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Can you please tell me the size of battery bank i will need for a 57ft liverboard thanks.

Asked by: andy wakler  | 9.56pm, Monday 7 May

WW says:

The best thing you can do is run the electrical audit that is available to the left side of this page. That will help you work out your battery bank size.
However, rule of thumb: assuming you are continuously cruising and running the engine at least 4 hours a day: very simple (no 230V system and minimal power consumption 12V system) two 110Ah batteries. Add another battery if you have an electric fridge. For occasional 230V system through an inverter, add another battery to give you around 440Ah (which is around 200Ah in practice)
To ensure maximum usage, consider fitting an alternator controller to help maximise output from the alternator- standard regulators built into alternators can take a long time to fully recharge a battery.
If you are going to be almost permanently moored up, then choose a 4-stage battery charger, with an output of at least 10% of your battery bank capacity. So, if you have three 110Ah batteries, a 35A charger would be a good starting point.
Also, make sure that you maintain your batteries by regularly checking the electrolyte levels to ensure long life.

Mark Langley  | 7.23AM, Tuesday 8 May

If you are going to liveaboard, do consider the position of the batteries. Often they are stuck away in a cold and damp location under the back deck, and they will not perform very well when you need them most in the depths of winter. Much better to make a battery compartment as part of the living space.

Rupert Smedley  | 8.03AM, Tuesday 8 May

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