This green urban furniture is standing tall at a sidewalk of a crossroad connecting avenue Général Leclerc and Rue d’Alésia, where more than 72 000 cars pass every day. The column style isn’t new for Parisians. It resembles the Morris column, used as an ad platform since the 19th century. But this one has another role. It is meant to improve air quality in the French capital.
Inside this huge column, there is an aquarium with microalgae that transform the carbon dioxide (CO2) from the air into oxygen. It may sound futuristic – and it is. But this pilot project relies on a two-billion-year technology: photosynthesis.
“This device reproduces and amplifies the effects of a forest”, said Célia Blauel, responsible for the environment and sustainable development for the city of Paris, according to Le Parisien.
Turning air pollution into clean energy
This column has the capacity to remove from the air and store 1 ton of CO2 per year, or the equivalent capacity of 100 trees, according to the project designers. It was developed by the French company Suez, expert in the water and waste sectors, who proposed to Paris city hall to test the experiment in avant-première. The innovative project also has the ambition of transforming air pollution into clean energy. How come?
By absorbing CO2, the micro algae will grow and reproduce. Once the population increases to a certain level, those CO2-eaters will be released into the sewage network. Then the microalgae will reach the near sewage treatment plant where they will be transformed into biogas or biomethane to heat houses in the Winter.
The idea sounds promising since the microalgae have the advantage of growing anywhere, including urban highly polluted areas. If this experiment succeeds, we will probably have more columns alike across cities. So far, Suez has not communicated their cost, according to Le Monde. Results are yet to be assessed, as the column is active since the beginning of this Summer.
The capacity of such green pipe to absorb CO2 is small if compared to the capacity of forests and oceans to clean the air. They absorb half of the human carbon emissions and produce the Earth’s oxygen. But considering the threat upon those ecosystems and the scale of the climate change, innovative solutions are welcome. We can only hope this experiment will help us to breathe a cleaner air.