Free Light, Fresh Air: The Promise of French Algae Lamps

by Kids Discover

Pierre Calleja inspects a prototype street lamp in his laboratory in LibourneOkay, here’s a riddle: What kind of lamp creates its own electricity, converts carbon dioxide (CO2) into oxygen, has no on/off switch, and works 24 hours a day?

An algae lamp, of course! While you won’t find these at your local lighting store anytime soon, the groundbreaking algae lamps invented by French biochemist Pierre Calleja have the potential to help purify our atmosphere and save enormous amounts of electricity … by creating their own.

Here’s how they work: The lamps are basically big clear tanks filled with water, algae, a light, and a chargeable battery. Certain kinds of algae — Calleja says they’re among “man’s best friends” — can feed off the sun’s energy and/or organic carbon.

Inside the lamp, the algae break down CO2 into oxygen molecules and carbohydrate energy. They use that energy to create power, which is stored in the battery and can fuel the light even when the sun isn’t out. So the light is free, and even better — the oxygen produced by the algae returns to the atmosphere.

Here’s why that’s important: CO2, a very common byproduct of human activity, is one of the greenhouse gases that contributes to climate change. Trees and other plants convert CO2 into oxygen and energy, but as humans turn green areas like forests into areas for buildings, agriculture, and mines, we lose the trees and their oxygenating effects, which accelerates the so-called greenhouse effect of atmospheric warming.

A microbiologist for 20 years, Calleja says that one of his lamps, recently installed in an underground parking garage in Bordeaux, France, can capture and filter literally a ton of CO2 a year. This lamp represents the beginning of his dream: He’d like to see his algae lamps installed not just in garages, but also in homes and along roads, where they could purify the exhaust straight from cars’ tailpipes.


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