A Dutch consortium is on track to launch an innovative hydrogen fuel cell powered vessel in in 2021, writes Janny Kok.
Cryogenic hydrogen (which requires the cooling and storing hydrogen at -253 degrees C) or storing hydrogen under pressure are the two main alternatives under consideration, but “a third way”, binding hydrogen to a carrier substance, such as benzene, naphthalene, toluene or their derivatives, has also attracted interest.
By contrast, a fourth possibility, involving the chemical storage of hydrogen in chemical hydrides, has received less attention. Indifferent yields from the dehydrogenation of carriers had appeared to be an insuperable barrier to taking known reactions from the laboratory.
This changed when researchers in the Netherlands developed a technique that improved the proportion of hydrogen recovered from sodium borohydride (NaBH4). The white powder itself was well known, and as an ingredient in washing powder will be the least exotic hydrogen vector most readers can imagine. But by combining extremely clean water with a catalyst, researchers at TU Delft boosted the amount of hydrogen recovered above 95%.
The technology is being used as the basis of an Interreg North-West Europe project H2SHIPS to demonstrate the technical and economic feasibility of zero-emission hydrogen bunkering and propulsion for shipping.
The Port of Amsterdam Authority is part of the international consortium in one of the two pilot projects as part of H2SHIPS. It has put out a tender for a one of a kind hydrogen-powered port vessel, that will become a showpiece in the port of Amsterdam in 2021. The H2Ship project will involve the installation of a PEM fuel cell fuelled by a sodium borohydride storage system aboard a battery-electric 20 metre long vessel in the Port of Amsterdam in 2021.
The other H2SHIPS pilot project is the development and testing of an H2 refuelling system suitable for open sea operation in Belgium.
One of the professors involved in the project discussed the technology with The Motorship.
Assistant Professor Marine Engineering Klaas Visser at the Delft University of Technology said: “We will certainly meet the  deadline. At the moment, we are busy with the detailed design of the ship to be built.”
Visser identified several key advantages associated with the technology, including a potentially higher energy storage density (38.5 MJ/kg), similar to that of diesel fuel. The certification process would also be somewhat more straightforward. While the material was flammable, it was slow burning, by contrast with some other forms of hydrogen.
Storage of the powder carrier aboard the vessel was much less space consuming than compressed hydrogen storage. Based on a 250 kW PEM fuel cell, 5m3 of sodium borohydride could provide enough fuel for 70 hours of operation.
One of the main focuses of the research was identifying processes for storing or using the residual product (NaBO2) produced after hydrogen was produced from the NaBH4. Developing a green hydrogen solution that required the vessel to discharge a tank at the end of the journey would not be “sustainable”, Visser noted.
A consortium including Tata Steel, the University of Amsterdam, and the TU Delft Faculty Mechanical, Marine, and Materials Engineering was launched to find uses for the NaBO2 (also called sodium borohydride) in March 2020, Visser noted.
A ship powered by hydrogen released from sodium borohydride could discharge the residual product at a processing plant, which would process it into hydrogen for new use.
“That is why one has to think about alternative energy for the transition into zero-emission fuels when doing research and development. We have found that in the concept for sodium borohydride and the onboard hydrogen storage. The result is a circular produced fuel, with natural components,” Visser noted.
The research project has attracted interest from companies in the shortsea, fisheries, dredging, and ferry sectors. The development of a modular hydrogen power pack with sodium borohydride was scheduled for 2021, before the recent coronavirus pandemic.
Another project that is under consideration was the retrofit conversion of a larger inland commercial vessel, altering one of its propeller shafts to operate on a PEM fuel cell powered by sodium borohydride fuel.
The projects formed only part of wider commercial and public-private research into hydrogen fuel and the corresponding supply chain and infrastructure in the Netherlands.
Recently the Port of Rotterdam Authority, Shell Nederland, and Dutch energy supplier Eneco joined forces to set up a green 150-250 MW electrolyser plant at the port extension Tweede Maasvlakte. The produced hydrogen is to be transported through a new pipeline to Shell’s refinery in the port area.
Visser welcomed the upsurge of interest in environmentally sustainable solutions. “We should embrace every demonstrator project. Besides, the Netherlands is a small country in which everybody in the field knows each other. All of these fields come together at TU Delft.”