Cruise Lines International Association (CLIA) reports continued progress in environmental technologies and practices, including alternative fuels, shore power connectivity, advanced wastewater treatment and onboard freshwater production.
Cruise Lines Increase Investment in Environmental Technologies
The global cruise industry is making measurable progress in adopting environmental technologies and operational practices, according to the 2026 Environmental Technologies and Practices (ETP) Report published by Cruise Lines International Association (CLIA) on September 16, 2026.
The annual report tracks the adoption of environmental technologies across the cruise fleet, covering more than 90% of global oceangoing cruise capacity. Published annually since 2018, it provides year-over-year data on the industry’s progress toward greater operational efficiency and decarbonization.
The 2026 report highlights developments in alternative fuels, shore power readiness, fuel flexibility, energy efficiency, advanced wastewater treatment and onboard freshwater production.
Cruise Fleet Profile: 327 Ships Operated by CLIA Members
As of August 2026, the 45 oceangoing cruise lines belonging to CLIA operate a combined fleet of 327 ships and approximately 692,000 lower berths, representing more than 90% of global oceangoing cruise capacity.
The ETP report covers 297 ships in operation through 2025, representing 96% of CLIA-member ships and 98% of the members’ global capacity during the year.
According to the fleet analysis, 72% of cruise ships are small to mid-size vessels with fewer than 3,000 lower berths. This distribution is expected to remain relatively balanced through 2039, the final reporting year of the current orderbook.
Alternative Fuels and Multi-Fuel Engine Technology
One of the key developments highlighted in the CLIA report is the growing adoption of multi-fuel engine technology.
These engines provide the flexibility required to use zero- and near-zero-emission fuels as they become available at scale, with limited or no engine modifications.
The number of CLIA-member ships equipped with multi-fuel engines capable of switching between conventional and zero- or near-zero-emission fuels has increased from one ship in 2018 to 30 ships in 2026.
Based on the August 2026 orderbook:
- 31 multi-fuel-capable ships are forecast to be in service by the end of 2026.
- 56 ships are scheduled to be in service by the end of 2030.
- By 2039, the number is projected to reach 69 ships.
The figures reflect the industry’s ongoing investment in fuel flexibility and the transition toward lower-emission energy sources.
Cruise Industry Reduces Reliance on Heavy Fuel Oil
The report also highlights a decline in the use of traditional heavy fuel oil (HFO) and an increase in alternative fuel pathways.
According to data reported to the International Maritime Organization (IMO):
- HFO accounted for 74.2% of reported fuel use in 2019, falling to 60.6% in 2024.
- The combined use of non-HFO fuels increased from 25.8% to 39.4% during the same period.
- CLIA’s own ETP tracking recorded non-HFO fuel use at 40.3% in 2025.
The figures reflect the combined impact of more efficient ships, operational improvements, itinerary planning and investment in fuel flexibility.
CLIA also emphasizes the need for safe, scalable zero- and near-zero-emission marine fuels.
Cruise Ship Fuel Consumption and CO₂ Emissions Decline
Data from the EU THETIS-MRV database indicate improvements in average efficiency indicators for cruise ships operating in Europe.
Between 2018 and 2025:
- Average fuel consumption per reporting ship declined by approximately 18.5%.
- Average CO₂ emissions per ship decreased by approximately 19.4%.
The figures are based on CLIA’s analysis of verified ship-level data reported to the European Maritime Safety Agency.
The database covers ships sailing in Europe, although many of these vessels also operate in other parts of the world depending on seasonal operational decisions.
Shore Power Connectivity Expands Across the Cruise Fleet
Onshore Power Supply (OPS), also known as shoreside electricity or cold ironing, is another area of significant development.
The technology allows cruise ships to turn off their engines while in port and connect to the local electricity grid where the necessary infrastructure is available.
Depending on the local energy mix, shore power can significantly reduce emissions during berthing. Studies conducted by ports and regulatory agencies, including the U.S. Environmental Protection Agency, indicate that emission reductions can reach up to 98%.
193 Cruise Ships Equipped with Shore Power Connectivity
The number of CLIA-member cruise ships capable of connecting to OPS has more than tripled since 2018.
According to the 2026 report:
- The number of ships increased from 55 in 2018 to 193 in 2026.
- These ships represent 65% of reporting ships and 72.5% of reporting capacity.
- 47 ships are scheduled to be retrofitted with shoreside electricity systems.
- 39 newbuild ships are specified to be equipped with the technology.
By 2039, an estimated 279 ships are forecast to have OPS capability, representing 74% of ships and 82% of capacity.
Port Infrastructure Remains a Key Challenge
Despite the growing number of ships equipped for shore power, port infrastructure remains a significant factor in the technology’s wider deployment.
Currently, only 40 ports worldwide where cruise ships call—fewer than 3%—have at least one cruise berth equipped with OPS.
CLIA notes that realizing the full emissions-reduction potential of shore power will require continued investment in compatible port and energy infrastructure.
Under the European Union’s Fit for 55 decarbonization regulations, major European ports will be required to provide OPS by 2030, supporting further investment in regional port infrastructure.
SCR Technology Adoption Increases
Selective Catalytic Reduction (SCR) systems help reduce nitrogen oxide (NOx) emissions and support compliance with IMO Tier III emission standards.
The number of CLIA-member cruise ships equipped with SCR systems increased from seven in 2018 to 96 ships in 2026.
These ships represent 32.3% of reporting ships and 27.6% of reporting capacity, compared with 3.2% of capacity in 2018.
Onboard Freshwater Production Expands
Modern freshwater production systems enable cruise ships to meet a substantial share of their water requirements onboard, reducing reliance on supplies from ports and destinations where water resources may be limited.
Technologies include steam evaporation, reverse osmosis, aeration and other water-conservation systems.
According to CLIA:
- 293 ships, representing 98.7% of reporting ships and 99.9% of reporting capacity, can produce freshwater onboard.
- 218 ships, representing 73.4% of reporting ships and 83.3% of reporting capacity, can produce 100% of their freshwater needs onboard.
The latter group can theoretically operate without taking on additional water supplies during port calls.
Advanced Wastewater Treatment Systems Across the Fleet
Wastewater treatment remains another important area of environmental investment.
All CLIA-member cruise ships currently sailing have onboard wastewater treatment systems, while the majority use Advanced Wastewater Treatment Systems (AWTS), which can exceed the requirements of MARPOL Annex IV.
CLIA-member cruise lines have also committed to not releasing untreated sewage anywhere in the world during normal operations.
The report states that:
- 249 ships, representing 83.8% of reporting ships and 86.2% of reporting capacity, are equipped with approved AWTS.
- The number increased from 136 ships in 2018 to 249 in 2026.
- 124 ships with AWTS can meet the more stringent wastewater standards applicable to the Baltic Sea Special Area.
The figures reflect continued investment in advanced wastewater treatment technology across the cruise fleet.
Waste Management and Waste-to-Energy Technologies
Cruise lines are also deploying technologies designed to reduce waste at the source, increase recycling and reuse, and limit the volume of waste sent to landfill.
Some ships can now recycle or repurpose nearly all waste generated onboard.
Microbial Digesters for Food Waste
Microbial digesters are currently used on 137 cruise ships, representing 46.1% of reporting ships and 51.3% of reporting capacity.
These systems help process and reduce the volume of food waste generated onboard, supporting more efficient waste management.
The figure compares with 103 ships in 2022, when CLIA began tracking this specific indicator.
Waste-to-Energy Gasification
Waste-to-energy gasification remains an emerging technology in the cruise sector.
Currently, the systems are used on seven ships, representing 12,276 lower berths or 1.8% of reporting capacity.
The technology converts waste into usable energy to support ship operations and offset part of the vessels’ onboard energy demand.
CLIA Highlights the Need for Collaboration on Decarbonization
Commenting on the report, Bud Darr, President and CEO of CLIA, said that cruise lines continue to invest in technologies, fuels and operational capabilities that improve fleet efficiency and prepare the industry for the future.
Darr also emphasized the importance of collaboration between fuel producers, governments, ports, energy providers and other stakeholders.
According to CLIA, the availability of safe, competitively priced renewable and lower-emission fuels at scale, together with the necessary delivery infrastructure, will be essential to fully realizing the potential of the industry’s investments.
Cruise Industry Sustainability: Investment and Infrastructure at the Core
The 2026 CLIA Environmental Technologies and Practices Report highlights the cruise industry’s ongoing investment in environmental technologies, from alternative fuels and multi-fuel engines to shore power, wastewater treatment and onboard water production.
The findings also underline the importance of developing the infrastructure and fuel supply chains required to support the industry’s longer-term decarbonization objectives.
The report is based on CLIA’s annual survey of environmental technologies and practices and does not aim to provide a comprehensive inventory of every technology or practice used by its member cruise lines.
