Chongqing - To achieve the national goal of peak carbon emissions by 2030, Southwest China's Chongqing will promote ultra-low energy consumption buildings this year, according to the Chongqing Municipal Commission of Housing and Urban-Rural Development.

With the rapid increase in building area and living quality, building energy consumption continues to rise. The survey reveals that nearly 50% of the country's carbon emissions come from the whole life cycle energy consumption of buildings. The ultra-low energy consumption building is the future of energy saving and emission reduction in construction. 

Building's airtightness

With rich water resources, temperature, and quality, Chongqing boasts unique edges of renewable energy resources for the river water source heat pump, facilitating the creation of ultra-low energy consumption buildings, said an official of the Chongqing Municipal Commission of Housing and Urban-Rural Development.

Data shows Chongqing has more than 800 green and energy-saving building materials companies, forming an industrial cluster with an annual output value of about 40 billion yuan (about 5.8 billion U.S. dollars). 

Yuelai Art Museum. (Photo/Liangjiang New Area)

Located in the Liangjiang New Area, Yuelai Art Museum is a shining example that utilizes triple-layer insulating glass and other facilities to strengthen the building's airtightness. 

Airtight buildings are more comfortable, efficient, and less likely to cause health problems for occupants than drafty structures. Achieving airtightness, resistance to unintentional airflows directed both in and out of a building, is essential for any architect that wants to maximize building performance.

The airtightness significantly impacts the energy consumption of heating and air conditioning. Therefore, hundreds of thermally dimmable glass are installed in the building dome of the Yuelai Art Museum, which can automatically switch between transparent and frosted glass according to the intensity of sunlight to reduce solar radiation. 

Completed in 2019, Yuelai Art Museum fills the gap in Chongqing's near-zero energy consumption and carbon buildings with an energy-saving rate and a carbon reduction rate of over 90%. 

Performance-based design

According to the plan, each district and county in Chongqing will launch at least one pilot ultra-low-energy building project this year. However, high construction costs and complicated technology are two big problems in developing ultra-low energy consumption buildings. 

Ding Yong, a professor at Chongqing University, explains that ultra-low-energy buildings have to abandon the traditional benchmarking design and emphasize performance-based design to match geographical conditions, climate resources, and application performance. 

Ding pointed out that ultra-low energy consumption buildings are still in their infancy in China, but it is also worth learning from the experience of some big cities like Shanghai and Shenzhen. 

For example, Chongqing could refer to Shanghai to focus on scientific research efforts and strengthen the project's landing. Meanwhile, upgrading supporting industries and introducing more cost-effective products to reduce costs is necessary.