Optimization of the lighting system for a Hydraulically Integrated Serial Turbidostat Algal Reactor (HISTAR): Economic implications

• Published in: Aquacultural engineering Vol. 40; no. 1; pp. 45 - 53
• Main Authors: Benson, Barbara C., Gutierrez-Wing, Maria T., Rusch, Kelly A.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.01.2009; [Amsterdam]: Elsevier Science; Elsevier
• Subjects: Algae; Animal aquaculture; Animal productions; aquacultural and fisheries equipment; aquacultural engineering; aquatic plant culture; Biological and medical sciences; cost analysis; Economics; equipment design; Fundamental and applied biological sciences. Psychology; General aspects; HISTAR; lamps; Light dynamics; Microalgal culture; optimization; photosynthesis; Productivity model; simulation models; Microalgal culture; Economics; Productivity model; HISTAR; Light dynamics; Productivity; Algae; Optimization; Environmental engineering; Dynamics; Light; Models; Turbidostat; Culture; Aquaculture
• ISSN: 0144-8609; 1873-5614
• DOI: 10.1016/j.aquaeng.2008.11.001

An estimated 28% of the production cost in HISTAR systems that are artificially illuminated is attributed to the lighting cost. This cost estimated is based on an operational configuration comprised of eight CFSTRs, a system dilution rate (Ds) of 0.640d−1, and 400W metal halide lamps positioned at an elevation of 38.1cm over the culture. Deterministic model simulations of the volumetric productivity (Pv), photosynthetic efficiency (Eo) and lighting cost (LC) under various management strategies, operational parameters and reactor design configurations were performed and compared to the simulation results obtained for the original configuration. The simulations showed that LC may be reduced by 35.5% by switching from a metal halide (MH) to high-pressure sodium (HPS) light source at an optimum system dilution rate Ds=0.641d−1. LC may be reduced by an additional 17.8% through decreasing the lamp elevation to 25.4cm. Increasing the wattage of the light source from 400 to 1000W in the last six reactors would reduce the LC by 13% from the original cost. Overall, using HPS lamps at 25.4cm height, with six 1000W and two 400W lamps at a Ds=0.641d−1 will result in a 54% overall LC reduction compared to the original configuration of HISTAR. This represents a 13% reduction in the overall microalgal production cost for HISTAR.