Viking Cruises is working on a liquid hydrogen-fueled cruise ship, according to the Norwegian Maritime Authority (NMA).

Plans were unveiled by Viking Cruises’ Project Manager Serge Fossat at the NMA’s Safety at Sea conference in Haugesund on Friday, Sept. 29.

While few details were released, it is assumed that the liquid hydrogen would be used in fuel cells, although that technology is said to be several years away from practical application aboard cruise ships, according to industry sources.

Viking is reportedly in talks with the Norwegian state-controlled oil producer and distributor Statoil for a possible bunkering solution.

In a prepared statement, NMA Director Olav Akselsen described the plans as very exciting, possibly leading to a zero-emissions powerplant.

In the same statement, Viking’s CEO Torstein Hagen said he wants to lead the development toward zero emissions, although admitting that it will take time to get there.

Challenges include keeping the hydrogen liquid at 423.17 degrees Fahrenheit. It is also highly explosive.

Liquid hydrogen has commonly been used as rocket fuel by NASA. It can also be used as fuel for combustion engines or fuel cells.