There is a building in Hamburg, Germany, which is entirely powered by algae. Inside the glass panels is a green liquid in which you can see little bubbles rising to the surface. This is the result of having a bio-reactor built into the facade, which heats the 15 flats in the building. The motor is micro algae, and the principle is photosynthesis.
The building therefore effectively heats itself. The balcony looks like an aquarium with all the algae growing there. Also, this is a “passive building” meaning that it maintains a comfortable interior temperature without heating, which also means it saves money.
To get ready for the winter, the building makes underground stores of the heat produced during the summer, which it can then use several months later.
But it isn’t just heating. The project is also designed so that dead algae can be collected and used to make a food supplement which is rich in minerals.