I chose to install an OceanVolt system…
I chose to install an OceanVolt system (AX-5 with 13kWh lithium batteries) on my Hallberg-Rassy in 2023.
The boat now manoeuvres exceptionally well, both at sea and in close quarters. Unfortunately, that’s where the positives of this ~£30,000 installation largely end.
The OceanVolt authorised installers in Spain lacked basic competence with marine propulsion systems. As a result:
- The prop shaft was misaligned and too short, almost fell out coming in to Lanzarote
- The propeller had the wrong pitch and wrong rotation for the drive train
- The shaft seal was the wrong size and leaked like a sieve
Responsibility was unclear throughout—installers blamed OceanVolt, and OceanVolt blamed the installers.
The project was delayed by months while the boat remained on the hard. One major issue (propeller direction) required waiting for a USB device to be shipped from Finland to Spain, which was "lost in transit". Even after resolving this, the system was never certified despite this being included in the scope I paid for.
The advertised distance of 40nm is more like 20nm, and even that under ideal conditions. If you see waves, it's far less.
Regeneration performance has also been disappointing. It was advertised to start from 5kn, but in practice requires closer to 6kn in very calm conditions. OceanVolt’s response was to question whether the keel was positioned ahead of the propeller - which, on your typical fin keel shaft-driven boat, it is. In other words, a fairly standard configuration appears... incompatible.
Even when exceeding 6 knots, regeneration shuts down after a few minutes due to some software issue. Resolving this appears to require a stable RJ45 cable connection onboard for a remote update, which is... impractical for anyone who's been to a marina or boatyard... with booking a 30min slot weeks in advance to get technical help, or OV tech support kindly offering up their lunch spots. Still no regen in sight.
Overall, while the dream of electric propulsion is close, the execution - from installation to aftersales - has been... frustrating and falls far short of my expectations for a system at this price point.






