Battery

I'd get two 6V's from Sams club or Costco unless you can get a deal on Trojans somewhere. I bought two from Sams a couple of years ago and it was around $190 out the door, core and tax included. The 6V's will be the most power for the money and will take some rough treatment.

If you're going to be Festing continually, I'd suggest to look into solar. It is quiet, easier, and you don't need any fuel. You can take your genset along but if the sun shines, you may not need it.

With a single 12 volt battery, you'll need to run the Genny 2-4 hours daily, after the first 24 hour period of battery use. Use a volt meter @ the battery & check it occasionally.

Thanks everyone for the information so far. The trip will be 4.5 days for a music festival. The trailer has all LED bulbs. The fridge and water pump will be used.

I do have a generator, but its an 65 dB model and don't want to use it more than 20 minutes or so a day.

My son has one boondock trip to Colorado this summer for 10 days. We installed two 6 volt batteries and led bulbs. His converter will only go to 13.6 so he is using my Megawatt power supply so he can do 14.8 volt charging with a Honda 2000. While we were at it we installed a blue seas battery switch so he could easily shut everything off while in storage. He trashed a couple batteries because it was a hassle to remove the battery cable all the time.

If you consider the power supply route I would buy a Meanwell not a Mega watt, get the 15 volt model with an operating range of about 13.4v or so to about 17v. This will let you have a charging source that will go to a high enough voltage to equalize at times. I consider led a must. He bought cheap ones on ebay for $20.00 for 10. He figured he would give them a try and has not had any problems. Research led as I have notice people complaining of over heating.

If you don't have LED bulbs in your TT and this is a one-off type trip, consider using 1-2 LED camping lanterns supplemented with puck lights.

Probably your best bet for more DC power for $200 would be to install two each 6VDC GOLF CART Deep Cycle Batteries wired in series. COSTCO sells them for around $90 each plus core value.

This will give you around 220AHs of battery capacity.

The standard issue 12VDC Interstate Deep Cycle Battery that most trailers comes with only gives you 85AHs

A 105 to 110AH deep cycle 12VDC battery will cost you around $150 plus.

Running standard automotive type incandescent lamps and fan on your heater will eat up a single battery in one day of use. These need to be changed out to LED lights. It would be best to have a smart mode charging system as well.

If you run any deep cycle battery lower than 50% charge state and not re-charge right away it will do internal damage to your battery requiring replacement soon.

Its alittle more than just showing up at the off-road camp sites. You need to make a few changes to be able to survive it for a few days and do any harm to your battery setup.

My 255Ahs battery bank does us just fine camping off the power grid but I have to re-charge every morning using my 2KW Honda Generator (when allowed to run it) for three hours to re-charge my battery bank using smart mode charging back to its 90% charge state so that we can do the next day/night run off the batteries. We do this 50-90% charge states for about 14 days before we have to fully re-charge the battery banks to its 100$ charge state which takes around 12 hours or of running the generator.

Adding solar panels to the trailer would only reduce our generator run time down to around one hour verses the three hours required.

Its all second nature to us now camping off the power grid.

For us it much more enjoyment camping off the batteries verses just going somewhere and plugging into their 30A Power Pedestal.

Just some of my thoughts
Roy Ken

If you are going to live large using the furnace all night and lights up late playing and entertaining.... your charge will last but 24 hours max.

How many nights will you be camped?

Do you or anyone in the group have a generator? For generator charging you may need to update your charging system. LED lights and 100 watts solar will go a long way no matter what battery you choose.

Otherwise I recommend 2x Group 27 from Costco, Sam's Club, Walmart for best value.
If you will be doing this more often consider a pair of GC2 Golf Car batteries. These a 6 volt and need to be wired in series.
Either way should be under $200

Describe your "off the grid trip". One day? two days? 1 week?. What do you plan to use other than lights? Furnace? Water pump? Fridge? More info supplied will get you much better results. Good luck with your quest.

Depends on what you want to be able to use and for how long.
Two big things I think are:
1. What kind of lights do you have (LED or incandecant)
2. How do you plan on recharging the battery you buy.

I do a 7-10 day trip off power, but I have a 1000W inverter and plan on getting solar before this years trip. I have a group 31 battery which fits in your price range...