Cruise Lines International Association (CLIA) has released its latest “Environmental Technologies and Practices (ETP) Report,” showing steady progress across the global cruise industry in areas ranging from alternative fuels and energy efficiency to advanced wastewater treatment and waste reduction systems.
The report profiles CLIA-member oceangoing cruise lines, which represent more than 90 percent of the cruise sector, and tracks data from 2018 through 2024. Key findings include an increase in multi-fuel capable ships, more widespread use of onshore power supply, and expanded wastewater treatment and waste management technologies.
“Cruise lines are early adopters and innovators of maritime technology — examples include advanced wastewater systems, onshore power supply, air lubrication systems, and the newest generation of dual-fuel engines—from which other sectors of maritime also benefit,” said Bud Darr, president and CEO of CLIA. “Cruise lines are investing tens of billions of dollars to build the fleet of the future, including more than 80 new ships on order worldwide that feature these and other innovations. These orders represent tangible steps that are significantly enhancing the operational capability and efficiency of the collective global cruise ship fleet of our members.”
Fleet Snapshot
As of August 2025, CLIA represents 45 cruise lines operating 310 ships with 637,847 lower berths. The majority of ships (73 percent) fall into the small- to mid-size category with fewer than 3,000 berths. Looking ahead, CLIA expects this balance to remain consistent through at least 2036, according to its current orderbook.
Fuel Flexibility and Alternative Energy
One of the most significant shifts has been the growth of multi-fuel engine technology. In 2018, only one ship operated with a multi-fuel engine. Today, there are 19 dual-fuel ships, with 23 expected to be in service by the end of 2025, including the first with tri-fuel capability. By 2036, 32 dual-fuel ships are forecasted to launch, including seven able to run on methanol and 25 capable of using LNG.
Cruise lines are also piloting biofuels and increasing uptake of alternatives to heavy fuel oil. A ship delivered in 2024 is slated to be methanol-ready by 2026, with another methanol-capable vessel set for delivery this year.
Onshore Power Supply (OPS)
OPS, which allows ships to shut down engines while in port, has expanded significantly. In 2018, just 55 ships had the ability to connect. Today, 166 CLIA-member ships (58 percent of the fleet) have OPS capability, representing 65 percent of global capacity. By 2036, 273 ships are expected to have this feature.
Currently, only 41 ports worldwide (less than 3 percent) have cruise berths with OPS. Europe has led the expansion in the past 18 months, with six additional ports offering OPS, while North America and the U.K. each added one. Another 45 ports worldwide have secured funding or announced plans to install OPS.
Wastewater, Water Production, and Waste Management
Advanced Wastewater Treatment Systems (AWTS): 234 ships (82 percent of the fleet) are now equipped with AWTS, up 72 percent since 2018. More than one-third meet the stringent standards of the Baltic Sea Special Area.
- Freshwater Production: 279 ships (over 98 percent of the fleet) produce the majority of their freshwater onboard through systems such as steam evaporation and reverse osmosis.
- Waste Management: Technologies such as microbial digesters for food waste (in use on 128 ships) and waste-to-energy gasification (on eight ships) are becoming more prevalent.
Looking Ahead
CLIA notes that while only a small percentage of ports worldwide currently have OPS, regulatory frameworks such as the EU’s Fit for 55 decarbonization package will accelerate investment in port infrastructure. By 2030, major ports in Europe will be required to offer shoreside power.
Now in its eighth year, the “ETP Report” underscores the cruise industry’s continued investment in building a cleaner, more efficient global fleet.
For more information and to view CLIA’s full “ETP Report,” visit Cruising.org.
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