An anonymous reader writes "Biochemist Pierre Calleja has a solution to reducing carbon emissions that doesn't require us to cut back on our use of carbon-producing devices. Calleja has developed a lighting system that requires no electricity for power. Instead it draws CO2 from the atmosphere and uses it to produce light as well as oxygen as a byproduct. The key ingredient to this eco-friendly light? Algae. Certain types of algae can feed off of organic carbon as well as sunlight, and in the process produce carbohydrate energy for themselves as well as oxygen as a waste product. Cajella's lamps consist of algae-filled water along with a light and battery system. During the day the algae produce energy from sunlight that is then stored in the batteries. Then at night the energy is used to power the light. However, as the algae can also produce energy from carbon, sunlight isn't required for the process to work. That means such lights can be placed where there is no natural light and the air will effectively be cleaned on a daily basis."