The world’s biggest cruise ship, Royal Caribbean’s “Icon of the Seas,” sets sail from Miami today, ushering in a new era of mega tourism on the high seas. But amidst the celebration, environmental groups raise a cautionary flag, voicing concerns about the vessel’s reliance on liquefied natural gas (LNG) as fuel and its potential contribution to harmful methane emissions.
This 8,000-passenger behemoth, spanning 20 decks, capitalizes on the booming cruise industry. However, its LNG-powered engines, while seemingly cleaner than traditional marine fuel, pose a new threat: methane leakage. This invisible culprit, though potent, fuels concerns about the ship’s long-term impact on our planet.
“It’s a step in the wrong direction,” declared Bryan Comer, Director of the Marine Program at the International Council on Clean Transportation. He estimates LNG emits “over 120% more life-cycle greenhouse gas emissions than marine gas oil,” highlighting the crucial role of methane reduction in climate mitigation efforts.
Methane’s warming power packs a punch. Over 20 years, it traps 80 times more heat than carbon dioxide, making its emission control paramount. Unfortunately, cruise ships like Icon of the Seas leak methane during engine combustion, a phenomenon known as “methane slip.” Industry experts claim low-pressure, dual-fuel engines used in cruise ships are particularly prone to this slip, raising the alarm for green groups.
Royal Caribbean maintains the “Icon” exceeds carbon emission regulations set by the International Maritime Organization (IMO) by 24%. Steve Esau, chief operating officer of Sea-LNG, an industry advocate, agrees that LNG emits less greenhouse gas than the VLSFO powering most shipping fleets. However, the challenge lies in maximizing fuel conversion within the engine cylinders. Juha Kytölä, R&D director at Wärtsilä, the engine manufacturer, emphasizes the importance of efficient conversion to minimize methane slip. He boasts a 90% reduction in methane emissions compared to their engines two decades ago.
Yet, research reveals a different picture. Studies funded by the ICCT and others estimate an average methane slip of 6.4% in cruise ship engines, significantly higher than the IMO’s assumed 3.5%. “Methane is under growing scrutiny,” says Anna Barford, a shipping campaigner at Stand Earth. The IMO’s commitment to addressing methane emissions in its greenhouse gas reduction efforts further underscores the environmental concerns surrounding LNG-powered vessels.
LNG’s future in the cruise industry remains debatable. While 63% of ships ordered between 2024 and 2028 are expected to be LNG-powered, the technology faces competition from alternatives like bio-LNG and traditional marine gas oil. Royal Caribbean itself embraces flexibility, aiming to adapt its fuel choices as the market evolves. “LNG is one piece of our strategy,” confirms Nick Rose, the company’s environmental, social, and governance vice president.
As the “Icon of the Seas” glides across the ocean, leaving a trail of luxury and wonder, it also leaves behind a cloud of questions and concerns about its environmental impact. The issue of methane emissions casts a shadow over the industry’s shiny, new vessels, urging a closer look at their true cost to the planet. Will LNG remain the fuel of choice, or will green alternatives pave the way for a more sustainable future for the cruise industry? Only time will tell.