Hybrid

Hybrid Propulsion

There are two types of Diesel Electric Hybrid Systems, the Serial Hybrid and the Parallel Hybrid.

 

The Serial Hybrid

The Serial Hybrid consists of an electric motor driving the propeller from batteries that are recharged by a DC generator.  The advantages of this system are:   the components are optimized,  the electric motor is perfectly suited to the propeller with the correct gear ratio,  the generator is perfectly suited to charging the battery bank, and the simplicity of the system allows for easy maintenance.   The automotive equivalent of this system is the Chevy Volt.

Our preference is the Serial Hybrid for sailboats, because both electric motors and diesel generators are very reliable and the Serial Hybrid Design is more in line with how a sailboat is used.    Additionall, the small size of the propulsion motor allows for flexibility in the design of the interior layout of the boat, and the diesel generator can be installed outside of the living spaces of the boat in an aft lazarette.   The diesel generator in a serial hybrid design can be either smaller than the electric motor – for boats that use solar as their primary source of power and require the diesel as a backup, or larger than the electric motor – for boats that have heavy house loads and big batteries and wish to minimize diesel engine run time.

In the coming months we will be introducing the first affordably priced serial hybrid to complement our existing line of Polar Power based Serial Hybrid Combinations.   Stay tuned or email us for more information on this exciting new development.

 

The Parallel Hybrid

The Parallel Hybrid consists of a diesel motor and an electric motor, each capable of driving the propeller individually or at the same time.   The advantages of this system is the redundancy of having two different motors capable of driving the same propeller.   The automotive equivalent of this system is the Toyota Prius.  Both Beta Marine and Steyr Motors make Parallel Hybrid Marine Engines.     Typically the diesel engine is more powerful than the electric motor.

The Parallel Hybrid is perfect for powerboats who want a high powered diesel motor yet wish to have the flexibility of electric motor sailing and / or electric harbor maneuvering.    The Parallel Hybrid is better for motor yachts that require high power from the diesel engine for normal running conditions.