|BIQ House at Hamburg’s International Building Exhibition|
News about the power surplus may not sound particularly like a win for green, until one pauses to think that it is occurring at the same time as Germany winds back the use of nuclear power, which might have been expected to result in a shrinking generation capacity. Actually, it has spurred a spectacular growth in renewables, both wind and solar photovoltaics. Current surplus power is sold to neighbouring countries, but clearly it also affords Germany the luxury of further lowering its dependence on fossil fuels.
One example of the remarkable effort Germany is putting in to explore and implement renewables comes again from Hamburg’s International Building Exhibition. Engineering firm Arup worked with Germany’s SSC Strategic Science Consultants and Austria-based Splitterwerk Architects to develop BIQ House, as a test-bed for an integrated louvre facade system which relies on living algae for a self-regulating degree of shading, and for active power production.
One also doesn't want to be an arm-chair critic in the face of the scientific prowess such august team would have invested in developing the technology. Technical details available on the internet are sketchy, so it's altogether a bit dangerous to try to infer how such a system might perform. But precisely because as usual, the press releases are repeated so uncritically, a little bit of scrutiny doesn't go amiss.
|Detail of louvres|
These are baseline questions one must ask to define the grounds for comparing the proposed technology to possible alternatives. The facade represents a surface with a specific maximum energy budget, especially in terms of the solar energy falling on it. That solar energy can be absorbed and converted to useful form by a number of alternative means, each with different efficiencies, and producing different grades of energy. For instance, photovoltaics might be only maximum 20% efficient at the moment in producing electricity, but that electricity is the highest grade energy used in the building. And combined with heat recovered from behind the PV panel at temperatures useful for direct heating or domestic hot water, or even running absorption chillers, the yield of such a wall might be considerably higher. We would need a comparable overall efficiency evaluation of the algae panels, to know whether the effort is worthwhile, because the disadvantages of the relatively complicated construction and conversion (if I infer it correctly, may be simply too great to justify it as an energy technology.
|The original post doesn't identify whether this is a photo or a rendering|
Meanwhile, the appearance of BIQ House adds new meaning to the much abused term 'green building'. It's very green indeed. Working in there will either be extremely calming (think 'green rooms' for actors before a performance), or your colleagues will look like they are about to be violently ill. I am eagerly anticipating the interior photographs, and indeed further technical information.