French biochemist Pierre Calleja has designed a fascinating eco-friendly lamp that could light up streets and parking garages while cutting CO2 emissions. It runs completely free of electricity, powered solely by a tube filled with glowing green algae. The lamp uses the energy created by the algae’s own photosynthesis process to power the light within, while the algae itself lives on CO2 in the air outside.

The lamp is designed so it can store the energy from photosynthesis for later use. That way, when it’s transported into low-light areas, it can glow without the need for any external power source. A single lamp could absorb roughly a ton of carbon from the air in just one year — the same amount as 150 or 200 trees. If these lamps could go into mass production, they could go a long way toward fighting climate change and reducing air pollution.

Interestingly enough, the lamp isn’t the only novel application Calleja has found for microalgae. He and his team at FermentAlg are already using microalgae for all kinds of applications, from a sustainable source of Omega 3 supplements to a base for natural cosmetics. They’ve even figured out how to harness algae as a source of biofuel.