A novel experimental approach to achieve optical properties of algae panels improving visual-thermal comfort in office buildings

Abstract

This research paper explores how microalgae photobioreactor panels (PBR) impact daylight performance and visual comfort in office buildings. It merges experimental testing and computational simulation to investigate the effects of spirulina platensis microalgae in PBR panels on daylight measurements and glare potential. Most building-related simulations do not utilize the actual radiance properties of microalgae. The novelty of this research lies in highlighting a specific framework to obtain the most accurate optical properties in simulation techniques, including specular transmittance, specular reflectance, diffuse transmittance, and diffuse reflectance. Additionally, it addresses simulation troubleshooting and the lack of information in previous research while simplifying changes in algae concentration. This approach aims to achieve a numerical ratio of the daily increase in microalgae concentration and the decrease in transmitted light, thereby addressing an important gap. A state-of-the-art approach is developed to create a comprehensive framework for transferring all optical properties from experimental data to simulation, maximizing the accuracy of results and the performance of spirulina microalgae. Using a ratio of 1:60 microalgae to water, 85 % of the space is glare-free throughout the year. After one day of growth, maintaining a constant microalgae-to-water density on the second day results in 95.5 % of the space being glare-free throughout the year. Both occupants on the second day of algae cultivation achieve visual comfort, characterized by imperceptible glare, consistently throughout the year. Considering that the density of the highest daylight efficiency was obtained on the first and second days of spirulina microalgae cultivation and the amount of glare was compatible with the occupant's eyes on the first day, so visual comfort can be provided to the residents without reducing the daylight efficiency. The study finds that PBR panels can effectively control glare, but their influence on daylight availability should be maximized.