Underground hydrogen station design cuts explosion risk by 50%, researchers say

South Korean researchers have developed a technology that places high-pressure equipment at hydrogen charging stations underground, significantly reducing explosion risk while improving space efficiency.

The Korea Institute of Civil Engineering and Building Technology announced Friday it had developed an above-below-ground integrated protection structure safety design technology that positions key high-pressure equipment for urban hydrogen production and charging facilities in underground protective spaces and connects them to above-ground operating facilities.

Hydrogen charging stations and other urban hydrogen facilities are essential infrastructure for expanding the use of hydrogen buses and commercial vehicles. However, the high-pressure nature of hydrogen handling makes safety a critical concern, and securing sufficient site space in urban areas poses an additional challenge.

The core of the newly developed technology is placing key high-pressure equipment — including hydrogen compression and storage systems — underground. It integrates leak detection, accident shutoff, ventilation, blast damage mitigation and real-time safety management into a single system built on existing hydrogen facility underground technology.

The research team established a three-stage safety framework covering accident prevention, damage reduction and real-time response.

When hydrogen leaks, sensors detect it early and automatically shut off valves while halting related equipment. At the same time, a forced ventilation system activates to prevent hydrogen from accumulating inside the facility.

In the event of a fire or explosion, the ground, underground structures and dedicated protective installations work together to suppress blast impact and contain debris. The system is also designed to vent explosive pressure in a safe direction, minimizing the effect on surrounding facilities and residents.

The research team verified the technology's safety through large-scale numerical analysis and actual hydrogen leak, fire and explosion experiments. Applying the blast pressure reduction and protection technology was found to lower the overall facility risk — including structural destruction and debris generation — by more than 50 percent.

The institute has moved beyond technology development to pursue real-world application. It is currently advancing detailed design of a test bed in Pyeongtaek and building demonstration equipment, while also designing an integrated safety management platform capable of monitoring facility conditions in real time.

Going forward, the team plans to conduct long-term operation to comprehensively verify hydrogen leak and ventilation performance under seasonal temperature and humidity changes, as well as structural vibration, equipment failure and maintenance accessibility, and to gather actual operational data.

Park Seon-gyu, president of the Korea Institute of Civil Engineering and Building Technology, said the technology simultaneously addresses safety and space efficiency for urban hydrogen facilities, calling it "a core foundation supporting the expansion of hydrogen buses and commercial vehicles and the transition to an eco-friendly transportation system." He added that the institute would "realize hydrogen city infrastructure that the public can trust through field demonstration and institutionalization."