The hydro generation or “creating energy while sailing” function is an automatic feature in all Oceanvolt motors. 

This feature is activated by pushing the button on the Oceanvolt displays for 5 seconds. The display will automatically switch to regeneration mode showing the current generated power, RPM and time until the batteries are fully charged. 

With a normal folding propeller the motor kicks the blades out and centrifugal force combined with the motor controller keep the blades open. The motor controllers tune the system actively at 10 Hz which prevents the blades from closing (too much braking would close the propellers). This is continuous monitoring, the system will adjust the propeller RPM depending on the boat speed. 

The system shuts itself down when the battery is fully charged or if boat speed is too low for efficient hydro generation.


The patented Oceanvolt ServoProp variable pitch sail drive combines a high efficiency sail drive with the most powerful hydro generator on the market. The unique feature of the ServoProp is the possibility to turn the propeller blades more than 180 degrees. The software controlled variable pitch sail drive adjusts the pitch of the propeller blades automatically so that the power generation and power output are optimal. Combined with uniquely designed blades it delivers optimal efficiency in both forward, reverse and hydro generation. And with the blades set to the neutral sailing position, the propeller creates extremely low drag similar to the drag of a feathering propeller. The benefits of ServoProp include an estimated +30% increase in forward propulsion, +100% in reverse and +300% increase in hydro generation effect.

A normal fixed propeller (that by nature does not have the blades ideally shaped for regeneration) generates less than half the power of ServoProp at a given boat speed. ServoProp is capable of generating more than 1 kW at 6-8 knots. The power generated can be used to power both the propulsion system as well as all the electronics on board without the need to have a separate generator. With this in mind we can definitely start talking about the possibility of a totally self-sufficient cruiser!

The ServoProp is suitable as a propulsion motor for monohulls up to 50 ft & multihulls up to 60 ft. It can also be used as a hydro generator in boats up to 100 ft.

Videos of hydro generation

power created by hydro generation

Hydrogeneration Estimate for Saildrive 15 & ServoProp 15 (1)

Oceanvolt systems are optimised for either 2 or 3 blade Flexofold folding propellers & Gori propellers.  Other folding propellers can also be used but they provide 30-50% less propulsion and regeneration power. 

The highest regeneration power is gained with fixed blade & adjustable pitch propellers and also with dedicated systems for hydro generator use, because they allow using a higher pitch/dimension propeller.

The regeneration feature is extremely suitable for catamarans because twin motors means double the energy generation.  Catamarans are also faster, which means that regeneration power capture is higher.