Cruises – Ship Ahoy

Author: Achim Geiger

Aug 16, 2023

Large cruise ships are basically floating towns. They have their own self-sufficient infrastructure at sea – and a bunch of problems in port when the time comes for passengers to go ashore. But how can the climate and environmental footprints of these large ships be improved? Technical solutions are necessary.

When steamship “Augusta Victoria” set sail from Cuxhaven to the Mediterranean on January 22, 1891, for the first cruise in history, nobody even thought about environmental protection or climate change. Cruisers of the early days simply wanted to enjoy their vacation, have their every wish catered to by the crew, enjoy good food, and have lots of fun. At least in this respect, times have not changed, even if the activity program on board is broader than it was back then, with a climbing area, slides, miniature golf, go-kart track, bumper cars, and skydiving simulator. Tourism researcher Alexis Papathanassis from the Chair of Tourism and Maritime Tourism at Bremerhaven University of Applied Sciences defines a cruise vacation as combining the richness of experience of a round trip, the comfort and amenities of a hotel, and the entertainment options of a vacation destination in one package.
The largest cruise ship in the world is five times larger than the Titanic
In fact, demand for such packages is high. The Cruise Lines International Association (CLIA) expects bookings to rise by around twelve percent in 2024 compared ro the record year of 2019, when 30 million passengers sailed the seven seas. Shipyards are well prepared for the boom. In the last five years alone, some 15 ocean giants have been launched, such as “Wonder of the Seas”, “Costa Smeralda”, “MSC World Europa”, “Aida Cosma”, and “Carnival Celebration”, all of which can take well over 6,000 passengers. The designated front-runner for the title of “World’s Largest Cruise Ship” is the “Icon of the Seas”, which is scheduled for launch in early 2024 – an ocean liner five times larger than the Titanic.
Does the cruise industry prefer superlatives to environmental protection?
However, the cruise industry’s penchant for superlatives does not go down well with environmentalists. Venice has already banned cruise ships from the city center, and Barcelona, Marseille, and Amsterdam are also planning restrictions. The 2023 cruise ranking of the German Nature Conservation Association (NABU) indicates why these big ships have such a bad image. Heavy oil fuels the engines of around half the 300 ships in the global cruise fleet. Marine fuel is cheap, but it is responsible for emissions of sulfur oxide, nitrogen oxide, particulate matter, and soot. An alternative would be to switch to marine diesel, using diesel particulate filters and catalytic converters to minimize air pollutants. Even then, the problem of greenhouse gases remains: According to the Federal Environment Agency, a seven day cruise produces up to 1.9 tons of CO2 per person. And the emissions do not necessarily occur on the cruise itself. Cruise ships spend around 40 percent of their time in port. The onboard supply for hotel operations, catering, and air conditioning obviously continues. The CLIA estimates that between six and ten percent of a cruise ship’s total carbon dioxide emissions are due to the time spent in port.
Cruise ships blamed for climate-damaging emissions
So do cruise ships deserve the blame for climate-damaging emissions? The question requires consideration. One approach is offered by a study presented earlier this year by the Bremerhaven University of Applied Sciences, which examines the research situation on the impact of cruise tourism on coastal areas over the past ten years. The study shows that the cruise business is not just made up of cruise companies, but a network of institutional and business players who decide what contribution they make in terms of sustainability. For example, one sensible solution for layovers in port would be to power a ship with green shore power. Around 40 percent of the global fleet is equipped with the necessary connectors. However, only two percent of all ports have at least one berth with a plug-in opportunity. So are technical solutions the ideal solution in terms of cruise ship propulsion, energy efficiency, and economy? Surprisingly, the sciences are not considering this possibility, as the Bremerhaven study shows – it says that sustainable technologies are the least researched aspects of cruise tourism.
Shipping company MSC Cruises succeeds in first almost climate neutral voyage
So who will address sustainability on the world’s oceans? Ultimately, this is the shipping companies’ responsibility. When it comes to propulsion, they are now relying on dual fuel engines designed to run on liquefied natural gas (LNG) and marine diesel. Almost a dozen of the cruise ships that have been launched since 2018 already have this technology on board. The credit for the first almost carbon neutral voyage goes to Italian shipping company MSC Cruises. The “MSC Euribia” has LNG propulsion on board, which can be operated with renewable fuels. For the transfer voyage at the beginning of June 2023 from the shipyard in St. Nazaire, France, to Copenhagen, the shipping company bunkered around 400 tons of bio-LNG, with which the ship has achieved a successful climate balance. The bottom line is that LNG is a bridging technology for the cruise industry. It not only reduces pollutant emissions, but also improves the greenhouse gas balance by up to 20 percent compared to conventional ships. However, when it comes to methane loss, opinions are once again divided. After all, unburned methane, which has a much greater impact on the climate than CO2, always escapes during the production, transportation, and combustion of LNG. There is therefore a risk that saved CO2 emissions are overcompensated by methane emissions.
The ship concept of the future combines combustion engine with electric drive
And where might the technological path lead in the long run? In March 2023, the Royal Caribbean Group launched a research project in which the combination of a fuel cell system with a high performance battery system will make it possible to operate the entire hotel load of a cruise ship without pollutants while in port. The plan also includes the use of shore power and batteries to operate the cruise ships. In addition, there are new marine fuels such as bio fuels and synthetic fuels. Incidentally, a true pioneer of sustainability comes from Norway. The “MS Roald Amundsen” of the Hurtigruten shipping company is a cruise ship with hybrid technology designed for travel in polar waters. The propulsion concept combines an internal combustion engine running on diesel oil and an electric drive along with a generously dimensioned battery pack. The ship could thus travel for 45 to 60 minutes on purely electric power. In regular operation, the drive is expected to reduce fuel consumption and CO2 emissions by approximately 20 percent.