Microalgae integrated into building facades

Biomimicry with another example today: the facades of buildings in microalgae which can allow us to produce gas, hot water or food supplements.

franceinfo: The use of microalgae on facades is already a reality in Germany, and in France the process is just beginning to see the light of day?

Anne-Laure Dagnet: In Paris, the Algo House is emerging from the ground in the 13th arrondissement of the capital. It’s a residential building that will have facades filled with microalgae, this gives large windows that are all green, or red or brown, depending on the algae grown.

It was an architectural firm that joined forces with CNRS researchers to develop the process: they made a photo bioreactor, a sort of ultra-flat vertical aquarium, powered by water and gas. carbon dioxide, to feed the algae. Phytoplankton develop there, wedged between two walls of glass. A heat exchanger is placed behind these somewhat special panes to regulate the temperature of the facades and capture the energy released by the microalgae.

These microalgae facades have several advantages?

Yes, microalgae produce biomass, energy that can be transformed into heating gas, this allows serious savings. They can also produce hot water, thanks to these facades which work a bit like thermal solar panels.

To live, these microscopic algae need carbon dioxide, CO2, they transform it into oxygen and biomass, this is photosynthesis. They are therefore able to absorb carbon emissions, a greenhouse gas, so they can help to slow down global warming a little.

And are there plenty of possible uses for this algae culture on building facades?

Yes, cultivating microalgae can be very profitable, in the cosmetics industry, a kilo of dried seaweed sells for gold! These phytoplanktons can also be used to make food supplements, there are plenty of them in organic shops, the seaweed is appreciated for its antioxidant qualities, it also provides vegetable proteins. The residues of these microalgae can also be used in construction by becoming an ingredient of bitumen, they could be used to build roads.