Selene 42 Voyager electric repower: motor, battery and cable sizing
The Selene 42 Voyager is a 13.8 m monohull with a 11.71 m waterline and 18,144 kg displacement. From those figures, the configurator's sizing model puts an electric conversion at 25 kW and 80 kWh on a 96 V system.
Boat data: Selene — Selene 42 Voyager brochure, checked 23 October 2026
Motor power
25 kW
16.1 kW needed at 6 kn
Battery pack
80 kWh
2 h at full rating, with reserve
DC design current
482 A @ 96 V
cabling burden: very heavy
Range on that pack
12 nm
at 6 kn
The boat
- Length
- 13.77 m
- Waterline length
- 11.71 m
- Beam
- 4.42 m
- Displacement
- 18,144 kg
- Hull
- Monohull
- Builder
- Selene Ocean Yachts
- Original engine
- Cummins diesel — 230 hp
Power needed by speed
| Speed | Shaft power |
|---|---|
| 3 kn | 3.1 kW |
| 4 kn | 5.8 kW |
| 5 kn | 9.9 kW |
| 6 kncruise target | 16.1 kW |
| 7 kn | 25.4 kW |
| 8 kn | 39.4 kW |
| 8.3 knhull speed | 44.7 kW |
The configurator's power-per-tonne heuristic, not a tank test — real boats vary by about ±25% with hull form, fouling, sea state and propeller. Near hull speed the power climbs steeply.
48 V or 96 V
48 V system
868 A
design DC current · cabling burden very heavy · 400 mm² for a short run
96 V systemconfigurator's choice
482 A
design DC current · cabling burden very heavy · 240 mm² for a short run
Motor lines that cover 25 kW at 96 V
From our motor comparison, matched by power and system voltage only — check drive type and fit with the maker.
What these numbers assume
- The published displacement. Your boat loaded for cruising is heavier — use your own figure in the configurator.
- Cruise target of 6 kn, which is 75% of the 8.3 kn hull speed.
- A shaft drive (assumed — the source doesn't say; a saildrive adds about 4%).
- A pack sized for 2 hours at the motor's full rating, 15% reserve and 80% usable depth of discharge.
- Selene has built several 42 ft models; this page is the 42 Voyager (aft cabin). The brochure gives displacement as "40,000 lbs (18,9 t)", but 40,000 lb is 18.1 t — we use the pound figure.
Selene 42 Voyager
Common questions
How many kW does a Selene 42 Voyager need for electric propulsion?+
About 16.1 kW to hold 6 knots — 75% of its 8.3-knot hull speed — so the configurator suggests a 25 kW motor. Power rises steeply above that: about 44.7 kW at hull speed. These are estimates from the boat's published waterline length and displacement; real boats vary by roughly ±25%.
What size battery does a Selene 42 Voyager need?+
The configurator sizes about 80 kWh of LiFePO4 for 2 hours at the motor's full 25 kW rating, with a 15% reserve and 80% usable depth of discharge — about 12 nautical miles at 6 knots. Cruising below full power stretches that.
Should a Selene 42 Voyager use 48 V or 96 V?+
At 25 kW the design DC current is about 868 A at 48 V (cabling burden: very heavy) and about 482 A at 96 V (very heavy). The configurator picks 96 V for this boat: it stays on 48 V unless the 48 V current reaches its "very heavy" level.
More on this size of boat
Trawler yacht electric / hybrid propulsion