This Zero-Energy Building Uses Algae for Power and Shade

In a little over a month, a new German building will be the first in the world to have a "bioreactor facade" that can create energy, provide shade, and control light.

The walls facing the sun are lined with giant glass panels that act as microalgae farms: fed with water and sunlight, the tiny plants grow until they're big enough to be harvested and sent to a nearby biogas plant to generate energy.

The glass panels are also designed to capture the warmth of the sun to heat the building and provide hot water. Excess heat can even be stored in the ground as geothermal energy.

Since the algae grows fastest in the summer when the days are long and there's more sunlight, it can double as shade to help keep the building cool. It also helps insulate the building throughout the year.

Inside, the architects experimented with unique designs for two of the apartments; instead of having separate rooms, individual components—the bathroom, kitchen, and sleeping area—can actually be automatically reconfigured, to help residents switch between living and working spaces (sadly, no photos of this feature were available; it's an interesting concept).

The building will be featured in the International Building Exhibition (IBA) in Hamburg.

This month, challenge a neighbor to GOOD's energy smackdown. Find a neighbor with a household of roughly the same square footage and see who can trim their power bill the most. Throughout February, we'll share ideas and resources for shrinking your household carbon footprint, so join the conversation at good.is/energy.