Multifunctional Light-Diffusing Fibers for Simultaneous Light Management and Fluid Transport in Microalgae Bioreactors

Recent research into the generation of food, feedstock, and biofuel using microalgae suggests that algae are orders of magnitude more efficient in the generation of usable biomass than higher crops. Systematic culturing of microalgae will therefore be one important component in a portfolio of strategies needed to ensure food and fuel security for a rapidly increasing world population. However, current efforts in culturing algae on an industrial scale are not yet economically viable. Major costs are associated with the energy needed for the actuation of large water masses in the culture volume to ensure adequate supply of light and carbon dioxide to the entire culture.

We aim to realize a novel class of multifunctional micro- and nanostructured optical fibers for light distribution management and carbon dioxide supply in industrial microalgae cultures. We propose to design, fabricate, and test multifunctional optical fibers with tailored axial and radial scattering profile and customized porous core-cladding morphologies, which will allow for controlled light and carbon dioxide transport thereby enabling homogeneous illumination levels and CO2 distribution in the algae culture volume.

This simple, energy-efficient means of ensuring homogeneous light distribution together with simultaneous delivery of carbon dioxide in dense, highly absorbing microalgae will help to achieve the full economic and social potential of algae cultures for food, feedstock, and biofuel generation. The proposed fiber technology will form a platform for bioreactor and open pond designs that allow for significantly more efficient management of light and nutrient supply in microalgae cultures without the need of energy-intensive culture actuation.