HANGZHOU — The National Food and Strategic Reserves Administration has announced plans to expand its green grain storage network to 100 model granaries by 2027, covering all seven of China's major ecological zones.

Speaking at a national conference in Hangzhou, capital of East China's Zhejiang province, in late April, officials showcased a suite of smart technologies — from kernel-scanning artificial intelligence to autonomous leveling robots — designed to keep grain loss rates below 1 percent as China enters its second consecutive year of 700 million metric tons in output.

China, the world's largest grain producer, harvested a record 714.88 million tons in 2025, according to the National Bureau of Statistics.

Despite the bumper harvests, the country maintains a tight long-term supply-demand balance. Boosting storage technology has thus become a strategic lever for ensuring food security.

To this end, the green grain storage integration and demonstration program was launched in 2025, with an initial batch of 30 pilot sites rolling out nationwide.

This strategy is already paying off. According to the NFSRA, China has over 730 million tons of standard warehouse capacity, of which 220 million tons are equipped for low-temperature and quasi-low-temperature storage, and more than 55 million tons use controlled-atmosphere technology. The comprehensive loss rate during a full storage cycle has been kept under 1 percent.

At a grain depot in Renhe, Zhejiang, a suite of technologies is already in use.

"The reading right now shows 19 C and 65 percent humidity inside, well within the technical standards for quasi-low-temperature grain storage," said Wan Xiaojin, director of the depot, pointing to a thermo-hygrometer on the warehouse wall.

A key enabler of that stable climate is an air-supported membrane silo, the likes of which are being rolled out across multiple regions. Depot staff affectionately describe it as a giant "breathing white chubby" — a playful nickname for the plump, dome-shaped structure.

The secret lies in three layers of technology embedded in the roof, the grain pile and the walls: solar shielding, active cooling and energy efficiency, working together so the grain "sleeps in a good house", said Wang Hongli, chief technician to manage the membrane silos.

Before entering the warehouse, every batch of grain passes through an intelligent inspection gate equipped with high-precision detectors — essentially a CT scanner for kernels.

Five images are taken of each individual maize kernel from five different angles, ensuring that there are no blind spots in the quality inspection. For a standard 100-gram maize sample, the entire scan takes less than 100 seconds, said Wang Liangliang, a technician of the grain smart check team.

Grain ships operating on the Grand Canal, the world's longest artificial waterway stretching from Beijing to Hangzhou, use pipes to funnel grain into their holds.

"The entire assembly line operates through sealed pipelines," said Ma Guojun, head of the storage and transport section at the depot."Our operation won't be affected no matter how the weather changes."

Flattening the grain pile on the barges used to mean sending workers several meters down into the mass to shovel it level by hand. Now the job falls to a second-generation "leveling robot", which can operate autonomously for around eight hours on a single charge.

These technologies form part of a nationally orchestrated push to build a cohesive green storage system resting on five pillars: upgrading warehouse performance enabling clean and efficient grain handling; deploying intelligent monitoring and early warning; applying green pest and mold control; and rigorously evaluating all measures against scientific benchmarks.

Zhang Zhongjie, chief researcher at the NFSRA academy, said that by pursuing green, intelligent and integrated development, China is building safe, green and smart granaries to ensure that "every single grain stays fresh".

Xinhua