What this work is about, in plain words
Is the surface of a photobioreactor evenly lit? The authors modelled the light distribution from LEDs, fluorescent and mercury lamps and showed how uneven it can be.
Articles on growing microalgae usually describe light briefly: lamp power, color and average irradiance. The spectrum of the source and the distribution of light across the surface remain in the background, although cell growth and biosynthesis depend on them. The authors set out to show how much these characteristics differ between common light sources.
Lighting simulation was used to calculate how light is distributed over the working surface of a photobioreactor when lit by LEDs, fluorescent lamps and powerful DRL mercury-vapor lamps. The spectra of similar-looking white light sources were compared separately.
According to the authors, irradiance differs substantially at different points of the surface. Because of this, cells being mixed move between light and shade, and such a regime is hard to describe. Sources whose light looks the same to the eye have different spectral compositions. For uniform lighting, the authors recommend LED strips and advise against point sources such as DRL lamps. They also give recommendations on how to describe light conditions in research.
The work helps to set up comparable experiments and to choose lighting for installations.
Limitations. This is computational modelling without testing on culture growth.