The facade glazing does not go out of date for several decades. Buildings lined with glass have a modern, attractive look and provide unlimited opportunities for self-expression of the architect and the customer, thanks to the selection of glass of different shades, creating facets and an play of reflections.

This results in increasing the requirements for thermophysical and operational features of such facade. Sunshine with infrared thermal component of the spectrum, is passing through the glass barriers.

The task

The Department of Technical Policy of JSC Russian Railways, within the implementation of progressive policies of energy-saving investigations and technologies, has initiated the "test drive" of modern solutions in its landmark facility – the Leningrad railway station.

The task was set to implement in a test mode a complete solution to maximize the use of natural sunlight coming through the glass facade, while reducing the blinding effect of the flecks of sunlight which interfere with employees, and reduce the load on the HVAC systems by reducing entering excessive heat in premises.

The solution

Relating the question of energy saving, two key factors should be highlighted: Operation of air conditioning systems and use of the additional lighting during daylight hours.

An alternative to artificial lighting is 3M™ film that redirects sunlight.

The film consisting of microstructured prisms optically redirects to the ceiling and dissipates more than 80% of daylight, ensuring its uniform distribution for natural lighting in the inner space of the room. The film was installed on the windows of the western and eastern facade of the railway station.

In order to reduce the load on the air conditioning system the 3M™ Neutral 35 Exterior film of a series of exterior 3M solutions for the effective sun protection with the index of white light transmission of 35% was selected. This film is simultaneously solves two problems — decreasing heat gain from solar energy and reducing the effect of flecks of sunlight by 50%.

During the calendar year, through the western facade of the railway station (465 square meters) the energy of 109,857.23 kW/h enters, through the window with the exterior film Neutral 35 exterior applied the rate will make 58,997,40 kW/h. The result is a reduction of heat gain by 46%, in proportion the load on the air conditioners is reduced.

For calculation the irradiation data of solar energy based on the geographical location of the railway station, as well as the factor of heat gain through the multiple glazed unit of the building were used.

It is important to note that the film color harmoniously integrated into the architectural appearance of the facade, emphasizing the designer's style of color combination of materials.

Truong Duy