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When does an electric repower pay for itself?
Enter your system and running costs. The calculator estimates the net upfront cost, your annual saving after electricity, and the year you break even — plotted as a cash curve you can read at a glance.
Your repower
Set your system and running costs — payback updates instantly.
Continuous power
≈ 40 hp diesel
3 kW80 kW
Battery pack
Usable LiFePO₄ capacity
5 kWh120 kWh
Hours motored / season
Sailboats 30–80 · trawlers 200+
10 h400 h
Diesel price
What you'd pay at the pump
€1.00€3.00
Electricity price
Shore power / home tariff
€0.05€0.70
Install approach
Payback time
72.3years
Until fuel + maintenance savings repay the net upfront cost.
Net upfront cost
€28,300
€28,300 gross · no grant applied
Net saving / year
€392
€409 diesel + €220 upkeep − €238 power
Net position at 10 yrs
−€24,383
still recouping
Diesel displaced / yr
227 L
793 kWh from shore instead
Cumulative cash position
Net €, electric vs staying diesel
Starts at the net upfront cost (below zero) and climbs by the annual saving. It crosses break-even at 72.3 years — beyond this 20-year view.
Where the upfront cost goes · Partial install
Battery pack24 kWh × €400/kWh
€9,600Motor + controller20 kW × €520/kW
€10,400Charger, BMS, monitoring, cablesBalance of system
€3,800Installation labourYard rate × hours
€3,000Compliance fittingsDisconnect, isolation monitor, logging
€1,500Gross total
€28,300Net upfront
€28,300Ready for the real numbers?
Turn this into a full spec & vendor-ready PDF
The configurator sizes your battery, DC & phase current, and cabling from your real boat — free to run.
Assumptions used
• Battery cost by tier: DIY €150/kWh, partial €400/kWh, turnkey €550/kWh installed (2026 LFP pricing).
• Motor + controller: €450–750/kW by tier — matched motor/controller pairs, not third-party mixes.
• Balance of system (charger, BMS, monitoring, cables & fusing) and labour are tier-based flat lines from typical retrofit budgets.
• ABYC E-30 fittings: dual disconnect, isolation monitoring & event logging — €800–1,500.
• Diesel at the shaft 0.35 L/kWh, duty cycle 65% of continuous rating, drive+charge efficiency 82%.
• Maintenance avoided €220/yr (oil, filters, impeller, belts, winterizing). Fuel & electricity prices are yours to set above.
• Grants: there is no EU-wide electric repower subsidy. National, regional, and municipal programmes exist with sharply different eligibility rules, so the grant rate above is yours to supply — check it with your national authority or harbour administration. Everything here is an estimate; confirm figures with vendors and installers.
Want it boat-specific?
Find your boat
Jump to the segment sizing guide for your hull — opens the configurator pre-filled with realistic defaults.
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Type a model name — we’ll point you to the matching sizing guide.