Since we’ve lived in San Diego the power at our marina has gone out 3 times. The latest was while I had the coolant pump removed for an overhaul so I wasn’t able to run the engine to recharge the batteries if they got too low. The only problem we could have had was a dead battery on the boat and not being able to start the engine. If I’d have needed to charge the batteries real bad I could have rereouted the water hoses from the saltwater lines to the engine block and used that to cool the engine, then flushed out all the saltwater after the pump was reinstalled.
Luckily the power came back on the next day and we were back in business. The only thing we had to worry about was our new 115VAC fridge we bought at Wal-Mart. Soon we’ll have a new boat and we won’t have to worry about that because there will be enough battery bank and power to run onboard refrigeration.