Beneteau First 30 (Mauric) electric repower: motor, battery and cable sizing

The Beneteau First 30 (Mauric) is a 9 m monohull with a 7.75 m waterline and 3,450 kg displacement. From those figures, the configurator's sizing model puts an electric conversion at 4 kW and 13 kWh on a 48 V system.

Boat data: sailboatdata.com — First 30 (Beneteau – Mauric), checked 23 October 2026

Motor power

4 kW

3.3 kW needed at 5 kn

Battery pack

13 kWh

2 h at full rating, with reserve

DC design current

139 A @ 48 V

cabling burden: easy

Range on that pack

10 nm

at 5 kn

Open the Beneteau First 30 (Mauric) in the configurator Compare motors for 4 kW

The boat

Length: 8.95 m
Waterline length: 7.75 m
Beam: 2.86 m
Displacement: 3,450 kg
Hull: Fin keel, rudder on skeg
Designer: A. Mauric
Builder: Beneteau (France)
Built: 1977–1981
Number built: 965
Original engine: Renault (model and power not listed)

Power needed by speed

Speed	Shaft power
3 kn	0.9 kW
4 kn	1.8 kW
5 kncruise target	3.3 kW
6 kn	5.7 kW
6.8 knhull speed	8.7 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 systemconfigurator's choice

139 A

design DC current · cabling burden easy · 35 mm² for a short run

96 V system

77 A

design DC current · cabling burden easy · 16 mm² for a short run

Motor lines that cover 4 kW at 48 V

Oceanvolt

SD saildrives (SD6 – SD15)

Saildrive · 6–12 kW continuous · 48 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 5 kn, which is 75% of the 6.8 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.
Beneteau has built three different boats called First 30. This page is the original 1977–1981 Mauric design; the 2011 Juan K. and 2025 Manuard versions are different hulls.

Beneteau First 30 (Mauric)

Common questions

How many kW does a Beneteau First 30 (Mauric) need for electric propulsion?+

About 3.3 kW to hold 5 knots — 75% of its 6.8-knot hull speed — so the configurator suggests a 4 kW motor. Power rises steeply above that: about 8.7 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 Beneteau First 30 (Mauric) need?+

The configurator sizes about 13 kWh of LiFePO4 for 2 hours at the motor's full 4 kW rating, with a 15% reserve and 80% usable depth of discharge — about 10 nautical miles at 5 knots. Cruising below full power stretches that.

Should a Beneteau First 30 (Mauric) use 48 V or 96 V?+

At 4 kW the design DC current is about 139 A at 48 V (cabling burden: easy) and about 77 A at 96 V (easy). The configurator picks 48 V for this boat: it stays on 48 V unless the 48 V current reaches its "very heavy" level.