Thanks for all of your excellent contributions to the forum!  I've learned so much reading your thoughtful entries.  

My wife and I are soon to purchase a 172 and I'd greatly appreciate your insights concerning the DC power supply.  

Background:  After 7 years of moderate-to-critical struggles, our Make-a-Wish child is doing much better...able to take trips without a lot of special equipment...and ready to get out into the world and make up for lost time spent in hospitals and at home.  :)  

Given our family circumstances, we're not "campground" people.  Crowds, strangers, and especially environments where people are drinking are things we need to avoid.  Therefore, we expect to primarily "dry camp" whenever possible...dispersed-camping sites approved by the state DCNR...the quieter, "no hookup" sections of state parks where a small TT is permissible, dispersed sites within the nearby national forest, etc.  

(Disclaimer: I know that I should learn by experience.  I know that I should "get out there and camp" before worrying about mods to our unit.  I know I'm being impatient and probably not as fiscally responsible as I could be.  I also know that we love our kid and want to make our unit as functional and reliable for him as possible, within our ability.)  

A few things regarding which I'd appreciate your insights/expertise:

A) I know we're going to have to purchase a generator if we want to run the A/C unit.  This is important, because our son requires a consistent, temperature-regulated environment.  It looks like an "inverter generator" is the way to go...quieter for him...more efficient...etc.  I've read that the pod A/C unit draws anywhere from 1200 to 1800 Watts...would you feel comfortable with a 2000W generator?  2200W are also feasible for us if you thought it would make a difference.  The 3000W+ are just not "in the cards" for us.  

B) Regarding the battery...I hate to be wasteful, but I want something dependable that I don't have to worry about, provided I follow maintenance protocols.  I'd also prefer to stick with 12V batteries (and not the dual-sixes), as one of them already comes with the unit.  

If the truth is that buying a 2nd battery will get us safely through a 4-5 day trip without obsessing over DC consumption...and that's it...I'd rather take that route.  When the first one hits 50%, pop it out, replace it with the other, and begin re-charging the first one as soon as possible?  

What about a dual-12V configuration with two 12V batteries wired in parallel on the tongue of the trailer?  Twice the capacity...still 12V.  Does this invalidate the on-board battery monitor?  How would it know that you've got "twice the capacity" versus the original, single battery?  Have to monitor by hand with a voltmeter instead of using the on-board indicator?  

Leave it as a single battery with a 120 Watt solar panel attached throughout our stay?  Could it continuously re-charge the battery while the battery is in service...or would it have to be disconnected from the DC system of the TT first?  Is this a viable means of prolonging (observably) the "safe operating 50%" of the battery?  More fuss than it's worth?  

I'd really appreciate your thoughts on this.  I want to find the most reliable, no-fuss way to make sure that we're going to make it through a long weekend without ending up in the dark or needing to head home unexpectedly.  Our situation is definitely not in the mold of "2 careful, energy-conserving adults"...we have 2 kids and a light will get left on at some point...the water pump will get left on for an afternoon before I notice it...someone will leave the fan running in the lavatory, etc.  

Money is a consideration...but if putting $300-$500+ into our power system makes it "fool-proof" for us and keeps us out there as a family, it would be the best money we ever spent.  

Thanks!  

If you just want to be able to recharge your battery, then a 1000 watt inverter generator is a much lighter, cheaper, very satisfactory option.  But, please, stick with an inverter generator (regardless of the brand) - you're running electronics, not power tools.

Yes, you can simultaneously charge while using a battery.  Doesn't matter if its solar, generator, or from an electrical outlet.

Solar is great - depending on your latitude (obviously, its more effective the farther south you are), the weather, and your camping style.  If you like camping in the woods, or in a frequently rainy/overcast area, then solar may not be for you.  When sizing your solar, consider that you'll need a system thats able to replenish 20-30 amps per day.

On a group 24 battery, expect to get 3 days in the summer, 1-2 days in the spring/fall (when you're using your furnace).  Heavy furnace use, or if you have other electrical draws will also diminish battery life.  Also, swap out your interior bulbs with LEDs.  Its a bit expensive - but its well worth the effort.

If you're considering dual batteries, remember: both batteries MUST be of the same manufacturer and age.  A pair of 6 volt golf cart batteries are a very effective, very easy, very no-fuss solution for off-grid camping (which will supply 5-6 days of power).  BTW, if you're concerned about the cost of replacing a piddly little $70 stock battery - woooo, boy are you looking at the wrong hobby.

I'll go with the LED replacement for sure.  

I agree about the redundancy and limitations of the solar...thanks for your excellent points.  Glad that Craig suggested the smaller inverter generator...sounds like that's just what we need.  

I'll look back into the dual 6V battery configuration.  The $70 stock battery is not a big deal...I had been under the impression that the Amp*hour rating on it was much higher and that I was dealing with a $250+ battery...which would be wasteful to merely toss aside.  

Thanks again and happy travels!  

Wow!  That's the stuff right there...thank you so much!  Helps to really understand what you're contemplating!  What a great resource!  

Yes I have - with a Supco SPP6 ( http://www.amazon.com/gp/product/B000LDPI26/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=B000LDPI26&linkCode=as2&tag=lo02f-20 - link ); its a direct replacement and it took longer to pull the ladder out of the garage than it did to install it.  Note: the SPP6 is the appropriate one for my A/C - different models over the years may well have different requirements, so you'll have to do some research.

I have a six year-old Hyundai 2200 watt peak / 2000 watt running inverter generator that it works quite well with.  I like my old Korean knock-off genny and was glad that a cheap start-cap was able to keep it in service.

I'm hoping the weight is a good extra deterrent to keep anyone from taking my Honda!  Eventually I need to buy or build an engine hoist so I can mount it w/o help from my 12 year old daughter.  I'm fortunate that she is very strong.