PhysOrg points us to a press release from SunPower, a subsidiary of Cypress Semiconductor, which just completed construction of a "building integrated photovoltaic" system using its high-efficiency A-300 solar cells. The A-300s are useful for architecture for a number of reasons: they look neutral/dark grey in color, as opposed to the shiny blue of most solar panels; the connection systems are designed not to be externally visible; and (most importantly) they produce nearly a third as much more power per square meter than most other cells (21.5 percent efficiency instead of 12 to 15 percent), and remain very sensitive under low light conditions. The system will produce up to 1.8 kilowatts.
The building, which will house the headquarters of BioHaus (which makes solar power gear, unsurprisingly), is located in Paderborn, Germany.
Set aside the PR-speak and think about the implications of building-integrated solar. The idea of covering hundreds of square miles with solar panels is a non-starter, for a variety of environmental and efficiency reasons. There are much better ways of using solar power as part of a changing energy strategy. But we don't want to have the power grid go away, and neither do we want to be dependent solely upon a small number of large centralized generators. The value of distributed renewable generation isn't to allow "off-the-grid" buildings, or even to replace bigger systems entirely; distributed renewables give the power system some flexibility and a "cushion" in case of problems.
While bolt-on solar power systems have their place, distributed renewables will really come into their own when they are considered part of the building-as-a-system, not an optional add-on. Sustainable building design is really taking off all over the world. Buildings that combine efficient design and integrated solar could potentially be able to feed power back in to the grid consistently, only needing to pull grid power in unusual circumstances. Building-integrated renewables make it possible to start thinking of buildings as power sources for cities, part of the overall sustainability system of the urban environment.
This looks promising. The main caveat is not to embed materials with vastly different lifespans into one structure, in a way that the materials can't be separated. It's the weak-link-in-the-chain argument: the building will only live as long as its shortest-lived component, unless the building is easy to adapt and upgrade. Photovoltaics appear to have about a 20 to 30 year lifespan, so they should not render obsolete other parts of a building that can last hundreds of years.