Objective and purpose The most state-of-the-art natural gas power plant in the world has recently been completed on Lausward in Düsseldorf’s harbour. It has been supplying the city with climate-friendly electricity and district heat since the beginning of 2016, and is therefore making a considerable contribution towards a more secure energy supply within the city and region. The new natural gas power plant is an important milestone on the way to a carbon-neutral city, which the state capital is striving to achieve by 2050.
In order to provide the ambitious project in its exposed location with an attractive look, Stadtwerke Düsseldorf and Landeshauptstadt Düsseldorf initiated a European-wide competition for the design of the building envelope. Out of approximately 40 proposals that were submitted at the beginning of 2013, kadawittfeldarchitektur was awarded first prize for their design of the power plant’s exterior appearance.
Location in the city The new build is located on Lausward, an area just south of the city centre at the bend of the river Rhine in immediate vicinity of the harbour. The difficulty of the location, overshadowed by the old power plant structures, was to strengthen the affiliation of the two plants as an ensemble and give the symbiotic relationship of old and new a powerful force. At the same time, however, the new power plant was to stand out as an eye-catching structural logo, be visible from afar, as well as appear warm and welcoming up close.
Design / concept A facade made of steel frames provides the various parts of the new power plant with a uniform, all-embracing skin. The height and width of the individual elements adapts to the technical installations enclosed in the interior. The frames and the joints in between interact in such a way that they produce a skyline silhouette giving the powerhouse a sense of identity. At night, when the joints are illuminated, the new state-of-the-art natural gas power plant can be seen from a distance, thus promoting the image of an innovative energy provider.
The largest frame element completing the plant in the northeast, the so-called 60-metre-high City Window, incorporates the power plant’s main stack – at approximately 63m, the highest peak within the grounds. The City Window is fully glazed on two sides, the one facing the city and the one opposite looking out onto the power plant. Visitors taking part in a guided tour can use a lift to reach an observation deck 45 metres above the ground. It is from here, through a glazed facade, that they can enjoy panoramic views south across the plant as far as Cologne and north across the river Rhine to Düsseldorf’s city centre.
Principle of the facade and illumination The facade of the new power plant is not only a climate barrier and sound proofing system but also an enclosure for most of the technical facilities, including the smokestack. The technology in the interior is concealed by a comparatively small-scale, flexible construction of different sized frames, which despite its fragmented nature successfully generates a large connected structural volume. Since the dimensions of the building envelope respond to the technical requirements of the interior, it could also easily adapt to changes that took place during the planning of the plant.
All frames are generally parallel to the lines provided by the power plant layout, except for the element at the northeast end of the facility, the co-called City Window, which is off axis and turned by approximately 15 degrees towards the city centre with the effect that the “good” side faces Düsseldorf as well as the Rhine Bend. The facade concept is based on the contrast between the lighter protruding frames and the darker set-back joints. The protruding frames are made of folded steel sheet sandwich panels with a silver coating. The sides of the frames are made of the same steel sheet sandwich panels, however, with a black coating in order to take a backseat to the lighter more visible exterior cladding. The joints between the individual frame elements are set back by approximately 50 cm and closed with black perforated metal plate. At night, LEDs fitted along both sides illuminate a reflector panel behind the perforated metal plate and light up the joints, which simply appear dark during the day.
The rhythm of the facade frames and the intermediate joints characterise the silhouette of the power plant and, in an abstract way, convey the meaning of energy to the outside world. During the day, the interplay of frames and joints ties the heterogeneous elements together creating a uniform appearance. The joints shine brightly at night dematerialising the large-scale plant and creating a barcode image, thus displaying the continuous generation of energy throughout the city.
Construction, material concept and interior design The concept of the primary structure and the facade panels was adopted from standard power plant constructions. The conventional appearance of the outer facade elements, however, has been modified to enhance the architectural scheme: where the elements protrude, the depth of the steel sheet sandwich panels was increased by using spacer pieces; moreover, the corner and edge design was adapted to achieve a more monolithic appearance of the frame elements. The configuration of the sandwich panels was complemented by adding black perforated metal plates to the joints.
The structure of the City Window includes a steel framework construction which is independent from the boiler house and the tower. In order to adopt the technical character of the power plant in the interior of the City Window, the main structure of the hall is made of predominantly bolted rolled steel sections to which the facade, an aluminium composite panel construction, is connected with welded plates. The steel framework and the facade construction are coated with anthracite-coloured micaceous iron oxide paint. Other materials characterising the atmosphere of the interior include galvanised steel, stainless steel, glass, exposed reinforced concrete (polished slipform concrete is used around the tower) and industrial floor finishes in the public areas, in particular dark grey polished screed. The underside of the City Window’s roof and the side walls are clad with folded aluminium sheet lamellae. These are designed to reflect the light at night and provide sufficient depth for the accommodation of smoke exhaust and ventilation ducts.