Optimizing Light Dispersion in a Microalgae Culture to Improve Growth for Environmental and Energy Applications

Abstract

The future of the environment will be defined by achieving sustainable energy production processes, combined with both air and water pollution mitigation strategies. The use of microalgae technologies has proven to be a potential option to many of these issues, however its implementation is not yet economically viable due to large costs of large-scale culturing. The work presented in this thesis serves two functions: 1. To look at ways to improve algal growth rates and cell densities in an effort to drive these technologies towards cost-effectiveness. 2. To set up a laboratory space for further research into the potential of microalgae, establishing procedures and gathering and assessing materials for further experimentation. Over the course of this research, I have cultivated nine different microalgal species and performed a number of experiments to advance the understanding of the effect of different light wavelengths on culture growth. Major conclusions include empirical growth curves for D. salina under different light conditions, and analysis of light penetration through an algae culture, leading to an improved growth technique of staging different light conditions with different growth phases of the algae. A final experiment tested the proof of concept of using the spectral shifting dye perylene red to enhance algae growth by absorbing non-photosynthetically active wavelengths, and re-emitting more usable energies. This was ultimately inconclusive, requiring improvements to the set up design.