Electric & Hybrid Electric Ship Propulsion Systems

Electric & Hybrid Electric Ship Propulsion Systems

Efficient, power-dense, flexible solutions for advanced ship propulsion

Leonardo DRS motor and drive systems provide advantages in flexibility, modularity, and commonality – supporting requirements for growing power efficiency demands and lower emissions on future ships.

We provide solutions for integrated electric drive (IED) and hybrid electric drive (HED) ship propulsion systems. HED arrangements can be gear-mounted or shaft-mounted depending on the ship’s architecture.

Efficient Power

Our marine electric propulsion systems are constructed with permanent magnet (PM) technology that is extremely efficient and delivers remarkable power density, impressive durability, and easier maintainability when compared to induction or wound rotor synchronous machines. Any propulsion system that leverages electric drive will lower emissions. However, PM technology is uniquely suited to provide the maximum range of electric drive benefits for ship propulsion and power for ship systems.

Reducing risks

During replenishment at sea, the time spent alongside the re-fueling ship puts both ships at greater risk. HED propulsion systems reduce refueling requirements providing more time on station and less time at risk.

Benefits of Our E-Drive Technology


  • Prime movers operate at most efficient, constant speed,
  • Controllable pitch propellers may also be eliminated
  • Power generation equipment can be switched on and  off as needed


  • Flexibility in locating the prime movers across the platform (IED)
  • Additional redundancy on the drive shaft (HED)
  • Ability to send the power where needed (IED)
  • No need to align prime movers with the shafting (IED)


  • For all-electric configurations noise and vibration are improved by elimination of the main reduction gear
  • Shaft-mounted hybrid electric drive makes it possible to decouple the reduction gear 
  • Both configurations benefit from prime movers running at a constant speed


  • Reduction of the total number of prime movers to maintain
  • Possible elimination of controllable pitch propellers and their support systems
  • Less wear and tear on prime movers as they are operated under less stressful conditions

Machine Configuration Examples

1.7 MW Shaft-Mounted Hybrid Electric Drive (HED) Motor1.7 MW Shaft-Mounted Hybrid Electric Drive (HED) Motor

For hybrid electric drive architectures requiring a shaft-mounted motor, Leonardo DRS offers power-dense, low speed PM motors with a large air gap that allow for a bearing-less configuration, simplifying the propulsion shaft.

1.5 MW Gear-Mounted Hybrid Electric Drive (HED) Motor1.5 MW Gear-Mounted Hybrid Electric Drive (HED) Motor

The lightweight, compact size of Leonardo DRS PM motors is ideal for hybrid electric drive architectures requiring a gear-mounted solution.

36.5 MW Integrated Electric Drive (IED) Motor36.5 MW Integrated Electric Drive (IED) Motor

For full electric drive ship propulsion systems, Leonardo DRS PM motors provide a number of advantages including significant torque density. Our 36.5 MW example is a 50,000 HP machine that is approximately 17 feet square at just over 125 tons and produces more than two million ft. lbs. of torque!

Power-dense 625HP Hybrid Electric Drive (HED) MotorPower-dense 625HP Hybrid Electric Drive (HED) Motor

Selected to provide hybrid electric drive propulsion for the U.S. Coast Guard Offshore Patrol Cutter program, the power-dense, water-cooled PA44 is only 395 lbs. and rated up to 625 HP providing 1,100 ft-lbs. @ 3000 RPM.

Hybrid Electric Drive Gear or Shaft-Mounted Arrangements

Shaft-Mounted Hybrid Electric Drive Motor Configuration

Shaft-Mounted Hybrid Electric Drive (HED) Motor Configuration

Lower noise signature than gear-mounted motor.

Gear-Mounted Hybrid Electric Drive (HED) Motor Configuration Gear-Mounted Hybrid Electric Drive (HED) Motor Configuration

Compact arrangement with high shock capability.



Hybrid Electric Demonstration

Our HED solutions deliver advantages in flexibility, modularity and commonality; supporting requirements for fuel savings and growing power efficiency demands on future ships.