cruise ship
Getty Images/Marco BELLO

The largest cruise ship in the world that embarks on its first commercial voyage from Miami has been accused by experts of greenwashing, as their use of liquified natural gas might lead to increased methane emissions.

Icon Of The Seas

The Icon of the Seas is longer than the Eiffel Tower, stands 20 decks above the waters, and can hold more than 7,000 passengers and staff. It weighs a quarter of a million gross tons, enough to swallow five Titanics.

The president of Royal Caribbean, Jason Liberty, said that it is the "biggest, baddest ship on the planet" and that it rapidly became known on social media as "human lasagne."

However, the introduction of the massive ship in Florida, one of many of the same size or larger that could be built in the coming years, has refocused attention on the environmental impact of cruise travel.

Several studies conducted by environmental organizations found that a week-long vacation on a European cruise was up to eight times more carbon-intensive than flying and staying in a hotel.

The Icon of the Seas has six dual-fuel engines that can run on liquefied natural gas (LNG), a fuel option that minimizes sulfur and greenhouse gas emissions, according to the Cruise Lines International Association. However, environmentalists are concerned that LNG-powered ships will contribute to increased methane emissions.

Furthermore, others say that cruise passengers emit eight times more carbon than those who take land-based holidays. Royal Caribbean asserts that energy efficiency and emission reductions are closely monitored for every kilowatt utilized on the Icon of the Seas.

Bryan Comer, director of the International Council on Clean Transportation's marine program, claims that utilizing such fuel demonstrates an industry "investing in false climate solutions."

"They are doubling down by calling LNG a green fuel when the engine is emitting 70 to 80% more greenhouse gas emissions per trip than if it used regular marine fuel. Icon has the largest LNG tanks ever installed in a ship. It is greenwashing," he added.

Use Of LNG

Using LNG instead of other marine fuels reduces carbon dioxide (CO2) emissions by quarter. However, Comer stated that a cruise ship employing LNG releases greater greenhouse gas emissions overall due to phenomenon known as "methane slip".

This is where some gas is not burnt, resulting in methane emissions, which are significantly more potent than carbon dioxide. During the 20 years following its release into the atmosphere, methane traps approximately 80 times more heat than CO2.

He recommended that ships employ fuel cells and renewable hydrogen or methanol, both of which create fewer greenhouse gasses.

The ship's parabolic bow, a first for Royal Caribbean, is intended to assist the ship travel more easily through the water while also reducing fuel usage and emissions, according to Comer, who adds that it also benefits the cruise line's bottom line.

The ship generates more than 93% of its fresh water through reverse osmosis. Icon of the Seas also boasts the brand's first microwave-assisted pyrolysis waste-to-energy system (MAP), which converts onboard garbage into gas that the ship may use for energy.