10 articles
Podded electric drives put the propulsion motor inside a steerable underwater gondola and now power more than 100 cruise ships and 80 ice-going vessels, led by ABB's Azipod. In September 2026 Kongsberg Maritime extended its Elegance pods to 22 MW, the first credible challenge to ABB in the mega-cruise class in over a decade.
Mechanical azimuth thrusters transmit engine or motor power through right-angle gears to a steerable propeller, giving tugs, offshore and DP vessels 360-degree thrust vectoring. The market is small, roughly USD 0.5 to 0.6 billion a year by aggregator estimates, so growth comes from permanent-magnet, hybrid and underwater-mountable designs rather than volume.
A fixed-pitch propeller is cheaper and 2 to 5 percent more efficient at its design point, while a controllable-pitch propeller keeps the engine at constant speed and delivers better astern thrust. In 2025-2026 the CPP has become the spine of hybrid cargo ships and the object of consolidation, with Kongsberg Maritime acquiring Berg Propulsion.
A contra-rotating propeller pairs a coaxial aft propeller turning opposite to the forward one, recovering rotational energy for vendor and model-test gains of roughly 7.6 to more than 10 percent. Hurtigruten's Sea Zero zero-emission ship and SINTEF's 2025 testing of Brunvoll's CRP have revived a concept long held back by shaft-in-shaft complexity.
A waterjet draws water through a hull inlet and ejects it through a steerable nozzle, beating propellers only above roughly 25 knots but winning on draught, stopping power and noise. In 2026 Kongsberg launched the 33 MW Kamewa S-4L and booked its largest ever waterjet order, while HamiltonJet, MJP and Thrustmaster electrify and expand the small-jet market.
Cycloidal propulsion uses a rotating disc of vertical blades to deliver thrust in any direction almost instantly, which is why Voith Schneider Propellers dominate escort tugs and double-ended ferries. Voith marked 100 years of the design in July 2026, while ABB's Dynafin concept claims up to 22% better efficiency but had no commercial order by late 2025.
A Kort nozzle accelerates flow through the propeller and can lift bollard pull by up to 30%, which makes ducted propellers standard on tugs, trawlers and icebreakers. The duct's drag erodes the gain above roughly 10-12 knots, so current nozzle development targets transit fuel economy with vendor claims of 3.5-10%.
Propulsion energy-saving devices are hull appendages such as pre-swirl ducts, stators, boss-cap fins and transom foils that recover losses around the propeller. Independently measured gains run 3-10% per device, and EEXI and CII rules let owners credit them, yet Lloyd's Register found fewer than 2% of the world fleet carries one.
Rim-driven thrusters carry the propeller blades on a rotating ring driven by a permanent-magnet motor in the duct, so there is no gearbox, shaft or blade tip. Their decisive selling point is low underwater noise, which won Kongsberg a DNV Silent-E notation in 2024, while suppliers now scale units toward 1.6-3.5 MW.
Dynamic positioning holds a vessel's position and heading with computer-controlled thrusters, and offshore wind has turned a near-standard DP2 package of azimuth, retractable and tunnel thrusters into a volume product. Spinergie counted 85 active SOVs in August 2025 with 48 more due, while cruise ships are pushing tunnel thrusters to 4,000 kW.