Algae may still be years away as a source for road and jet fuel. But could it power whole buildings before long?
If you think that’s crazy, then look at this recently completed five-story residential building in Hamburg. It is covered by panels filled with algae, a fast-growing form of biomass. The building pumps water, nutrients, and compressed CO2 between 129 "bioreactors." When the sun shines, the algae multiplies as a result of photosynthesis. The system collects the residue, then converts it to biogas, which is burned in a boiler. Together with a heat recovery system and solar panels on the roof, the building is completely energy independent, according to its creators.
The panels are 98 inches by 28 inches, 0.78 inches thick, and cover about 2,150 square feet, on two south-facing sides. Known as the BIK, the building, which has 15 apartments, is an entry to the International Building Exhibition and was completed last month. It will open to the public soon.
"Algae will be cultivated for the generation of energy but also to control the light inflow and shading of the building. The facade will be constantly in motion and changing its color," says exhibition spokesperson Anna Vietinghoff. "Production of regenerative energy will not take place in an invisible energy center but will be an explicit component of the architectural concept."
"It might well become a sustainable solution for energy production in urban areas, so it is great to see it being tested in a real-life scenario," says Jan Wurm, Arup’s European research leader, in a press release.
The companies haven’t said how well the building will perform in winter (algae doesn’t grow without light) or how much it might cost. But, encouragingly, they do say it’s safe to get rid of the wastewater via the sewer. Potentially, the concept could power whole buildings with low running costs and act as a CO2-sink at the same time. If so, that’s a pretty good combination.