Three years after the initial announcement, the world’s first hydrogen-powered tugboat, baptized appositely ‘Hydrotug 1’, has arrived at its workstation in the Antwerp Port to start its real-world testing from mid-January. It features BeHydro V12 dual fuel medium speed engines, each providing 2 megawatts, that can run on hydrogen or diesel fuel.

The idea is to make it a zero-emission vessel for 65 to 80% of the time, but if there is no hydrogen supply – like a breakdown at the pumps – it can easily switch to ‘normal’ diesel fuel to keep on working. The question is whether Antwerp Port won’t be tempted to use more diesel than hydrogen for the time being, as hydrogen prices are highly volatile, sometimes up to nearly €20/kg.

Avoiding emissions of 350 cars

When mainly using ‘grey’ hydrogen for the time being, the Hydrotug 1 will avoid the equivalent of the emissions of 350 cars per year. Running on diesel, the motors with particular after-treatment comply with the EU standard on particulate emissions, Stage V, for non-road mobile machinery (NRMM) dating back to 2016.

The Antwerp Port commissioned the development of the ‘Hydrotug’ to the Belgian shipping group Compagnie Maritime Belge (CMB), which already pioneered a hydrogen ferry shuttle for its personnel in the harbor at the end of 2017. By making its fleet of tug boats ‘eco-friendly’ in the future, the Port of Antwerp wants to make a step to become a carbon-neutral harbor by 2050.

“Port of Antwerp-Bruges aims to develop its potential to the full, committing itself as an active pioneer in the hydrogen economy on a European scale,” says Jacques Vandermeiren, the CEO of Port of Antwerp-Bruges “The ecosystem represented by the port platform is an ideal testbed for this technology on a large scale. In this way, we seek to be a source of inspiration and to set an example for other ports.”

CMB-Tech development

The technology for Hydrotug 1 was developed by CMB’s green-tech engineering daughter, CMB-Tech, and Ghent-based marine engine and genset expert ABC (Anglo Belgian Corporation). Since 1912, ABC has built a range of marine engines for river barges up to coastal freighters and tugs. The latter typically uses two motors to provide enough power for towing ships.

Under its CEO Alexander Saverys, who is a vivid advocate of hydrogen as a sustainable fuel for the maritime sector, the CMB daughter has already pioneered several H2 projects. Japan’s first passenger ferry on hydrogen for commercial use was officially launched in August 2021 in a joint venture with Japanese shipbuilding and shipping firm Tsuneishi.

Closer to home, with its Dutch-British sister company Windcat Workboats, CMB-Tech presented the 25-meter-long HydroCat 48, the world’s first hydrogen-powered crew transfer vessel (CTV) of this size. Two MAN diesel engines propel the Hydrocat 48 retrofitted for dual-fuel use by CMB-Tech with a hydrogen injection system and deliver 1 498 kW of power.

415 kg of hydrogen stored on the deck

The Hydrotug 1 can store 415 kg of compressed hydrogen in six stillages installed on the deck and eliminates – when running on hydrogen – the emission equivalent of 350 cars per year.

Hydrogen can be refueled at CMB’s public multimodal hydrogen station for ships and road transport near the Port House on the Antwerp Eilandje, inaugurated in June 2021. That station is also equipped to supply mobile filling stations that can serve vehicles or vessels elsewhere in the port area.

Most hydrogen the Hydrotug 1 will use will be the cheaper ‘grey’ variant, produced as a by-product from the chemical industry in Antwerp from gas. But in that process, quite a lot of CO2 is still emitted. Green hydrogen is made in limited quantities at the CMB station with solar energy and electrolysis.

Refueling at offshore wind parks?

Alexander Savereys told local press at the launch of the tug that he is “dreaming” of being able in the future to tank ‘green’ hydrogen at wind parks at sea, made with excess energy. But in Namibia, for instance, CMB.TECH is already building Africa’s first public filling station with large on-site green hydrogen production.

The site in Walvis Bay uses solar energy to make the hydrogen. Its strategic location should provide direct access to major shipping routes. The company says the facility will supply hydrogen to trucks, ships, and railway applications.