The National Aquatics Center, or the "Water Cube," fully represents the concept of "Green Olympics," in terms of architecture, outside layer engineering, environmental protection in the areas of material, energy and water resources as well as the indoor environmental quality, according to a BOCOG official.

A worker walks inside the National Aquatics Centre, known as the 'Water Cube', after its plastic film exterior was completed in Beijing December 26, 2006. The plastic film on the outside layer of the centre is known locally as the membrane structure. Swimming, diving, synchronised swimming and the water polo final will be held in the centre during the 2008 Beijing Olympic Games.[Reuters]

The "Water Cube" absorbs solar radiation and reduces thermal loss, guarantees the incoming of most of the sunlight which serves as the thermal source of swimming pool water, Yu said in a recent interview with the press.

The maximum use of natural ventilation and lighting features the environmental design of the project's outside surface, to ensure temperature and humidity control in different sections of the swimming pool and provision of comfortable indoor environment for athletes and spectators, Yu added.

Workers install the last piece of the National Aquatics Centre's plastic film exterior in Beijing December 26, 2006. The plastic film on the outside layer of the centre, which is also called the 'Water Cube', is known locally as the membrane structure. Swimming, diving, synchronised swimming and the water polo final will be held in the centre during the 2008 Beijing Olympic Games.[Reuters]

According to Yu, guided by the concept of sustainable development, constructors choose innovative energy-saving materials and products to reduce inside and outside pollution.

The realization of "green Olympics" in the "Water Cube" project set a good example for other Olympic venues and the construction of Beijing's urban projects, Yu believed.

The project uses the state-of-the-art ETFE material which is light but very strong. The blue bubbles outside the National Aquatics Center comprise over 3,000 air cushions, which look like an entirety but actually they are relatively independent from each other, providing convenience for replacement of individual cushions when needed.

The swimming pool is 13 meters deep, which can reduce the interference of water temperature variation, according to project manager Sun Hongzhuang. The temperature of swimming pool is projected to be kept at 28 degrees Celsius, the best suitable for swimmers, Sun said.

During the Olympic Games, the venue can sit 17,000 spectators. "We've made lots of personalized treatment to let the spectators at every corner to see athletes' performance," said Sun.