The "SUNVENT" project at Frederiksberg, Copenhagen Highlight concerning a solar low energy retrofit project "ventilation towers" at Lineagaarden, Frederiksberg.

In many cases it is not possible and not popular to make a space-demanding shaft for ventilation ducting inside a building. An alternative to this is instead to install a ventilation tower on a south or east/west-facing facade of the building and place all the ducts work here. At the same time it is possible to design the ventilation tower so the surface of it can be used to produce solar energy.

The "solar ventilationtower" is build with a surface of dark green painted perforated aluminium plates as an unglazed solar collector which can preheat the ventilation air. A similar solar collector design which is known from the so-called "Canadian Solar Wall" -

In figure 1 above you can see how the architect Klaus Boyer Rasmussen from SolarVent proposed to integrate "solar ventilationtowers" of this kind in the EU-Thermie supported "SUNVENT" project in the housing estate "Lineagården" at Frederiksberg in Denmark. A project which is beeing realised for 167 appartments with Frederiksberg Housing Fund as builder and Cenergia as project coordinator during the summer 2000. For some of the "solar ventilationtowers" it is also aimed to test a solution where building integrated PV-modules is placed in the top part of the "solar ventilationtower" to run the ventilation fans.

In figure 2. is seen a picture of the first installed "solar ventilationtower at Frederiksberg.