ES200 Energy Storage

Store and retrieve energy to improve efficiency and comfort.

Improved generator efficiency and emissions

Under loaded generators operating outside their efficiency zones often causes increased fuel consumption, leading to higher emissions and unexpected maintenance issues. The Magnus ES200 Energy Storage System can maintain the generator operation inside the efficiency regions saving time, money and the environment.


Virtual generator mode

The Virtual Generator operating mode is unique to the ES200 power electronic platform and mimics the behaviour of regular rotary generators. Interfacing the ships generator(s) with a balanced 3-phase voltage delivers a true dynamic system with bi-directional connectivity. The benefit of this is a natural connection between the generator(s) and the Energy Storage System. In addition physical inertia is modelled by the system, providing a stable response to the grid frequency. The ES200 Virtual Generator can control its own voltage and frequency, enabling it to create an island grid should a problem occur with the generators or shore supply. In such condition the ES200 will support the load without disturbance. Changing modes between power flow and voltage & frequency control is possible without stopping the ES200 and is achieved with seamless transfer of power.

Seamless Storage of energy

As the ships load fluctuates excess generator power can be stored by the energy storage system. Stored energy can then be used when power demand exceeds that of the generator(s). Using the energy storage system during peak periods prevents additional generators from starting. Operating the ship in this configuration offers significant fuel savings which would have otherwise been lost. Additionally maintaining the generator at its nominal load keeps generator run hours, maintenance and exhaust fumes to a minimum.


SY Ethereal is a high performance Royal Huisman 58M Ketch and is the only Sailing vessel in the world with a hybrid diesel electric propulsion/power generation system utilizing a 700 VDC Bus system.

Magnus Marine supplied the Grid convertors and Shore Power Convertors for this highly technical project, adding their technical expertise to the development of the hybrid system. I was not personally involved with build process at the yard, however I have been onboard Ethereal Since 2010 as Chief engineer and have worked with Mathew Scales personally.

Due to the highly technical nature of this equipment, after sales servicing and spare part supply is critical to the continued performance of this equipment. Mathew Scales has always been available to give technical advice and has visited the yacht several times to service the units.

We are now at the 5‐year maintenance period of these units and are due a visit from Magnus Marine, apart from a health check and the replacement of serviceable items these units have worked faultlessly for years. I would highly recommend Magnus Marine products as part of any power distribution system.

Christian Lawson-Mckittrick, Chief Engineer, S/Y ETHEREAL


Benefits, Specifications & Package

Key features

  • Peak Shaving - Deliver power to the grid when peak demand is high. Unloading, preventing an additional generator coming online thereby lowering fuel and maintenance costs
  • Spinning Reverse - Meet shortfalls; supply backup power during a loss of generation silent ship operation
  • Load levelling - Store energy when demand is low and deliver energy when demand is high
  • Design maximises battery life expectancy

Battery specification

  • Lithium-ion Manganese Oxide
  • High strength resistant towards vibration and external shocks via employment of cylindrical case (stainless steel and wind around electrolyte)
  • 3 times charge and discharge performance
  • Battery Management Unit monitoring voltage, temperature and charging/discharging
  • Operating temperate -20 to 50°C
  • Efficiency >96% (end of life)
  • 1.7kW/h = H:151 x W:228 x D:475mm 23kg
  • 102Watt hours/litre 76Watt hours/kg
  • Life expectancy 8000 cycles

Package includes

  • Battery Management Unit to monitor each battery and includes safety shut off
  • Energy Management Unit with Graphical Display for Control and Monitoring.
  • Control profiles for easy crew accessibility
  • 110V battery string isolation for safety
  • Upstream current protection from converter and energy storage
  • Converter(s) with Graphical Display for Control and Monitoring
  • Standalone or remote operation with PMS