This new 8-storey building is housing the Office for the Environment and Energy of the Canton of Basel-Stadt. In keeping with the tasks of the...
AUE – Amt für Umwelt und Energie
Architect Sven Kowalewsky
Jessenvollenweider Architektur GmbH
``Thanks to coloured dots and a structured surface of tempered fused glass, the play of light on the modules changes depending on the viewing angle and sunlight.``
A solar experiment

This new 8-storey building is housing the Office for the Environment and Energy of the Canton of Basel-Stadt. In keeping with the tasks of the office, the zero-energy office building was intended to become a beacon for resource-conserving, efficient construction and an inspiration for other building projects. At the heart of the new building is the overall energy concept: a highly thermally insulated building envelope, district heating, use of rainwater, photovoltaic facades on all sides to generate electricity, controlled ventilation with heat recovery, optimal use of daylight and efficient lighting. Furthermore, the highest attention is paid to building ecology through the use of pollutant-free natural building materials. The use of predominantly regional materials and recycled concrete has significantly reduced grey energy. In order to optimally integrate the building into the cityscape, a special glass was developed especially for this project, which shows a three-dimensional, irregular liveliness that changes in the light. Metallic colour dots integrated into the glass also break up the dark base colour of the PV cells and overlay it with warm tones. The appearance of the cladding changes depending on the viewpoint and on the incidence of light. A detailed testing and sampling process made it possible to take into account the diverse demands for maximum performance, durability and aesthetics of this lighthouse project.

Plan of the office area from the first to the fifth floor.

The AUE project is characterized by PV facades made of monocrystalline cells that generate energy over all sides of the building, including the less sunny areas.

The new building is a modern, energetically optimised and sustainable building that fits perfectly into the listed context. Moreover this eight-storey building is the first office building in Basel to be certified with the Minergie-A-ECO label.

Building characteristics
  • Building typology
  • Construction type
  • Year of construction
    2019 – 2021
  • Energy reference surface
    2.100 m²
  • Energy index
  • Energy labelling
Active solar surface 1.132m²
Active solar surface ratio >75%
Peak power 163 kWp
Building skin application Flat roof Cold facade
Energy production
Source: BE Netz
not available
Building skin
  • Application
  • Description
    Composite wood-concrete flat roof with 25 cm of thermal insulation. Extensive roof greening.
  • U value
  • Fastening system
  • Other
    Recycled concrete was used for all components
  • Application
    PV cladding integrated in a cold facade
  • Description
    Concrete walls insulated with 20+19 cm of mineral wool.
  • U value
  • Fastening system
    Continuous fixing system (aluminium tracks)
  • Other
    The wooden rib elements are standardised and were delivered to the construction site in transportable sizes.

The wooden rib elements are standardised and were delivered to the construction site in transportable sizes. Photo credits: Kenneth Nars.

To meet the aesthetic requirements imposed by a city center location, the photovoltaic (PV) modules have been assembled with SEEN Elements and a special structured glass of Crea-Glass Unterseen.

  • Application
  • Description
    Triple glazing with wooden frame
  • U value

The wall is completed with a closed cavity window type that has a very good U-value and integrates an energy-optimised solar shading system in the form of reflective louvres to direct daylight and minimize maintenance costs. Photo credits: Céline Dietziker – Architektur Basel.

One of the special features of the building is the skeleton construction in wood-concrete hybrid technology. Photo credits: Häring AG.

BIPV module
  • Manufacturer
    Megasol Energie AG
  • Cell technology
    Mono-crystalline PERC
  • Dimensions
  • Front glass type/customization
    Custom-made structured glass from Crea-Glass GmbH assembled with SEEN elements (small metallic shiny dots with titanium nitride coating and larger red-yellow color-shifting dots).
  • Specific power
    Approx. 144 Wp/m2
  • Specific weight
Technical details

The facades are made of wooden elements applied to the outside of the raw structure. Sound-insulating and flush mounted, the closed cavity windows are fitted with vertical blinds inserted into the ventilated cavities. The glass facade on all sides of the building is ventilated and produces electricity thanks to integrated photovoltaic elements. The modules are characterised by a plasticity given by the cast glass and have different and variable dimensions compared to the field of the modules laminated there. The resulting variable and transparent edges allow a glimpse of the fascinating substructure.

Projection 1:10
Hotspot image
Vertical section
Hotspot image
  • Total cost of the building
    10.31 Mio CHF
  • Price per m³  

The PV facades are expected to produce approximately 53 MWh of electricity per year, which corresponds to the annual demand of about 12 single-family homes.

Parties involved
  • Owner
    Immobilien Basel-Stadt
  • Architect
    Jessenvollenweider Architektur GmbH
  • Construction management
    b+p baurealisation AG
  • Photovoltaic consultant
    Megasol Energie AG
  • Photovoltaic installer
    BE Netz
  • Facade installer
    GKP Fassadentechnik AG
  • Photo
    Jessenvollenweider Architektur GmbH
Awards and recognitions
  • Publications
    Hochparterre Solaris#6 – Das Diskurs-kraftwerk by Palle Petersen – March 2022 (in DE, FR, IT)

    Tec21 – Alles Gold, was glänzt? – 25.2.2022 (DE)