CLIA released its Annual Report on Environmental Technologies and Practices

The Cruise Lines International Association (CLIA), the global cruise industry's spokesperson, has released its annual Environmental Technologies and Practices (ETP) report. The report profiles CLIA's oceangoing cruise fleet and highlights the environmental technologies used by these lines, which represent more than 90% of the cruise industry.

This year's report shows continued progress by CLIA member cruise lines on their environmental agenda, from biofuel testing to investing in flexible engines, increasing the use of lower-emission fuels, and maximizing energy efficiency measures.

CLIA President and CEO Bud Darr noted that cruise lines are pioneers in the adoption and innovation of maritime technology, including advanced wastewater systems, shore power, air lubrication, and dual-fuel engines. He also highlighted that more than 80 new ships have been commissioned that incorporate these innovations, improving the operational capacity and efficiency of the global fleet.

Fleet Profile of CLIA Member Cruise Lines
By August 2025, 45 CLIA member cruise lines accounted for 90% of global ocean capacity, with 310 ships and 637,847 lower berths. The majority of ocean-going ships (73%) are small to medium-sized, and the size distribution is expected to remain balanced until at least 2036.

Small ships (<1,000 lower berths): 34.2% in 2025, 34.1% projected for 2036.

Medium-sized ships (1,000 to 3,000 lower berths): 38.4% in 2025, 35.5% in 2036.

Large ships (>3,000 lower berths): 27.4% in 2025, 30.4% in 2036.

Pursuit of Net-Zero Emissions and Operational Efficiency
The fleet is adopting multi-fuel engines that enable the switch from conventional fuels to zero or near-zero emissions. Currently, 19 dual-fuel vessels operate in port and at sea, and by the end of 2025, 23 vessels with flexi-fuel engines are expected to be in service, including the first tri-fuel cruise ship. It is projected that by 2036, there will be 32 dual-fuel vessels, including some that will use methanol and LNG.

The capacity to connect to shore-based power (OPS) has also grown significantly: from 55 vessels in 2018 to 166 currently, representing 58% of the fleet and 65% of capacity. By 2036, 273 vessels are expected to be able to connect to OPS, while currently only 41 ports worldwide have this infrastructure. Europe is leading the expansion, and the "Fit for 55" decarbonization regulations will further drive investment in shore-based power.

Emissions Reduction and Water Treatment
SCR technology, which reduces particulate and nitrogen oxide emissions, has increased tenfold across the fleet since 2018, reaching 81 vessels with SCR systems.

Regarding wastewater treatment, 234 vessels (82.4% of the fleet) are equipped with Advanced Wastewater Treatment Systems (AWS), capable of exceeding the requirements of MARPOL Annex IV, and more than a third comply with the stricter standards of the Baltic Sea Special Area. By 2036, 273 vessels are expected to be equipped with these systems.

Water Production and Waste Management Onboard
Most CLIA-member cruise ships produce most of their water needs onboard, using technologies such as steam evaporation and reverse osmosis, with 279 ships representing more than 98% of the fleet.

In waste management, technologies such as waste-to-energy gasification systems and microbial digesters for food waste are being implemented on eight and 128 cruise ships, respectively, significantly improving the sustainability of operations.

Source: CLIA.