Eco-friendly 'algae curtains' could help curb air pollution in crowded cities

Air pollution is an enormous problem in many urban areas, but two European architects have developed plant-filled plastic curtains designed to turn building facades into “living walls” that help purify dirty air.

The curtains contain a mazelike network of tubes filled with microscopic algae, which like all green plants remove carbon dioxide from the air while pumping out oxygen via the carbon-sequestering process known as photosynthesis. Air flows into the bottom of the curtains and rises through the tubes, feeding the microalgae along the way.