A Chinese company has built the world's first megawatt-level seawater electrolyzer for hydrogen production, paving the way for new offshore energy development.

The device successfully completed a test run, according to a report in the domestic newspaper Science and Technology Daily published Friday. The newspaper hailed the technology as a "key breakthrough" for its developer, the China National Offshore Oil Corporation (CNOOC).

The electrolyzer's core components fit within five shipping containers, facilitating deployment at sea, according to CNOOC engineer Li Zhichuan. "It can produce 200 normal cubic meters of hydrogen per hour with a purity of 99.999 percent."

The system is designed to utilize surplus electricity generated by offshore wind and solar farms. "Seawater electrolysis offers advantages over traditional freshwater electrolysis," Li explained. "Seawater is abundant."

However, seawater electrolyzers are more susceptible to damage due to seawater's complex composition. Li's team developed an innovative solution that allows raw seawater to be fed directly into the electrolyzer without prior purification, enabling stable and cost-effective operation.

A CNOOC manager said the technology has the potential to establish a new model for green hydrogen-based energy consumption at sea.