Intensive ventilation through windows during the night is a cost-saving and energy-efficient method of cooling buildings in the summer. The right window technology is crucial for automatically controlled night cooling.

Reduced performance due to heat

Offices, schools and public buildings often become unbearably warm in the summer, and people, equipment and lighting contribute to the heat. Warm solar rays enter rooms via large glass windows. People begin to lose their concentration and their performance deteriorates. The building must be cooled so that people who are in the room feel comfortable and remain mentally fit, despite high outside temperatures.

Night-time ventilation saves energy

Controlled natural ventilation saves a lot of energy, as it uses the natural pressure differences between at least two openings (e.g., windows and doors) of a building to the outside for air exchange.

Automatic night-time back cooling: useful for public buildings © Jürgen Pollak / GEZE GmbH

For night-time back cooling, automatically controlled windows direct the heat generated by solar radiation and internal sources to the outside during the night and cool, fresh air to the inside. The supplied fresh air ensures a pleasant indoor climate through a pleasant temperature and good air quality.

In the air tonight

The cool night air acts as a natural source of cold – a sustainable, energy-efficient, natural and environmentally friendly option. In new buildings, air-conditioning is increasingly combined with thermal core activation.

Modern window technology ensures optimum night-time back cooling. Window fronts are automatically controlled, and a central control unit ensures that ventilation scenarios such as ventilation periods can be defined and easily changed.

The parallel opening of the window ensures optimum air exchange so that cool air can flow in from below at the same time as warm, stale air escapes upwards.

The automatic window control for night ventilation can be networked with the building control. If the building technology automated in this way reacts automatically to climatic influences and changes, it turns buildings into “smart buildings”.

Upgrading to smart buildings

Automatic window controls from GEZE enable natural night-time back cooling. The window drives can be controlled precisely and allow a variably adjustable opening width for each window, enabling individual ventilation concepts according to customer needs.

Sensors ensure complete safety – presence detectors monitor the closing edges and prevent injuries due to automatic opening and closing. Wind and rain sensors give signals to close the windows and protect the building stock from damage.

IO 420 Interface module for connecting GEZE products to the building management system
IQ box KNX Interface module for connecting the Slimchain, Powerchain, and E 250 NT window drives

Requirements for automatic window-based night-time back cooling

  • A moderate climate: The outside temperatures at night must be well below the temperatures in the building for a sufficient period.
  • Good outdoor air quality: Few odours, pollutants, fine dust.
  • Protection against burglary: Windows can be controlled separately in accessible areas such as the ground floor, protection by means of window guards or by special construction (parallel-opening vent windows).
  • In heavy rain or wind: Structural weather protection or automatic closing of opened windows.

For more information, contact GEZE:
Tel: +27-11-315-8286

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