Beijing-based firm OPEN Architecture has revealed the design of its under-construction Sun Tower project located in Yantai, China, a city along the coast of the Yellow Sea. 

The tower, the recipient of the Jeu d’Esprit Special Prize of AR Future Project Awards 2021, comprises a semi-outdoor theater, a winding exhibition space, and a library in the sky. The structure also features a unique semi-outdoor space at the top, called a “phenomena space,” that allows visitors to observe natural phenomena throughout the year.

The city of Yantai wanted to create a landmark on the coast as a symbol of its rapid development and status as an industrial powerhouse in China. The name Yantai means “Beacon Tower,” derived from the series of watchtowers built during the Ming Dynasty to warn against impending attacks on the coastline. OPEN’s response to the design brief was to establish a purposeful structure that connected to this history and evoked the ancient rituals of nature worship while providing needed cultural facilities in the newly urbanized district. Yantai is also noted for its spectacular views of the sunrise across the Yellow Sea, which is something the architects wanted to embrace in the design. 

The form of the 164-foot tower is a large curvilinear structure. Sitting in a gently sloped plaza, two layers of slanted white concrete shells are connected and braced by horizontal slabs and ramps. Its shape was designed according to studies of the sunlight. Apertures around the building invite light into the interiors while providing views of the sea. OPEN worked closely with engineering firm Arup to achieve this complex design. 

The concave inner shell of the Sun Tower acts as a sound collector, absorbing and amplifying the sounds from the sea. The smaller upside-down upper shell houses the light-filled library and the “phenomena space” equipped with views of the ocean and the sky. An oculus in the center of the phenomena space’s ceiling allows rainwater to enter and fill a small pool underneath in the summer. In the winter, the pool will be dry and used as a fireplace. 

OPEN worked with French firm dUCKS scéno to conceive exhibition spaces with a focus on digital exhibitions and big data technologies. The design team also worked with Aric Chen, the current General and Artistic Director of Het Nieuwe Instituut in Rotterdam, who consulted on the project from a curatorial perspective. 

At the base of the tower lies the plaza containing a shallow pool that features misting devices and spouting fountains. A specially designed water channel cuts across the plaza, serving as the straight line that the shadow of the Sun Tower will follow on the day of the equinox. A series of elliptical rings are set in the pavement pattern. The intersections between the rings and the water channel will mark the building shadow’s footprint at specific hours on the equinox day. At one of the outer rings, a series of fountains were designed to celebrate the 24 Solar Terms of the Traditional Chinese Calendar. 

“Today it's so important to find ways to connect and embrace nature, we wanted to keep this central to the concept of the Sun Tower and pay respect to the power of the surrounding landscape,” said OPEN founding patterns Li Hu and Huang Wenjing. “Immediately when we conceived of the design, we wanted to reference ancient human rituals, honoring the sun, moon, and stars, and offering a space for reflection and contemplation. On the other hand, we also wanted to ensure the building had an authentic purpose and function, something that would be of benefit to the citizens of Yantai rather than just a folly on the beach. Creating spaces that juxtapose the incredible ocean views with the forward-thinking digital exhibitions that explore nature.” 

Sun Tower is expected to open in 2024 and will be featured in OPEN’s forthcoming book Reinventing Cultural Architecture: A Radical Vision by OPEN published by Rizzoli in April 2022.