Running a Washing Machine from Boat Lithium Batteries
Plan battery, inverter, water and generator capacity for running a compact washing machine on a liveaboard yacht.
A washing machine affects battery energy, inverter power, freshwater, watermaker production, drainage, generator strategy and hot-water energy.
Measure the Wh or kWh per complete cycle, not just maximum watts.
If one cycle uses 600Wh and you wash every three days:
600 / 3 = 200Wh/day average
The inverter still has to support the instantaneous load during the cycle.
Turn the appliance into a daily energy figure
The peak wattage tells you whether the inverter and BMS can start the load. Runtime tells you what it does to the battery bank. Treat those as separate checks, then include conversion losses and the loads already running aboard.
- Measure typical watts and realistic hours per day, including standby use and cycling loads.
- Check startup surge and maximum simultaneous current against the inverter, BMS and cabling.
- Test the result against a poor-solar day and preserve a reserve for essential navigation and safety loads.
Work out your own numbers
Inverter DC Current CalculatorWork out the DC current a marine inverter draws from the battery bank, and check it against the BMS continuous and peak ratings before you buy.Marine Cable Size and Voltage Drop CalculatorCalculate DC voltage drop and the minimum cable size for a marine circuit, and see why boat cable runs need far heavier conductors than people expect.
Related pages
Running Starlink from a Marine Lithium BatteryCalculate Starlink power consumption on a yacht and size lithium batteries and solar for Starlink Standard or Starlink Mini.Fridges and Freezers on Marine Lithium BatteriesEstimate daily energy for yacht fridges and freezers and learn how ambient temperature, insulation and duty cycle affect battery sizing.Autopilot and Navigation Power ConsumptionEstimate yacht autopilot, AIS, VHF, chartplotter, radar and navigation loads for offshore lithium battery planning.Laptops, Phones, Tablets and TV on a BoatEstimate digital and entertainment loads for a yacht lithium battery bank and reduce inverter losses with efficient DC charging.Running Induction Cooking from a Marine Lithium BatteryCalculate induction hob energy, inverter current and battery requirements for an electric galley on a sailboat or liveaboard.Watermaker Power and Marine Lithium BatteriesCalculate the energy required to run a yacht watermaker and integrate it with solar, lithium batteries and generator charging.