Carnival (CCL 0.43%) (CUK 0.63%) took delivery of its newest, most innovative cruise ship, the Mardi Gras, on Friday. The Mardi Gras is a liquified natural gas (LNG) powered ship, the first of its kind in North America, and is part of the cruise line operator's decarbonization program.

Scheduled to make its inaugural voyage on April 24, 2021, the Mardi Gras features another first for a cruise ship: an at-sea rollercoaster.

Artist rendition of BOLT roller coaster

Artist rendition of the cruise industry's first at-sea roller coaster, the BOLT. Image source: Carnival.

Cruising to a greener future

LNG is a fast-growing option for a cruise industry wanting to switch from heavy fuel oil diesel engines and marine gas oil for gas turbine engines.

Carnival was one of the very first cruise ship operators to make the switch, using LNG in 2015 to supply its AIDA Cruises' AIDAsol while in port. Three years later it launched the AIDAnova, the first cruise ship anywhere that could be powered at sea or in port by LNG. It followed with the Costa Smeralda in 2019.

The Mardi Gras will be the first LNG-powered vessel to ply the waters around the southeastern coast of the U.S. The Carnival Celebration will follow in 2022.

LNG ships are not especially common yet because there have been few LNG refueling ports available. Carnival has partnered with Royal Dutch Shell (RDS.A) (RDS.B) to use the oil giant's LNG bunker barge that will let cruise ships like the Mardi Gras refuel while they are in port.

Carnival worked with Port Canaveral in Florida to build an Excel-class port to handle ships of the size of the Mardi Gras. The new 180,000 gross ton vessel can accommodate 5,200 guests and 2,000 crew. It features 2,600 staterooms and 180 suites, and will also have the world's first roller coaster, the BOLT, that will operate while at sea.