/// Norddeutsche Landesbank administration center Hannover (D)
Building owner:
Norddeutsche Landesbank Girozentrale, Hannover
Completion / Occupation: 04/2002
Building area: 77.000 m²
Architect:
Behnisch, Behnisch & Partner, Stuttgart
Structural engineer:
Arge Wetzel + von Seht, Hamburg; Pfefferkorn + Partner,
Stuttgart
Façade:
Erich Mosbacher, Friedrichshafen
Building physics:
Horstmann und Berger, Altensteig
Building services MEP:
ArgeTGA, Becker & Becker, Braunschweig; Lindhorst,
Braunschweig; Grabe, Hannover; Taube – Göerz-Liegat,
Hannover; Federführung: Gierke, Braunschweig
Lighting engineering:
Bartenbach Lichtlabor, Aldrans / Innsbruck (AT)
Project supervision:
NILEG, Hannover
Climate Engineering:
Transsolar Energietechnik GmbH
Project manager: Peter Voit
Brief:
A transparent office complex with a dazzling 17-story high-rise and a compact block construction not exceeding seven stories that wraps around a generous inner courtyard.
Environmentally sound measures were to be implemented while keeping within financially justifiable bounds. The objective was to comply with the thermal protection regulations in place at the time. One specific aim was to do without room air conditioning whenever possible.
Site factors:
– Geographic position: latitude 52.37° north, longitude 9.72° east, 63 m elevation above sea level
– Solar irradiance (on horizontal surface per year): 934 kWh/m²
– Humidity (1%): > 12.4 g/kg
– Local temperature conditions: min -13.1 °C, max 32.5 °C
– Average temperature of hottest month: 16.8 °C
– Mean annual temperature: 8.7 °C
– Temperature difference day/night during hottest month: 10.4 K
– Mean wind velocity (at 10 m): 4.0 m/s
– Main wind direction: 260° WSW
– Local ancillary conditions: downtown location beside a 6-lane street
Concept:
– Underground heat exchangers for seasonal hot and cold thermal storage
– Exterior solar protection with optimized daylight redirection
– Building component cooling
– Window ventilation for overall ventilation as well as night flushing, partially in combination with double-skin façades
– Vacuum tube collectors for water heating
– Absorption cooling machine
Tools:
– Weather data analysis
– TRNSYS for thermal simulations
– TRNSPILE for the sizing of the underground heat exchanger/building component activation systems
– FIDAP for air flow simulations of the double-skin façades and halls
– RADIANCE for shading projections
– 1:20 sectional model for visualizing air flow