Hi Albert Dave here at Port Boat House. I just thought I would send you a quick note. As you have a battery bank of 4 house batteries you do have a larger storage bank during the night plenty for the average, when the solar panel isn't feeding it back I always recommend to limit the use of all electrical systems while on the hook including turning the Garmin screen off and turning down the fridge settings. I would not recommend using your main engine as a alternator source just while sitting there as the alternator really only charges well while under a good load and underway, there is more potential damage that this can occur including putting hours on the main engine, sucking up debris while just sitting there in the high speed pick up and added wear to the impeller. Those bigger diesel engines really do not like to idle for longer durations of time as they will tend to collect carbon in the turbo etc. If you are not planning on running the main engine for a couple of days on the hook. I would suggest getting a small portable Yamaha 2000 watt generator that you can plug into your shore power cord as a secondary source and this will run the water heater as well, it is light portable and a great source of secondary power. If you want to run all systems on board. You will find the little generator is quiet and has sine power which is a clean wave that you can run TV,s and laptops with no risk of surging. I hope this helps
PS it would take about 15 minutes of running the boat around to get the 11 gallon hot water tank up to temperature to have a good long shower
