CLIA Releases Annual Report on Environmental Technologies and Practices

Cruise Lines International Association (CLIA), the leading voice of the global cruise industry, has just released its annual Environmental Technologies and Practices (ETP) Report. The report profiles member companies' cruise fleets and highlights the environmental technologies currently in use, representing over 90% of the cruise industry.

This year's report highlights the continued, measurable progress CLIA member companies are making on their ambitious environmental agenda—from testing and piloting biofuels and investing in flexible-fuel engines to increasing the use of low-emission fuels and maximizing energy efficiency measures.

"Cruise lines are pioneers and innovators in maritime technology—examples include advanced wastewater treatment systems, shore power, air lubrication systems, and the latest generation of dual-fuel engines—from which other maritime sectors also benefit," said Bud Darr, president and CEO of CLIA. "Lines are investing tens of billions of dollars to build the fleet of the future, including more than 80 new ships ordered worldwide with these and other innovations. These orders represent concrete steps that significantly expand the operational capacity and efficiency of our members' collective global fleet," Darr added.

Highlights from the 2025 Environmental Technologies and Practices Report

As of August 2025, 45 cruise lines were CLIA members, representing 90% of global ocean capacity. Together, they operate 310 ships and 637,847 beds, compared to 303 ships and 645,034 beds the previous year.

The majority of the fleet (73%) is composed of small and medium-sized vessels (<3,000 berths). Until 2036, the ratio between small, medium, and large vessels is expected to remain relatively balanced.

Towards net-zero emissions and greater operational efficiency.
Multifuel vessels: In 2018, there was only one vessel with dual-fuel engines. Today, there are 19, and 23 are expected by the end of 2025 (including the first with trifuel capability). By 2036, 32 dual-fuel vessels are expected to be delivered.

Adoption of alternative fuels: ships are already prepared to operate with methanol and LNG, in addition to tests with biofuels.

Shore-based power (SSP/SSE): In 2018, 55 ships had the capability to connect to power in ports. Today, there are 166 (58% of the fleet), with a forecast increase to 273 by 2036. Currently, only 41 ports worldwide offer this infrastructure, but the trend is toward expansion, especially in Europe.

NOx reduction with SCR: in 2018 there were 7 ships with Selective Catalytic Reduction systems; in 2025 there will be 81.

Water and effluents
Fresh water production on board: 279 ships (more than 98% of the fleet) have desalination systems and other processes that reduce dependence on ports.

Advanced Wastewater Treatment (AWTS): 234 ships (82% of the fleet) already have these systems, capable of exceeding MARPOL Annex IV requirements. More than a third meet the strictest Baltic Sea standards. The number of ships expected to be 273 by 2036 is expected.

Waste management
Advanced management technologies: some ships are now able to recycle or reuse almost all of the waste generated on board.

Waste gasification systems: present on 8 ships, they transform waste into energy.

Microbial digesters for food waste: On 128 ships (45% of the fleet), they significantly reduce food waste — a practice that was almost non-existent five years ago.

Source: CLIA Global.