Electric and hybrid drives

Electric and hybrid systems

Hybrid drive is a combination of an electric motor and a combustion engine. We design and build low and medium power electric-combustion drives. When selecting an engine for a vessel, we match the power to achieve the hull's maximum speed, while the electric drive is matched to achieve the vessel's cruising speed.

With this drivetrain solution, we have a quiet and eco-friendly electric motor at our disposal, while the combustion engine serves as a backup. The electric motor can also be used to charge the batteries both while the combustion engine is running and while sailing. Charging is effective at approximately 2/3 of maximum displacement speed. In light winds, charging can be switched off, which will reduce propeller drag. The Beta Hybrid drive is available for engines equipped with PRM150 or PRM500 gearboxes.

Most hybrid systems rely on a permanent connection of the combustion engine and electric motor into a single unit. However, the electric motor can be installed anywhere along the shaft line. One of our solutions is built around the Python Drive assembly, which allows the electric motor to be separated from the combustion engine. This is advantageous because electric motors do not tolerate excessive heat emitted by combustion engines. An additional benefit is the remarkable ease and flexibility of installing the electric drive with any engine.

Hybrid or fully electric systems are available in the following power ratings: 4.7 kW, 7.2 kW and 14.4 kW. Higher power ratings are available on request.

In our solutions, electric motors can also serve as generators. The electric motor, driven by the combustion engine or by the propeller spinning while sailing, charges the drive batteries. (With a minor system modification, the domestic batteries can also be charged.)

When charging batteries via the combustion engine, a high charging output is achieved without overloading the engine, resulting in improved overall drivetrain efficiency as less energy is wasted.

If, while sailing, the propeller is allowed to spin freely, it will drive the electric motor, which will act as a generator. The efficiency of such charging is lower, but the energy is free. The amount of energy is directly proportional to speed and depends on the efficiency (selection) of the propeller itself. It is generally accepted that a 'dragged' propeller operates at only 40% of its normal efficiency, due to the unfavourable reversal of pressure on the blades.

Single hybrid motor (Beta 20 – Beta 60)

Engines in the Beta 20 to Beta 60 range are equipped with a single motor/generator providing 10 kW of electric drive power, and 6 kW in generation mode (9 kW with optional boost alternators).

Dual hybrid motor (Beta 75 – Beta 150)

From Beta 75 to Beta 150, engines are equipped with a dual motor/generator providing a combined 20 kW of electric drive power, and a combined 12 kW in generation mode (16 kW with optional boost alternators).

Controller and control panels

The electric motor/generator is connected to a master control box, which is operated via a control panel.

Batteries

Sealed batteries are required for marine vessels, so AGM batteries are used. The electric drive runtime will depend on the size of the available battery bank, but a 40-foot vessel requiring 4 kW to achieve 5–6 knots, using a 48V/200Ah battery bank (4x 12V/200Ah), would be able to travel for 2 hours at 5–6 knots. Increasing the battery capacity will allow for higher speed or longer runtime.

Additional charging options

Solar panels can also be fitted as an additional option. Adding solar panels can contribute significantly to meeting the vessel's energy needs.