DIY electric drive 3 kW

First of all, a few important notes that you should definitely pay attention to.

3 kW electric drive for a 25-person sailing boat Make 25 (all pictures from

PePeSail from the Segeln-Forum approached us and pointed out his DIY project to install an electric drive in a 25 foot sailing boat and asked whether we would like to publish it here. In the project, a built-in diesel was exchanged for a 3 kW electric drive. The renovation was done on our own. To do this, the electric motor had to be coupled to a new cardan shaft system via a gearbox. Some lamination work also had to be carried out in the boat hull to accommodate the shaft bearings. The whole project is described in detail here:

The project started in the Segler-Forum. Many fundamental considerations and questions about e-propulsion on boats were also discussed there:

Here is a video about the running electric drive:

Technical marginal data for the project:

  • 3 kW brushless e-motor 48V with electronic control
  • Toothed belt drive
  • 4x 12V 60AH LiFePo4 batteries
  • 2x 18A charge regulator
  • Cardan shaft with through bearing



Shaft system and shaft passage

Battery box 4x 12V 60Ah LiFePo4 batteries with balancer