If you care about cleaner seas and quieter ports, the latest CLIA findings are worth a look. The industry’s Environmental Technologies and Practices Report points to steady progress, from fuel-flexible engines and plug-in power at the pier to smarter water and waste systems that reduce draw on destinations while keeping holidays simple for guests.
CLIA’s 2025 review covers 2018-2024 data for member lines representing about 90 percent of oceangoing capacity, noting 19 dual-fuel ships in service and more on order, expanding OPS capability across the fleet, increased SCR installations for NOx control, broad AWTS coverage, near-universal onboard freshwater production, and first-wave waste technologies that cut landfill and energy demand.
This report is more than policy notes, it shows how ships run day to day and how ports feel when you step ashore. The headline is practical, fuel flexibility is rising, shore power is spreading, and treatment systems below deck are becoming standard, which together nudge cruises toward lower local impacts without changing the way you holiday.
CLIA members now field 19 dual-fuel ships, up from one in 2018, with more fuel-flexible engines arriving by the end of 2025 and through the 2036 orderbook. These platforms can operate on today’s compliant fuels, then adopt near-zero or zero-emission fuels such as LNG or methanol as supply scales, often without major engine changes. For guests, the upside is incremental yet real, cleaner stacks, reliable itineraries during the transition, and a pathway to lower lifecycle emissions on routes you already enjoy.
Onshore power supply (OPS) lets ships switch off engines in port and draw electricity from the grid, reducing local emissions and vibration while you explore. Fleet capability has climbed sharply since 2018, with 166 ships now able to plug in, and hundreds expected by the mid 2030s. Port infrastructure is catching up in phases, so you will notice the benefit first in regions that are investing early, while ships use compliant fuels and controls where plugs are not yet available.
Adoption of selective catalytic reduction (SCR) has moved from niche to mainstream, growing from seven ships in 2018 to 81 today. SCR treats exhaust to reduce nitrogen oxides, improving air quality near busy waterfronts, and it sits alongside efficiency tools like air-lubrication and advanced hull coatings. You see the result indirectly, fewer fumes on still mornings and a calmer soundscape in port, small gains that add up across a large fleet.
Much of the progress happens below deck, away from the holiday moments you remember. Even so, the effects are felt ashore, less pressure on local water, cleaner discharges under strict rules, and smarter handling of everyday waste streams.
Modern plants mean most CLIA ships make their own freshwater through reverse osmosis and evaporation, covering the vast majority of daily needs. That reduces reliance on port supplies during dry spells and lets itineraries reach smaller islands without drawing on limited resources. For you, it simply means consistent showers, dependable taps, and stable service regardless of where the ship is sailing.
Advanced wastewater treatment systems (AWTS) now span most of the CLIA fleet, with a rising share capable of meeting tighter standards set for special areas like the Baltic. Lines also commit not to discharge untreated sewage during normal operations, a straightforward safeguard that resonates with guests and destinations alike. The direction is set, by the mid 2030s, even more ships will carry AWTS as new builds arrive and existing vessels are retrofitted during scheduled dockings.
Waste tech is evolving on two fronts, waste-to-energy gasification on a handful of ships and microbial digesters for food waste on many more. Gasification converts certain materials to syngas for onboard use, trimming landfill and offsetting a slice of energy demand. Digesters reduce the volume and odour of organics, improving hygiene and safety behind the scenes, while better guest-facing sorting keeps the system flowing smoothly in hot climates.
Ships can only use what ports provide, which is why shore-side investment and policy shifts matter. The map is uneven today, yet it is moving in a helpful direction for travellers who value cleaner air and quieter piers.
Europe is accelerating OPS under the Fit for 55 rules that require many major ports to install shore power by 2030, and the UK and North America have added new plug-in cruise berths in the last year. As clusters of OPS-ready terminals emerge, lines can plan voyages that string together multiple plug-in calls, making the benefits more noticeable on a single holiday. Elsewhere, individual ports are securing funding and publishing timelines, a sign that availability will broaden year by year.
OPS is only part of the picture. Ports are also improving berth allocation, arrival pacing, and terminal links to public transport, which reduces idling, tug time, and short taxi hops. When shore-side recycling partnerships expand, sorted materials from ships find better end uses, a quiet gain you will not need to think about while you are out exploring.
A few filters help you align values and comfort. Look for ships that list OPS, AWTS, and SCR among their features, then scan itineraries for ports that advertise plug-in berths. If fuel notes mention dual-fuel or multi-fuel engines, that signals readiness for cleaner options as supply grows. Treat these details like dining or entertainment choices, features that shape your experience even if you never see the machinery.
Before you start comparing ships, it helps to map the sailings that match your month, ports, and flight plans. Our Cruise Finder makes it easy to filter by region and date, then save the departures that suit your calendar:
If you already have a shortlist, use Cruise Finder to compare ship features and port lists, then favour OPS-ready vessels and routes with cleaner-fuel notes where available. It is a simple way to put the insights from the Environmental Technologies and Practices Report to work on your next holiday.
The Environmental Technologies and Practices Report shows steady, measurable change, from fuel-flexible engines and shore-power connectivity to mainstream AWTS and smarter waste handling. You do not need to compromise to support that progress, you just need to choose ships and itineraries that use the tech where you sail. If you would like tailored options that fit your dates, budget, and sustainability goals, message our team cruise specialist, and we will curate a plan that feels right.