—— Lu Shan

Improving the quality of underground environment

The Significance of Sunlight to Underground Space

physiological

psychological

Saving energy consumptionillumination

refrigeration

The permeability of sunlight and natural scene is key factor in design of underground environment.

Underground buildings need more lights and ventilators to make up illuminance deficiency and bad ventilation condition.

Principles of Sunlight Collecting

Passive sunlight collecting the structures or devices accept sunlight passively, without automatically tracing the obit of the sun

Active sunlight collecting the active sunlight system automatically tracks the sun with electricity control or light control

collecting transmission

defusing

replacement

Passive sunlight collecting system

Central atriums

The central atrium solve the problems of closure and lacking of natural scene of underground buildings. And it is also the most diversified, attractive and nature-intimate space, easy to become a mark of the building.

Eton Center

Passive sunlight collecting system

Sunken plaza is some encircled open public space which totally or partially sinks into the surrounding environment, turning the underground building into semi-underground, providing ways to solve the problems of lighting, ventilation, fire prevention and the like for commercial and transport facilities connected to it.

“Watermark City” plaza in Hang Zhou

Sunken plazas

Passive sunlight collecting system

Sight light wells and skylights mix with surrounding environment so that can not only play a role in lighting and ventilation but also harmonize the surface scenery planning.

Sight light wells and skylights

Napoleon Square

Innovative designs for underground or semi-underground buildings ----- reflectional skylight & sunken sunlight room

Passive sunlight collecting system

Designed by engineer Zhu Daming and Yan Peng from the 3rd research institute of engineering corpsman. Using the principles of reflection, the designs can bring more sunlight into further depth of the room, thus improve the quality of the inner environment of underground or semi-underground buildings.

Reflectional skylightSunken sunlight room

Passive sunlight collecting system

Passive light pipe

The passive light pipe can be viewed as an improved skylight. In a sunny day, it can bring soft sunlight into dim space indoors or the rooms contain combustibles and don not fit to use electric lights.

Collecting dome:PC or PMMA,reflection ridges;Pipe: 3M’s prism film, >99%;Diffuser: turn point light into more soft ray

Passive sunlight collecting system

Detail treatments

Some Detail treatments used in ground buildings could also be used for improving the lighting condition in underground space.

Ground building reflection structures

Lenses combined with skylights

Advanced roof style ---- DSWS

Active sunlight collecting system

Lens reflection system

collector: made of lenses or reflect mirrors, collect and concentrate sunlight; light well: well like structure, transit light; final devices: diffuse the light.

The idea was first raised by P Y Nagi in “Sunlighting for inner space”. Though the system is not widely used today, Nagi hoped it could arouse the attention of the persons of same profession in science and architecture

Active sunlight collecting system

Example 1:

Daylighting system in C\ME building of Minnesota University

the result showed that the total cost of this system was just 1/8 of the cost of a normal artificial illumination system.

Active sunlight collecting system

“Sunflower system”

More than 400 international patents and decade-long operation practice in the market abroad. GPS traces the sun precisely anywhere; Special six-bundle optic fibers transit the light to a length over 3kms; Final diversified diffusers possess many different functions.

Active sunlight collecting system

Example 2:

Qinghua low energy consumption

demonstration building the test result showed that the system could transit the light to a distance of 200m, and a depth of 30m underground.

Conclusion

To permeate sunlight and outer natural scenery through technology methods means a lot to the environment improvement of underground spaces. Many experts in the fields of building illumination have began to realize the importance of day-lighting and try to investigate such products of our own IPR. We will make a breakthrough in the not-too-distant future!

Thanks !