As major players in the travel industry, cruise lines have a responsibility to not only operate sustainably, but also lead global efforts for the future from the forefront of maritime innovation.
The latest sustainability report from the Cruise Lines International Association (CLIA) outlines the ways in which the cruise industry is moving towards a more sustainable future and how it plans to achieve net-zero emissions by 2050.
AdvertisingWidely ratified treaties such as MARPOL (the International Convention for the Prevention of Pollution from Ships) have reduced greenhouse gases worldwide, but CLIA members are committed to going beyond MARPOL requirements, and introducing new technologies and practices that will allow them to do so. To reduce carbon emissions by 40 percent by 2030.
Cleaner energy for a better future
Encouraging innovation in marine technology is at the heart of the cruise industry’s efforts to reduce its environmental footprint. It has made significant investments in developing sustainable technologies and practices, including, for example, providing onshore electricity for ships. If a moored vessel can be connected directly to a power source, the engines can be turned off, reducing emissions by up to 98 percent.
Currently, only 2% of the world’s ports have shore supplies, but 46% of cruise ships are ready to call. The other 30 percent can be updated.
Another key area of development is sustainable marine fuels. Working with manufacturers and others, cruise lines are exploring different alternatives to conventional fuels, seeking to reduce their dependence on fossil fuels and transition to cleaner energy.
The IMO is calling for a five to ten percent increase in the adoption of alternative fuels across the marine industry by 2030, but sustainable fuels are not yet widely available. The availability of more new fuels in ports around the world requires urgent action by governments to invest in the necessary infrastructure.
AdvertisingOther challenges include the storage characteristics of different fuel types (some require more fuel space than others, affecting their suitability for marine use) and a number of safety issues.
Various new and alternative energy sources are being explored, such as biofuels made from plant materials and animal waste; Synthetic “electrofuels” (made from captured carbon dioxide), such as e-methane and e-methanol; Electric and hybrid batteries; biological and synthetic liquefied natural gas (LNG); methanol and hydrogen fuel cells; Wind and solar energy.
Successful trials in this area to date include a zero-GHG voyage completed by the LNG-powered MSC Euribia ship in June 2023. This was made possible with bio-based LNG using a mass balance approach. MSC is using the data from this testing to optimize the number of more ships in its fleet, reduce its emissions and, as a result, make progress towards decarbonisation goals.
Another area with huge potential is the use of methanol. If adopted as the sole energy source, green methanol (such as bio-methanol or e-methanol) is capable of turning any journey into an almost carbon-neutral one.
As an alternative fuel, methanol has already been thoroughly tested and studied, so safety and fueling considerations have already been documented. This would facilitate its widespread availability and construction of methanol-ready vessels has already begun. TUI Cruises, Celebrity Cruises, Disney Cruise Line and Norwegian Cruise Line are preparing seven ships for methanol-powered cruises.
They will be commissioned in 2028, at which time there will also be 41 ships designed for fossil-fueled LNG, all of which can be easily retrofitted for greener LNG when they become more widely available.
Other pilot programs include 26 vessels testing biofuels and synthetic carbon fuels, while hydrogen and methane fuel cells, photovoltaics and wind energy are also being tested and tested.
The role of ship design in energy efficiency
Along with the race to find cleaner fuel, there are efforts to make engines and ships more energy efficient. Future-proof ships currently under construction are an important part of meeting emissions targets. The average lifespan of cruise ships is about 30 years, but marine technology is changing all the time. Discovering potential innovations has become fundamental to ship design, along with incorporating the latest developments in technology.
These advances include smart lighting and efficient HVAC systems, along with better waste management. Cruise lines are investing heavily in advanced wastewater treatment systems, which are much more efficient than using land-based treatment plants. It can also capture wasted energy, produced by even the most efficient engines. Cruise lines have begun installing heat exchangers that convert steam generated by engines into fresh water for showers, swimming pools, kitchens, and warming cabins.
Integrated air lubrication systems are increasingly being introduced into cruise ship design. This directs air into the underbody, creating microscopic air bubbles that reduce drag, conserve energy and contribute to fuel efficiency.
AdvertisingThe design of the hull itself is also a key factor in reducing bow wave resistance, along with antifouling coating. These have improved dramatically in recent years, with the availability of environmentally friendly silicone-based paints, varnishes and coatings.
Alongside physical technology, software has also played a major role in decarbonisation within the cruise industry. Software used to improve fuel and energy efficiency has had a significant impact on carbon emissions, as have tracking systems that help, for example, guide ships to harness energy from currents. Digital technologies collect and analyze data on speed, route, engine performance and emissions data and transmit it to the operating crew.
Working together towards net zero
The cruise industry cannot achieve its decarbonization goals alone, and CLIA member lines collaborate with governments, the European Union, fuel suppliers and technology companies, who play a key role in developing solutions that improve the energy efficiency of cruises.
Governments also play a critical role in creating the regulatory framework to support the production, distribution and use of renewable fuels. CLIA’s work with governments includes promoting policies that promote green technology, emissions reductions and energy-efficient ship designs.
This includes faster access to financing for shipbuilding and marine equipment manufacturing and the development and supply of affordable sustainable fuels at scale, all of which will be essential to achieving the global goals.
• To learn more about the cruise industry’s commitments to reduce its environmental footprint, see Cruising.org.
(tags for translation)sustainable development
