Royal Caribbean Cruises Ltd. (RCL) recently announced that the newest class of ships will be powered by LNG and introduce the use of fuel cell technology, ushering in a new era of shipbuilding that is expected to significantly reduce greenhouse-gas emissions.

RCL said that it has signed a memorandum of understanding with shipbuilder Meyer Turku for the new class of vessels under the project name “Icon,” The vessels will be delivered in the second quarters of 2022 and 2024, according to RCL.

In the meantime, the company said, it will begin testing fuel cell technology on an existing Oasis-class ship in 2017, and will also run progressively larger fuel cell projects on new Quantum-class vessels being built in the next several years.

RCL is already known for making steady progress on energy efficiency and reduced emissions through such technologies as air lubrication, which sends billions of microscopic bubbles along the hull of a ship to reduce friction, and advanced emission purification scrubbers, which clean exhaust gases before they leave the ship.

Use of the new technologies “will result in much cleaner emissions, as they produce no sulfur and significantly reduce the production of nitrogen oxides and particulates,” RCL said in a statement.

“With Icon class, we move further in the journey to take the smoke out of our smokestacks,” Richard Fain, chairman and CEO of RCL, said. “We are dedicated to innovation, continuous improvement and environmental responsibility, and Icon gives us the opportunity to deliver against all three of these pillars.”

The switch to LNG provides further momentum for the technology, which has begun making significant inroads in the maritime industry.

“Increasing the commitment to LNG makes it easier for suppliers to make their own infrastructure commitments,” Fain explained. “As more ships are built for LNG, the number of ports that support it will grow.”

The Icon ships are expected to run primarily on LNG, but will also be able to run on distillate fuel to accommodate occasional itineraries that call on ports without LNG infrastructure, according to RCL.

The introduction of fuel cells represents another dramatic step forward for the maritime industry, which has only made limited experiments using the technology.

“We believe fuel cells offer very interesting design possibilities,” said Harri Kulovaara, RCL’s chief of ship design.

“As the technology becomes smaller and more efficient, fuel cells become more viable in a significant way to power the ship’s hotel functions. We will begin testing those possibilities as soon as we can and look to maximize their use when Icon class debuts,” Kulovaara noted.

Kulovaara said RCL had been eyeing fuel cells for nearly a decade and believes the technology is now at a stage of development that justifies investment.

“There is a long lead time for Icon class, and we will use that time to work with Meyer Turku to adapt fuel cell technology for maritime use,” he said.

Kulovaara further noted that additional regulatory standards would also need to be developed for the technology.

Because of the long lead time, Kulovaara said that many Icon design elements are in early stages. The Icon ships would likely accommodate around 5,000 passengers, he said, but details are still being worked out.

Icon is the first new ship class announced by RCL since Celebrity Cruises’ Edge class, which debuts in 2018. The company is also expanding its fleet with new Oasis- and Quantum-class ships for RCL. Fain said the new ships are in line with RCL’s strategy of moderate capacity growth.

The order is contingent upon the completion of contractual conditions, including documentation and financing, according to RCL. Final contracts are expected to be completed by year-end.

Based upon current ship orders, projected capex for full-year 2016, 2017, 2018, 2019 and 2020 are $2.4 billion, $500 million, $2.6 billion, $1.5 billion and $2 billion, respectively.

Capacity increases for 2016 through 2020 remain unchanged and do not include potential ship sales or additions that the company may elect to make in the future, according to RCL.

Bryan Sims can be reached at bsims@hartenergy.com and @bsimshart.