Intelligent sun shading control system: wind and sun included in the calculations

17.07.2017 -  

Berlin has acquired yet another architectural highlight in the 50Hertz Netzquartier in the Europacity district. The new company headquarters of this electricity transmission system operator is close to the main railway station and the Museum of Contemporary Art. Honoured by the German Sustainable Building Council (Deutsche Gesellschaft für Nachhaltiges Bauen DGNB e.V.), the building’s many delights include highly efficient sun shading by Warema. Its intelligent control system not only implements a wind appraisal, but also annual shading for every single room with absolute precision.

Visitors to Europacity in the heart of Berlin cannot miss the 50Hertz Netzquartier. Constructed on a site measuring approximately 8140 square metres, this exceptional building that blends perfectly with the surrounding area instantly catches the eye. The Love architecture and urbanism architectural offices of Graz won the international architectural competition with this exciting design. Measuring some 55 metres in height, it comprises seven L-shaped bases with a six-storey tower and an underground level. The open, transparent structure of the building is notable for the reinforced concrete cores and a network of white supporting and intersecting façade supports, on the one hand symbolising the company’s purpose, and on the other creating a reference to the railway area with its steel bridges.

The approximately 650 employees were actively included in the design of the open office landscapes. During the planning stage, every department defined its own working world as appropriate to its particular requirements, with the result that no two storeys are the same. Every floor offers opportunities for working in a small or large group, privacy when dealing with phone calls or to settle down on one of the outdoor terraces with a notebook. When it gets dark, LED lamps lighten the network structure, completely transforming the overall appearance of the building.

Intelligent implementation of the wind appraisal
There is one thing that this all-glass building, with its countless balconies and terraces, needs above all else in order to create a pleasant feel-good and working climate on the inside, and that is efficient sun shading. To this end, the design includes over 1000 motorised, wind-stable external venetian blinds with 93 mm dim-out slats and rail guidance.

However, the particular requirements of the 50Hertz Netzquartier went far beyond that. Due to its exposed location and the height of the building, the client also commissioned a wind appraisal that also had to be taken into account. This was the work of Ruscheweyh Consult GmbH of Aachen, who tested a complete model of this and the surrounding buildings. The construction project was divided into 54 wind zones with various wind characteristics.

The Warema BAline control was used to implement the wind appraisal. Thanks to the precise calculations, Warema needed only a single measuring point to provide the system with information on brightness, precipitation, outside temperature, wind speed and wind direction. The Warema climatronic® 3.0 KNX central weather unit (consisting of the Warema climatronic® control panel, KNX Gateway and Warema climatronic® weather station) in conjunction with Warema BAline KNXMCM completely replaces the 54 individual wind monitors for the various wind zones. The measured values are passed on to the programmable logic module BAline KNXMCM, the system’s “brain” that converts them as per the wind appraisal into move commands for the sun shading system.

A single sensor for 281 shading zones
Along with wind appraisal, the shading correction (annual shading diagram) with resolution per room is another special feature of the sun shading system at the 50Hertz Netzquartier. Warema calculated and evaluated the changing shade progression using a computer model of this and the surrounding buildings, including the Tour Total, the headquarters of the French energy company Total, and the Federal Institute of Forensic and Social Medicine. Depending on the season and the position of the sun, neighbouring buildings cast shadows on the windows of the 50Hertz Netzquartier that render additional sun shading superfluous as it would keep daylight away unnecessarily. Every room was designed as a shading zone that needs shading as determined by external reference points based on the measured values of the Warema climatronic® 3.0 KNX central weather unit and on the calculated incidence of light. In all, there are 281 zones. The sun shading system acts as if there were a sensor in every single room that responds as sunlight falls on the window. In fact, though, there is only a single sensor on the roof.

The slats of the sun shading product or daylight system adjust automatically in stages as an additional function to the sun control. Depending on the current position of the sun, it facilitates the best possible daylight utilisation and optimum heat protection by blocking out direct sun rays and allowing as much diffused daylight as possible into the room. Slat tracking is effected in five stages to place the external venetian blinds at the optimum angle to the sun. Slat tracking and shading correction are necessary for achieving energy efficiency rating A or B as per EN 15232 and VDI 3813 Sheet 2. The sun shading elements can also be operated manually by means of push buttons connected to the actuators for room control.

First building to receive DGNB Diamond level
The 50Hertz Netzquartier is the first building in the world to be awarded Diamond level by the DGNB, the German Association for Sustainable Building. This certificate acknowledges the sustainable construction as well as design and architectural quality. The award is the result of a pilot stage that the DGNB e.V. launched in 2015 together with the Federal Chamber of Architects (BDA). It is only awarded to completed buildings of superlative architecture that have already received, or are striving for, DGNB Certification in Gold or Platinum.

Copyright: Huthmacher/Warema. No fee for photo publication provided source indicated. A copy of the publication is requested. Photos may not be used for advertising purposes.