Repower sizing guide
40-foot sailboat electric repower
Bigger cruisers and offshore boats — where 96 V starts to make real sense.
Start sizing this boatPre-filled with realistic defaults
20–30 kW
Continuous power
30–45 kWh
Battery pack
210–310 A @ 96 V
DC current
30–55 nm
Cruise range
What this segment looks like
Why a 40 ft sailboat is a sensible repower target
At 40 feet and 9–11 tonnes, a sailboat needs 20–30 kW continuous to maintain 6 kn and meaningful headroom against wind and current. This is where 96 V bus voltage stops being optional — DC currents at 48 V become awkward to cable.
- 96 V halves your DC current vs 48 V — cable cross-section drops to manageable levels.
- 30+ kWh is the realistic minimum for offshore work with reserves.
- Shaft drive is still the most common 40 ft layout; saildrive options narrow above 25 kW.
- Plan for 5–7 kW shore charging to refill in a single overnight stop.
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Other segments
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