200 watts of Uni-solar Flexable panels on roof
Morningstar MPPT Charge controller
Seriously leaning toward 4 Golf Cart Batteries (don't have them yet)
So with this setup, and given my energy usage, I should be able to get 4 to 5 days dry camping (with some heater running). Another note, I sure would love to not have to carry a generator, gas, and oil.
So in the event I had a string of rainy weather and got very limited production out of my solar panels, with a really good set of jumper cable, could I idle the truck for a few hours to recharge the battery bank?
Not saying this would be standard practice, but in a pinch would it work? Any issues I should be concerned about?
Yes, the jumper cables would work. The charging wire size is the usual restriction in trying to charge from the TV.
With dry camping, solar and truck charging you should have a way to check the state of charge, amp usage and amp input to your batteries.
Take a look at the TriMetric battery monitors.
2000 Sea Breeze F53 V10 - CR-V Toad
Some RV batteries live a long and useful life, some are murdered. Get a Digital Multimeter and Learn How to Use It
The unisolar panels are going to work fairly well even in cloudy conditions, as they convert diffused sunlight better than the average panel.
What I use to heat my 30' Bounder is a Olympic Catalytic heater. It will keep the RV toasty warm even at 40F outside, and below 32, I run the furnace a little bit to distribute the heat to the bedroom and basement, keeping it 70 inside with very little furnace used.
I have a 400 watt solar system, 4 golf cart batteries, and only need to run the battery charger a few hours in January. I live full time in the RV, yet have 120 volt hookups for the TV and microwave. Everything that runs on 12 volts runs from the solar system.
I think you will be fine without solar with 4 batteries for 5 nights, even with a little furnace used. With the solar, it will put back around 35 - 50 amp hours daily, and this will add to the 440 AH you started with, giving you at least 150 AH more after 5 days in the sun, up to 250 AH more in ideal sun.
My RV has a E-meter that carefully measures the power being used. My furnace is about 6 AH, and what really uses power is the refrigerator / propane detector/ CO detector. They total 35 AH per 24 hour period, and can not be reduced. Lights will probably only reach about 25 AH per day, water pump will move 120 gallons with 9 AH, so probably go the whole week with less than 8 AH. Furnace is 6 amps per hour, and might use 10 hours in 5 days?
I think you will be fine with the 440 AH + the 150 AH that the solar system is likely to add to your batteries in a 5 day/night camping trip.
As for the truck charging the battery, yes it is possible, what I would do is move the truck into position, leave it idle a few minutes, while hooking up the cables, leave it run say 5 minutes more, then shut it off. The truck and trailer batteries will equalize for the next 1/2 hour or so, and then start the truck and run it about 15 minutes to recharge all the batteries at maximum alternator output for that time. You will need to be above idle - say 1,500 RPM to get a good recharge. Or do this before going sightseeing, and the truck battery will recharge during the drive.
AS for as towing to recharge the fifth wheel, it will take many hours, and the solar system will probably put in as much power as the truck can. You are limited by the #12 wire between the truck and trailer, and the #12 wire in the power cord connection, and #10 ground wire. Upgrading that wiring is a good idea, to recharge faster during the drive.
However if you don't frequently drive between one boondocking place and another, then upgrading the wiring will not really do much for you. I normally drove to one place, and stayed there until time to go back to work. Yet if you drive to one lake, then another, then a third place before returning home, the truck can recharge the battery easy if wire is upgraded to #8 with a relay to prevent charging when the engine is off, and a "Anderson Connector" - a forklift battery connector rated at 50 amps that will transfer power more effectively.
I run into this frequently both here and afloat. The fact is that idling is not a good thing for an engine. Most engines will not adequately lubricate the parts that get splashed and sprayed when only at idle. Few engines will get the lube oil to and keep it at a temperature that will drive the trapped moisture (a by-product of combustion) out of the lube oil. Many parts of the engine will not be at or near the temperature they were expecting to be.
If you are going to do it about once a year when you get stuck in a week of bad weather, that is one thing, but if you make a steady plan of this it will not serve you well.
If you are wondering, I was an engine guy in Detroit for a lot of years before I went back to my boat work.
Matt & Mary Colie
A sailor, his bride and their black dog going to see some dry places that have Geocaches in a coach made the year we married.
A Ford with the 3G or 4G alternator will develop a potential of almost 100 amps at idle. Starting an engine cold and letting it idle for an hour would give you roughly 100 gross amp hour replenishment. I would certainly try to find cables with 2 gauge or larger conductors. Haven't looked at the newest vehicles but we used to jam a match book in the throttle linkage to keep the engine speed a little higher.