Inverter Systems may be used as an alternate power source, but in many cases the vessel will require more power than is available from the inverter.

Large Inverter systems engineered to supply the ship with ample power, equal to genset output, will need large banks of batteries. The amount of power and the duration of time the power is needed are critical factors in the design of these systems.

Often inverters are used to operate critical systems while at anchor and at night. Some inverters interface with generators and start them automatically when battery power is low.