Yantai Sun Tower by Open Architecture

Yantai is located about 500 km southeast of Beijing on the coast of the Yellow Sea. The Chinese government established a special economic zone here in 1984, the Yeda Development Zone. Today, it is considered an important location for the Chinese automotive supply industry, and Foxconn operates a large factory here. Due to its coastal location, it is also a popular residential area and attracts tourists.

Parallel to the course of the sun 

With the Sun Tower by Open Architecture, the satellite city finally has a cultural centre with a library, exhibition areas and viewing platforms. Archaeological excavations have shown that early solar cults took place in the area around Yantai. The architects took this as an opportunity to design their cultural centre as a modern solar observatory. The 50-m tower is oriented so that its northern edge runs parallel to the midday sun at the summer solstice. The entrance tunnel from the city faces the sunset on the winter solstice.

Observation tower with two faces

The Sun Tower turns its back on the city and the industrial area behind it with its closed concrete walls. Towards the lake, it opens up with open staircases, viewing terraces and a large auditorium on the ground floor. The structure consists of two concrete shells, connected and reinforced by stairs and ramps. The lower concrete shell also covers the amphitheatre, reflecting the sound of the sea to the visitors seated there.

Ramps and stairs as exhibition areas

The ramps and stairs of the tower are also used as exhibition areas, mainly for digital exhibits. Hanging points in the walls and ceilings are provided for other objects. The top two floors contain a library of analogue and digital books and a covered viewing platform. Rainwater falls through an opening in the ceiling into a small pool, where it is electrically circulated for exactly nine minutes every hour.

The library on the second highest floor opens in a semi-circle to the sea. © Jonathan Leijonhufvud

Concrete construction helps cool the building

Most of the rooms in the Sun Tower have an outdoor climate and are therefore neither heated nor cooled. The heavy concrete construction and effective cross-ventilation help to keep internal temperatures cool in summer. The supply air is pre-cooled in an underground duct, while the chimney effect created by the height of the building helps to ventilate the rooms.