The solar chimney increases the efficiency of natural ventilation

News, 04/01/2021

On the roof of the Bustěhrad laboratories of the University Centre for Energy Efficient Buildings of CTU, a solar chimney is in full operation . This device uses accumulated heat from solar radiation for natural ventilation of buildings. Thanks to this, it is possible to ventilate for a longer period of time without the need for electricity.

The Indoor Environment Quality Research Department of CTU UCEEB made a functional sample of a solar chimney that it differs from similar types of devices by three glazed cavities. In them, air heated by the sun prevents turbulent flow and thereby increases the efficiency of natural ventilation, which works even during power outages. The aim of the experimental operation is to quantify the benefit for building ventilation in the conditions of the Czech Republic and to make a comparison with normal shaft ventilation. Data collection and ongoing evaluation are currently underway.

The solar chimney is 45 m high. It has an approximately square floor plan with dimensions: 0.9 x 0.75 m. The glazed part is glazed with thermally insulating double glazing. The cavity is painted black inside and divided by two glass partitions. The back wall and side walls are insulated with 120 mm thick thermal insulation. At the top, the chimney is topped by two wind vanes. This type is structurally and dimensionally designed in such a way as to enable use for individual apartments of an apartment building . It can be placed on the roof or on the facade of the building.
The implementation of the functional sample and the investigation of its effect was supported by the Technological Agency of the Czech Republic within the project No. TH02030797 – Environmentally friendly resilient apartment buildings.