Calcareous dream

Calcareous dream

ERDBERG (AT) - In today's enthusiasm for sustainable development, the hype surrounding many projects often involves their near-zero energy consumption or diminutive carbon footprint. But in the case of Coop Himmelb(l)au's award-winning office tower, the so-called 'energy-active' design is in fact projected to produce more energy than it uses. Town Town Erdberg, located on the outskirts of Vienna adjacent to a subway line and nearby the airport and a major highway, intends to be the distinctive centrepiece for sustainable design in this emerging urban zone.

Like an echinoderm escaped from the sea, the building's eccentric architectural form derives from a spiny skin that envelopes both slab and tower elements, and was developed to exploit local climatic conditions. In-depth analyses of wind flows and sun trajectories at the site led the architects to two key energy harnessing elements: the external facade's optimum geometry, consisting of folded sheet metal facets and special panels coated with a photovoltaic laminate to capture solar energy, and the integration of a large turbine on the tower's top that will produce wind energy. In addition, the entire structure can be naturally ventilated through operable windows or by adjusting the climatic skin.

Together with low energy consumption and environmental control systems, the sun- and wind-energy harvesting strategies offered by this example of environmentally intelligent building design claim to produce more energy than the building actually consumes. Further, the structure is quite efficient in terms of internal space; the ratio of net usable floor area to gross floor area is 86%, as opposed to 82% in a conventional building. No wonder, then, that functionally and climatically optimal Town Town Erdberg is slated to receive the Sustainability Award of the 2010 MIPIM Architectural Review Future Project Awards. (Dutton R. Hauhart)