Khawam, George, et al. "Model of temperature, evaporation, and productivity in elevated experimental algae raceways and comparison with commercial raceways."Algal Research,vol. 39,no. C, May. 2019. https://doi.org/10.1016/j.algal.2019.101448Khawam, George, Waller, Peter, Gao, Song, Edmundson, Scott, Wigmosta, Mark, & Ogden, Kimberly (2019). Model of temperature, evaporation, and productivity in elevated experimental algae raceways and comparison with commercial raceways.Algal Research,39(C). https://doi.org/10.1016/j.algal.2019.101448Khawam, George, Waller, Peter, Gao, Song, et al., "Model of temperature, evaporation, and productivity in elevated experimental algae raceways and comparison with commercial raceways,"Algal Research 39, no. C (2019), https://doi.org/10.1016/j.algal.2019.101448@article{osti_1581776, author = {Khawam, George and Waller, Peter and Gao, Song and Edmundson, Scott and Wigmosta, Mark and Ogden, Kimberly}, title = {Model of temperature, evaporation, and productivity in elevated experimental algae raceways and comparison with commercial raceways}, annote = {Small elevated experimental raceways have been used at many research sites in the United States to evaluate algal biomass productivity. This paper evaluates whether the productivities measured in these raceways are representative of large-scale commercial raceways. Open water surface evaporation and temperature models with shading algorithms were programmed in Python programming language and calibrated with temperature and evaporation data from the elevated experimental paddlewheel raceways in the Regional Algal Feedstock Testbed (RAFT) experiments at the University of Arizona. The final calibrated model for elevated experimental raceways was named the EERTEM (Elevated Experimental Raceway Temperature and Evaporation Model). The energy balance algorithms in the Biomass Assessment Tool (BAT) were added to the Python code and used to simulate temperature in standard commercial paddlewheel raceways. A comparison of BAT and EERTEM simulations indicated that elevated paddlewheel raceway temperature fluctuations are not representative of in ground commercial paddlewheel raceways, primarily due to the buffering effect of soil heat flux. The Huesemann Algae Biomass Growth (HABG) model simulated biomass productivities of three algae species with the BAT and EERTEM temperature profiles for the commercial and elevated experimental raceways, respectively. Differences in productivity were observed when the maximum daytime temperature of one raceway was in the optimal growth range but the temperature of the other raceway exceeded or was below the optimal growth range. If both raceway temperatures were in the optimal growth range for a given species, even if they had different temperatures, then there was minimal difference in growth. In summary, the EERTEM is not an accurate representation of commercial raceway productivity.}, doi = {10.1016/j.algal.2019.101448}, url = {https://www.osti.gov/biblio/1581776}, journal = {Algal Research}, issn = {ISSN 2211-9264}, number = {C}, volume = {39}, place = {United States}, publisher = {Elsevier}, year = {2019}, month = {05}}You mustSign In orCreate an Account in order to save documents to your library.