There is an electric motor that promises to challenge the idea of finite autonomy: let's talk about Oceanvolt ServoProp, an engine that uses the power of wind and water to recharge the batteries of electric sailboats.
Many imagine sailboats as vehicles propelled exclusively by the wind. This may be true for smaller ones: larger boats need an engine to maneuver in harbors or when the wind is low. In this case, the engine is a saildrive. How exactly does it work?
Saildrive: innovation in the propulsion of sailboats
Saildrives are innovative propulsion systems, often fitted to modern sailboats. These engines, integrated directly into the hull, offer a compact and efficient alternative to traditional shaft-driven engines.
Thanks to their aerodynamic design and absence of vibrations, sail drives improve navigation performance and reduce environmental impact.
Above all, Saildrives have a unique advantage: hydraulic regeneration. When the boats are pushed by the wind, the water flowing over the propeller spins the engine backwards, turning it into a generator that recharges the batteries.

Oceanvolt, both propulsion and regeneration
The ServoProp developed by Oceanvolt has a special feature. This engine combines innovative variable pitch blades with the ability to rotate 360 degrees. Result? An optimal environment for both propulsion and regeneration.
In propulsion mode, the motor delivers 25 kW of continuous power, with a peak power of 30 kW for 15 minutes. Instantaneous torque and thrust of 5.000 newtons (about 1.100 lb.) are further benefits of the electric system. Oceanvolt claims that the 25 kW power rating is comparable to the performance of a 75 kW (100 hp) combustion engine.
In summary
The 190 kg saildrive is suitable as a propulsion engine for boats up to approximately 20 meters (70 feet) in length and weighing up to 25 metric tons. It can also be used as a simple hydraulic regenerator on larger vessels.
Deliveries of the new ServoProp are scheduled for the end of the year.
Another step forward in the nautical world, which allows electric sailboats to exploit natural resources such as wind and water to regenerate energy.