A hydrogen-powered driverless cargo submarine that collects microplastics from the sea as it travels has been awarded almost £400,000 by the British government as part of a £23m ($31.8m) clean-shipping research and development competition that was dominated by H2-related technologies.

British start-up Oceanways and its R&D partners were awarded £385,842 to “investigate the feasibility of building and testing the prototype submarine powered by green hydrogen to financially de-risk the prototype submarine build”.

“The success criteria of this project will be understanding the technical & economic challenges and be ready with solutions & specifications to start the prototype build for an ideal trip from Glasgow to Belfast with one 20ft [shipping] container,” the grant application stated.

The Department for Transport also awarded a total of £754,115 to a London-based start-up aiming to build long-distance liquid-hydrogen-powered autonomous surface vessels capable of travelling at a speed of five knots (9.2km/h) for 70 days straight.

Possible uses for this technology include environmental monitoring and transferring crews to offshore wind farms.

Technology development company Steamology Motion and its R&D partners were awarded £164,488 for a feasibility study on an electric-propulsion vessel powered by a turbine driven by superheated steam produced by combusting hydrogen and oxygen.

Awards were also handed out to companies designing floating hydrogen production and storage barges; printed-circuit-board fuel cells; modular at-port green H2 generation; hydrogen fuel bunkering; hydrogen-electric powertrains with ceramic engines; ammonia fuel cells for shipping; retrofits of existing vessels for hydrogen propulsion; and fuel cells to provide on-board power for cruise ships.

“As a proud island nation built on our maritime prowess, it is only right that we lead by example when it comes to decarbonising the sector and building back greener,” said Transport Secretary Grant Shapps.

“The projects announced today showcase the best of British innovation, revolutionising existing technology and infrastructure to slash emissions, create jobs and get us another step closer to our decarbonisation targets.”