This device was invented by Rau Architects Amsterdam in cooperation with Boon entrance systems. Thomas Rau: "one round is enough for a coffee, two for an espresso"
from their website:
Natuurcafé La Porte is a joint venture between the Antropia Cultural and Congress Centre, the Utrechtse Heuvelrug National Park, tourist information agency Utrechtse Heuvelrug, the restaurant Groenland and the Reinaerde Foundation. The building features a world first in the form of an energy-generating revolving door. Initiated by RAU, the door was developed Boon Edam especially for Natuurcafé La Porte.
Healthy living, nature and energy efficiency are central features of the design concept. Through the use of technologies such as the geothermal heat pump, heat recovery, solar collectors and boilers for tap-water heating; soon to be supplemented by a wind turbine and photo-voltaic cells, Natuurcafé La Porte is (almost) entirely energy-neutral. In its construction, RAU has intentionally selected recyclable, allergy-free materials based on natural or recycled raw materials.
The station restaurant is not only energy-neutral, it offers visitors an all-round healthy experience. Travellers have the chance to enjoy a few moments to themselves, in surroundings that are in harmony with nature.
This is reflected in the organic food provided in the restaurant, the materialisation of the space and the energy-efficient technologies used in the building. The energy-generating revolving door is a good example. When entering, each visitor thus generates electrical energy, which, metaphorically speaking, will be used for brewing his or her cup of coffee.
The existing structure has been devoted to the reuse of the space. By removing the old partition walls, an open space has been created in which various functions overlap. The removal of closed wall panels on the platform side has created new exterior views. The difference in ceiling heights has been used to introduce extra glass, so that the light penetrates deeper into the space.
The ambition was to achieve a restoration of the station which was not only energy-neutral, but which offered visitors an all-round healthy experience. Here, travellers have the opportunity to take a few moments for themselves in surroundings that are in harmony with nature. This is reflected in the organic food provided in the restaurant, the materialisation of the space and the energy-efficient technologies used in the building.
Travellers can visit La Porte before or after their trip for healthy organic food, to get information before visiting the National Park or hiring a bicycle. The restoration of the station has thus grown into a link and relaxation point between travel and nature.