Chinese scientists have created a floating hydrogen farm that harnesses both the power of the winds and the seas to convert seawater into clean hydrogen gas, without the need for the often energy-intensive desalination process typical in the industry.
The offshore platform, dubbed ‘Dongfu Number One’ by its creators, completed a successful 10-day continuous operation trial upon its working debut in May, according to a June report from state-run news agency Xinhua.
Anchored off of the Fujian coastline in the country’s mountainous southeast, Dongfu Number One measures an estimated 63 square metres.
The platform, developed by the Dongfeng Electric Corporation in collaboration with the University of Shenzhen researcher, Xie Heping, combines hydrogen production through electrolysis with a steady offshore wind power supply system.
The resulting product is a renewable-powered device that converts one of the world’s most abundant resources, seawater, into hydrogen gas without impacting the environment significantly.
Using seawater in place of freshwater during the electrolysis process brought about several challenges to Xie and his colleagues.
Seawater is full of microorganisms and fine substances, such as sand, salt, microplastics and other suspended particle materials and these impediments can affect electrolysis efficiency as well as damage some of the device’s more critical components.
The methods for hydrogen production from seawater call for a process whereby seawater is first desalinated and filtered before undergoing electrolysis.
Industrial-scale desalination is an energy and resource-intensive task. Spent membranes used to filter out undesirable substances are often saturated with dangerous levels of salt and other potentially toxic chemicals, making them expensive to dispose of safely.
Dongfu Number One’s 10-megawatt wind turbine supplies a 28-kilowatt battery and, according to its makers, is resilient enough to withstand gusts of wind up to level 8 on the Beaufort Scale (roughly 62 kilometres per hour).
Xie’s work is based on his November 2022 academic paper detailing the hydrogen production technology now used in Dongfu Number One.
The research, published in the peer-reviewed scientific journal, Nature, was celebrated by the Chinese Ministry of Science and Technology and recognised as one of the country’s top 10 advancements for the year, according to the South China Morning Post.
After being subjected to ten days of non-stop hydrogen production, the team found Dongfu maintained an ion-rejection rate and hydrogen purity score of at least 99.9 per cent, matching pre-trial laboratory results.
The platform can produce hydrogen at roughly $1.57 per kilogram compared to the current market rate which can float anywhere between $3 and $6 dollars per kilogram, according to the United States Department of Energy.
Xie told the media that his next step was to further improve the platform’s hydrogen production efficiency before scaling up capacity by opening discussions with global energy firms.
https://interestingengineering.com/science/hydrogen-from-seawater-without-desalination
