Students at TU Eindhoven find safe way to store hydrogen using iron pellets

A team of students at TU Eindhoven has developed a way to safely store and transport hydrogen. To do this, the SOLID team uses small iron pellets that can store the energy of the hydrogen. After transport, the iron can be converted back into hydrogen and iron oxide when in contact with steam. The students have built an experimental setup, the so-called Steam Iron Reactor One (SIR One), with which tests will be carried out in the near future, according to the press release.

The team calls the cycle a kind of "sustainable hydrogen battery." Normally, hydrogen is stored in tanks. Because of iron's higher energy density, more energy can be stored in the iron pellets. The students refer to this as the "ideal form of storage."

This type of energy storage of hydrogen can help with the energy transition, according to the students. Currently, "clogged power grids and limited storage options" are still a major obstacle. The Dutch government is already betting heavily on hydrogen. For example, the government is allocating 800 million euros for a number of large hydrogen projects, it was written in the press release. "Subsidies from the Dutch government go mainly to the production of hydrogen," the students note. "But what about storage and distribution?"

The team also points out that iron pellets are much safer than transporting bulk hydrogen. "Therefore, the safety regulations for iron are also less stringent than for hydrogen," says SOLID's Timme Ter Horst. In addition, this technique is cheaper, the students say.

Professor Richard van de Sanden says the technique is not entirely new, but rather "coming back." SOLID will continue its work in the coming years and hopes to demonstrate the system in the port of Rotterdam in 2027.