In November 2006, with the idea of an 'energy spiral', Peter Lorenz won the contract put up for tender by the property developer. The geometry of a 'band-spiral' creates a unique tunnel-like area which, by means of the side intersection surfaces exposed to light, throws a fascinating ray of light onto the slanting walls.
The spiral begins at entrance of the Gienger showroom at the east of the building by means of a wide open projecting roof. Opposite, at the west side, a similar opening is put to use for the cash and carry wholesale store. The slanting external surfaces are fitted with both solar-thermal and photovoltaic panels. The latter of these could, in the course of new developments, be fitted with products which at the moment are still being devised. The outer shell is made up of solar panels, photovoltaic panels and metal and glass elements.
The architect has named the project Ener(gie)nger – a coinage of the words 'energie' (energy) and the name Gienger, the well established domestic engineering wholesale business. At the core of the exhibition hall are the various bathrooms on display, as well as the 'educational energy trail' – an exhibition of current installations and equipment belonging to the energy-saving sector. Since its introduction, this 'trail' has been accepted very quickly and intensively; it plays an important role in the understanding of technology, which in turn means that such technologies can actually be put to use.
An inviting roofed lobby-area opens itself to visitors; a 'right of way' for customers. Inside exhibition areas at various levels connected by ramps provide a unique spatial experience. Innovations concerning sustainability include:
• Energy management with use of renewable energy.
• Educational energy trail with the latest of technologies (Current resources available, renewable raw materials, regenerative energy therefore recuperative energy).
• 250 sq m solar panel area - solar thermal energy for heating and cooling the building
• Ground water well for heating and cooling purposes.
• Highly efficient ventilation system with heat recovery.
• Combined heat and power plant – electro and thermal energy.