Intelligence · Fleet

Ship Performance Curves

How fuel scales with speed. Main-engine consumption follows the propeller law — burn ∝ speed³ — so slowing down saves fuel fast. We anchor each segment to its vetted design speed and overlay the speed the fleet is ACTUALLY steaming from live AIS: the slow-steaming reality.

4segments

Analytics

Decarbonization banked in slow-steaming

The merchant fleet is steaming on average ~23% below design speed right now — roughly 53% less main-engine CO₂ than design-speed operation, under the propeller law. A real, already-realised emissions cut the market took for fuel economics, visible directly in live AIS speeds.

Dry Bulk

44% slow-steam saving

Design

13.5 kn

Steaming now

11.1 kn(9–13)

Main-engine fuel

~18 t/d/ 32 design

n = 4,217 live fixes.

Tankers

58% slow-steam saving

Design

14.5 kn

Steaming now

10.9 kn(8–13)

Main-engine fuel

~21 t/d/ 50 design

n = 592 live fixes.

Container

75% slow-steam saving

Design

21.0 kn

Steaming now

13.3 kn(9–17)

Main-engine fuel

~38 t/d/ 150 design

n = 1,566 live fixes.

Gas (LNG/LPG)

43% slow-steam saving

Design

16.0 kn

Steaming now

13.3 kn(9–17)

Main-engine fuel

~55 t/d/ 95 design

n = 81 live fixes — low confidence.

Method: main-engine fuel scales as (speed / design speed)³ (the propeller / Admiralty law), anchored to each segment’s vetted design speed and a representative consumption — so the slow-steaming % is robust while the absolute t/day is a representative figure. The “steaming now” speed is the live-AIS median of underway vessels in the segment (we have no noon-report fuel, so we observe the speed and anchor the burn to physics, never the reverse). This curve is the substrate the route economics, carbon-cost and TCE estimates draw on.