Bioreactors can be used for cultivating macroalgae biomass for carbon fixation and the production of plant-based protein and typically consist of clear-wall containers or pipes through which a liquid medium in which algae grow is circulated.
The liquid medium is exposed to heat and light which cause the algae to multiply, after which the algae are removed by filtration for further processing. The efficiency of the growth process is defined by the amount of energy required in terms of heat and light input to achieve a certain algae biomass.
In this project, CultinovaEDGE™ hardware was utilised to improve the energy efficiency of bioreactors for algae production by optimising incident light spectral intensity through the use of supplementary LED lighting.
To further increase the efficiency of the system, a novel heat recovery system was developed where waste heat energy from the supplementary LED lighting was used to maintain the temperature of the liquid medium at its optimum value, effectively replacing a heater that would be normally used for this purpose.
The utilised small-scale bioreactor showed a 12% increase in algae biomass production for a 16% reduction in energy use, compared to a standard system, demonstrating the potential of this approach for energy and cost savings in large-scale commercial bioreactors for algae production.
