An innovative structure capable of achieving 100 percent green energy consumption was unveiled on Sunday in Qingdao, Shandong province, making it the world's first ultra-zero carbon building, according to State broadcaster China Central Television.

The building goes beyond traditional green energy solutions by incorporating photovoltaic power generation, an energy storage system that uses retired power batteries and a vehicle-to-building power supply.

Standing 117 meters tall with 23 floors of office space, the building serves as the headquarters of Teld New Energy Co — one of China's leading electric vehicle charging operators. The building's east, west and south facades are fitted with integrated photovoltaic glass curtain walls that provide about 25 percent of the building's daily electricity use of roughly 6,000 kilowatt-hours, cutting carbon dioxide emissions by nearly 500 metric tons annually.

A specially designed power supply system allows the building to use direct current directly, avoiding losses typically caused by converting DC to alternating current.

At its base, the facility houses 14 retired electric vehicle batteries to address the intermittence of solar power. The storage system holds surplus photovoltaic energy as well as unconsumed clean grid energy during off-peak hours at the cost of 0.22 yuan per kWh for use during peak demand or cloudy days. It is equipped with a safety management system that automatically drops risky batteries into a water pool when a fire hazard is detected.

Zhao Yue, a researcher with the China Center for Information Industry Development, said the energy system establishes a new model for zero-carbon buildings by offering a viable way to recycle power batteries.

The broadcaster also reported that nearly 24,000 micro-sensors, equipped with facial recognition, enhance the building's digital system. The system activates lights and air conditioning when employees arrive and shuts them off when they leave, promoting conservation.

Yu Dexiang, chairman of Teld New Energy Co, said green electricity consumption alone reduces carbon dioxide emissions by 2,500 tons annually, while the digital system further improves energy efficiency and cuts costs by about 30 percent.

The building also features vehicle-to-building power supply technology.Robots automatically align electric vehicles in designated areas for parking and connect them to the power system, allowing them to supply electricity to the building.

Zhao said the smart energy management system can help the grid ease peak consumption and improve reliability.

"It possesses off-grid operational capability, ensuring an uninterrupted power supply for critical loads," he said.

houliqiang@chinadaily.com.cn