Cruise Lines International Association has just published its 2025 snapshot of environmental technology adoption across 98 % of global oceangoing capacity. The numbers show a fleet in active transition: 30 ships already carry multi-fuel engines that can switch between conventional fuels and near-zero-emission options, with another 26 on order for 2030 delivery and 39 more penciled in by 2039. The shift is visible in the fuel mix: heavy fuel oil fell from 74.2 % of cruise-ship consumption in 2019 to 60.6 % in 2024, while non-HFO fuels—diesel, LNG, low-sulfur blends—rose from 25.8 % to 39.4 %. CLIA’s own 2025 returns put non-HFO at 40.3 %.
Shore power is expanding faster than the ports can keep up. CLIA-member ships capable of plugging into local grids have jumped from 55 in 2018 to 193 today, covering 65 % of reporting ships and 72.5 % of capacity. Another 47 retrofits and 39 newbuilds are slated, which would lift the total to 279 ships by 2039. The technology can cut dockside emissions, but availability hinges on compatible infrastructure; only 40 cruise ports worldwide have at least one berth wired for shore power.
On the water side, selective catalytic reduction systems have gone from seven installations in 2018 to 96 in 2026, slashing nitrogen-oxide emissions at sea. Almost every reporting ship—293 out of 297—can now produce freshwater onboard, and 218 can meet their entire need without topping up in port. Advanced wastewater treatment systems sit on 249 ships, up from 136 in 2018; CLIA members state all their vessels are equipped and committed to zero untreated sewage discharge during normal operations. Food-waste digesters have spread to 137 ships since CLIA began tracking them in 2022, and seven vessels now run waste-to-energy gasification units.
Bud Darr, CLIA president and CEO, frames the next phase as a shared challenge. “Realizing the full potential of those investments will require fuel producers, governments, ports, energy providers, and other stakeholders to help create the conditions for safe, competitively priced renewable and lower-emissions fuels to be available at scale.” The data make clear that cruise operators have crossed the technical threshold; the constraint now is infrastructure and supply chain readiness.