Some of the new ships include pilot projects and trials with new fuels that are currently underway. The study notes that an increasing number of the ships already in operation or due to debut in the next five years will use alternative fuels or will be able to incorporate zero-carbon fuels as they become available.

The report also highlights shipping companies' commitment to grid connection in ports, which makes it easier to switch off engines when ships are moored, significantly reducing emissions.

"The ships of the future are being built today; they will use new and more sustainable technologies," says CLIA President & CEO Kelly Craighead.

Connecting to the grid

• 120 ships in CLIA's fleet (46% of the total) are equipped with systems that enable electrical connection to shore. They will be joined by 86% of the ships making their debut in the next five years.

• Currently, 32 ports (compared to 29 in 2022) have electrified quays - less than 2% of ports worldwide.

• By 2028, more than 210 ships (72% of the fleet) are expected to be grid-connected.

Advanced wastewater treatment systems

• 77% of CLIA's fleet (202 ships) are equipped with wastewater treatment systems.

• 100% of newly built ships will be equipped with these systems, which will mean that 242 ships will be equipped with this technology (80% of the fleet).

• Since 2019, the number of ships equipped with wastewater treatment systems that meet the (stricter) Baltic Special Area standards has increased by 167%. Today, about one third of CLIA's fleet has this capability.

Renewable fuels and alternative energy sources

• Within the CLIA fleet, four ships already use biofuels as an energy source and four more will be equipped to use them.

• Trials are underway with biofuels on 24 ships and synthetic fuels on two.

• Seven ships under construction are expected to use zero-carbon fuels: five of them will use green methanol and two will use green hydrogen.

• 15 % of new ships entering service in the next five years will use batteries and/or fuel cells to enable hybrid power generation systems.

Liquefied Natural Gas (LNG)

• 48% of new-build ships will be built with LNG engines. They belong to a new generation of ships that will be able to use sustainable marine fuels once suppliers make them available at scale.

• LNG is currently the best performing fossil fuel available at scale in terms of reducing atmospheric emissions, according to an analysis by SeaLNG and others.

The study "Environmental Practices and Technologies 2023" points out that, in order to have greater fuel flexibility, cruise companies are investing in propulsion systems that can be compatible with different solutions. Along these lines, 32 collaborative projects are being implemented with fuel companies and engine manufacturers.

But it is also necessary that "governments support research in this area and establish a clear and stable regulatory framework, so that fuel suppliers and other actors can make the necessary developments," says CLIA president Pierfrancesco Vago.

Regarding shore-side grid connection, CLIA recalls that in 2022 it committed that by 2035, ships docking in ports where this grid is available must use the same or alternative low-carbon technologies (depending on availability) to reduce emissions in port.