New Build Energy Questions

Joined
Apr 6, 2025
Posts
27
Location
Houston
We are building a new 21C and I would appreciate some thoughts on our logic. We also have a few questions and aren't sure how best to proceed.

Our situation is:
  • Family of four with two young kids
  • Anticipating 2-months travel each summer originating from Houston
  • Occasional weekend and week trips from Houston within TX/OK/LA/AR in spring-winter-fall
  • Plan to visit national and state parks and BLM land
  • Would prefer quiet natural areas vs RV parks and happy to dry camp or boondock if that's the best option but we don't foresee week-long boondocking on BLM land. At most it would be a couple of nights on BLM or several nights dry camping in a remote park site (such as Big Bend, for example) before moving to the next spot.
  • At home we sleep at 72 degrees and keep the house around 75-77 degrees during the day.
Cost is not a major factor so originally I was going to "max out" solar and battery and run as much on it as possible. I like the idea of minimizing propane and not having a generator. It sounds like that's hard to do though-if you want AC.

Given we will be traveling in the summer, AC is a must for at least part of the day and in some regions. I am struggling to figure out our path forward given we have no experience. I am leaning towards the minimum and adding (or not) later.

I am thinking of the following:
  • 3x 200W solar panels on the roof because this will be hard for us to do ourselves
  • Zap port
  • 2x 6v batteries
  • 2,000W generator dual-fuel (purchased seperate) (although I don't want to use this thing)
  • Coleman AC (although I want the Houghton)
While we have no idea how to build the solar and lithium components, we don't mind learning. My concern is, would I be able to build the following without major modification to the trailer:
  • 400-800Ah+ Lithium
  • Controllers, wiring, etc.
  • 3,000W inverter
  • DC-DC converter for tow vehicle charging
The advantages I see to DIY are:
  • Much cheaper than ETI based on what I've seen online for Lithium batteries
  • We can add a 3,000W inverter and more Lithium batteries to our traditional dinette than ETI will install. ETI will only install the 3,000W inverter with a U-dinette because they install it in the middle section.
The issue with ETI is that if I get their Lithium Ready package it requires (I think) the 1,500W inverter. Why buy the 1,500W if we eventually want a 3,000W to run the AC? Also, why buy 1 or 2 Lithium batteries if we can't add to those and must swap with new ones when/if we want to upgrade? That is wasted money.

So - my first question is can we install 400-800Ah+ with a 3,000W inverter and controllers in the traditional dinette? Presumably I would have to use both sides and route wires between benches? Could I put some equipment under the stove top?

We are also trying to decide on the fridge and AC.

We are leaning towards the compressor fridge since a lot of folks prefer it. We will have the 2-burner propane stove top. If we have a microwave, it'll be an inverter microwave we purchase and infrequently used. No tv - only phones, ipad, and two small laptops.

So - my second question is would the 2x 6v batteries be sufficient for the compressor fridge? Sounds like it would given we will not be full-time off grid and will have 600W solar. We will also be moving every few days. And if we upgrade to Lithium - no problem.

The AC is the tougher question. Both the Coleman Mach 10 NDQ and the Houghton are 13.5k BTU and require a 3,000W inverter to run off battery.

So - my third question is can I fit enough batteries in the 21C to run the AC? Is it a lost cause? I read conflicting info on the total amp usage. The specs say 10-15 amps but then people say you'll use an entire 100 Amp battery in an hour - which makes no sense. I would like the AC to run off battery enough to cool it down for lunch and evenings before bed. Maybe run a bit while we are in bed. We don't need it 65 degrees all day... There could be some days we are stuck in side and it's hot - but we could keep it at 77-80 and deal with it for those few times.

If the AC on battery is a lost cause - then I don't really need much lithium or the 3,000W inverter right? Which means I could just have ETI install a 1,500W and one or two lithiums and while overpriced, we wouldn't have to DIY.

Lastly, ETI states the Coleman can be run off a 2,000W generator while the Houghton requires a 3,000W generator. I've read discussions and have no idea what to think... Some say the 2,200W generator will run a Houghton 13.5K, others say just add a hot start, others say get the biggest gen you can afford. Our issue is that our tow vehicle is a Lexus LX 570 and I'm not excited about lifting and loading a generator in the back. The 2,000W looks manageable but the 3,000W would be a PITA and take up a lot of space which we are limited on. I would just go with the Coleman but the Houghton is rated significantly lower dB and having a quiet AC is definitely preferred. I've seen some 3,000W gens that match the 2,000W gen size - but those seem to be anomolies? Others connect two 2,000W gens which seems a bit nutty. And then I read that the AC will burn 20 lbs of propane in 8 hours.... So that's say 2 days max. Are people filling up propane/gas every two days to keep their ACs running???

So - my fourth question is which AC? Coleman or Houghton? Am I forced into the Coleman if I don't want a 3,000W generator? If I can run the AC off Lithium - then do I need a generator?

So - all of this unknown has led us to max the roof solar, choose compressor fridge, 2x 6v and upgrade to lithium later, Coleman AC, and 2,000W generator. My hestiance is 1) can we build out the lithium without major headaches, and 2) am I going to regret the Coleman vs Houghton?

Also FYI - We are adding the underside foam insulation so I'm concerned we wouldn't be able to run wiring under the trailer if needed for the solar/batteries in the future.

Thanks and sorry for the long post!
 
Any thoughts on whether this would be doable? Dimensions are correct and @sackettd fit these LiTime 230Ah in their E19 in this configuration. I just drew a giant box for the misc. hardware. And I would need to run wiring in front of the wall and cover it.

I am second guessing because ETI requires a u-dinette for the 3000W inverter.

Why would this not work?

Screenshot 2025-04-19 at 9.17.36 PM.png
 
I'm not understanding running the wire in the front of the wall. Don't you have a panel in this area. If so, it's easy to run wires behind it.

Ron
 
I don't know (I'm in the ordering process). I asked ETI if there was a panel of sorts at the base area of the wall and they said no. Maybe they misunderstood the question.

I was surprised there wasn't a way to run wiring back and worth - I had expected there to be a stock way.

I'll ask again next week.

Thanks
 
My Gen 1 had a panel on the front wall, equivalent to the one on the rear wall of a 21C. In both I've run wires side-to-side. Unless Gen 2 19s are different you should be OK.
 

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Do you need to line all batteries up for cabling? Or, can you separate them like I show and just have double the cabling?

Any issues having all the batteries and inverter on one side with regards to weight and balance on the trailer? Is one side better than the other?
 
Take a look at Johnny Hung's trailer. You can find a YouTube video on the ETI website, or you can just google "Johnny Hung Escape Trailer". If you want to run a compressor fridge and an air conditioner - both probably a good idea in Texas - as well as other electrical like the heater, coffee pot, etc. you will need to seriously up your solar (again see Johnny's trailer) or go with a generator. If you can get by w/o AC, then you will probably be fine with a large battery bank (500 to 600 Ah capacity), an extra solar panel or two in addition to the two you can order from ETI, and/or a portable solar panel you can plug in to the zamp port (don't forget to ensure that is included in the trailer).
If you go with AC, install a "Soft Start" on the unit. Quite a few of us have and they really help as you can carry a small inverter generator and run the AC from that. We have the Honda 2200i and it does the job nicely, is not very heavy, and does not take up a huge amount of room.
 
@DT6 thanks for the reply. I've watched Johnny's videos and read most of the threads I could find. ETI will install three 200W panels, so I will have those plus a portable panel. So maybe 800W total without doing what Johnny did and stacking the panels.

We will not have a coffee pot. Maybe a toaster and occasional microwave use. Propane stove.

If I can get the Houghton 13.5k BTU, install a soft start, and use the Honda 2200i, that would be ok. I just read mixed info on running a 13.5k AC with that level of generator even with soft start.

I've also read there is a new inverter that lets you split the load across batteries and generator, so maybe that would ensure the generator can handle the AC while extending usage between shore power?

Thanks
 
This example may help:
My wife and I camped (no hookups) in sunny Big Bend NP in late February this spring for 10 days.

My load was moderately heavy - inverter powering a coffee pot, toaster and electric blanket. 12 VDC powering - compressor fridge, 1-2 hours of furnace, water pump, misc. phone, computer chargers & lights.

My solar was 350 watts of portable, oriented 2 times per day, plus 160 watts flat on the roof. All panels received full sun starting around 10 AM. Charging amperage according to the GoPower solar controller dropped to near zero around 1-2 PM, indicating batteries full.

Bottom line - our average daily power withdrawal was offset with about 3-4 hours of charging. (I don't have a AH monitor so my numbers are best guesses.)
 
I just finished the DC and AC power set up in our 2023 E19.
I won’t go into all the details, which there is a lot! But it took quite a bit of engineering and work. First, you really need to figure out what are your minimum requirements, and then ad some extra or a bunch of extra.
The larger the Watt hour requirements the greater the space and money requirements. Good ventilation for the equipment is also needed.

I installed my system with the intention of being able to boondock for at least a day and have air conditioning all night long, I think I reached that goal and perhaps more, but still need to do field trials in a hot climate.

I went with Houghton 9.5 and installed a soft start before installation. The unit works great and is very quiet. I run it off a 2000 watt Renogy inverter supplied by three LifePo4 batteries with 860 Ah combined. The AC draws @65 amps from batteries when the compressor is running and between cycles 6-7 amps with just the fan. One caveat is that the three 80 watt Lensun flexible roof mounted solar panels are helping, but being flat they are not efficient, in he first week of April in So California I was able to get 165 watts from the panels.

The system takes a lot of room and I ordered my 19 with the U shape dinette because I knew I was going to be doing a system and wanted it all to fit under the dinette, as it turns out it takes a lot of room for my system, but I got it all to fit and stlll have the storage under most of the passenger seat. Also, automatic temperature controlled fans blowing in and out of the compartment
I think the E21 will have more room, and that will be a good thing! Anyway, do as much homework as you can and ad a whole lot for what you don’t know that you will probably need.
Thanks
Bill
 

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I One caveat is that the three 80 watt Lensun flexible roof mounted solar panels are helping, but being flat they are not
I find my swiveling tilting portable panel is far more efficient. Starts producing earlier, produces more during peak hours and keeps going longer.

A good argument for having a portable panel and keeping it optimized.

Ron
 

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@Ron in BC i was debating getting the ETI panels because they can not swivel... My thought was am i better of installing something later that can be adjusted. But then i'd be not getting anything and stuck trying to DIY everything. Presumably i can use their mounts to make them adjustable in the future - if i need to. So i start with the basics and then modify, if needed.

I'm surprised they don't offer a mount with basic one-direction adjustments. But that is easy to say about a lot of these "nice to have" features and ultimately it's more cost/complexity for them.
 
And presumably you could combine with something like this:

Amazon.com

I saw one video where an Escape user had them actuated, but that was the only time.

Is there 12V access in the roof to provide power or would I need to ask or DIY that? Can you come off the AC somehow (I know zero about electricity...).

Thanks
 
I'm surprised they don't offer a mount with basic one-direction adjustments. But that is easy to say about a lot of these "nice to have" features and ultimately it's more cost/complexity for them.
I made mine tilting and swiveling, as the saying goes, because I could. And having a milling machine to make the quadrants helps too. But several members have done DIY tiliting mounts for their panels and there's still significant gains to be made.

Maybe Jon V. will post photos of his.

Ron
 
Is there 12V access in the roof to provide power or would I need to ask or DIY that? Can you come off the AC somehow (I know zero about electricity...).

Thanks
It depends which fridge you have. For compressor fridges without a roof vent, it's more difficult to run power up to the roof. It would involve drilling a hole. No biggie but with an absorption fridge with a roof vent it's very easy. Under the vent cap and drop it down the fridge chase.

Ron
 
If I order the following, what is involved in upgrading to a 1500W or 3000W inverter with lithium batteries?

- Solar panels (3x 200W)
- Single 12V battery
- Lithium Ready (DC-DC charger)
- Compressor refrigerator
- Houghton AC 13.5k
- Propane cook top

So starting without an inverter or lithium batteries.

Will the upgrades all be in the battery area (inverter, wires/chargers, switches, fuses, etc.)? Or will i have to change wiring throughout the trailer?

We would prefer to do this to save money on the inverter and batteries since Escape seems to require 2 lithium batteries if you purchase the 1500W inverter - and we really would rather jump to the 3000W inverter anyway. If it is physically straightforward to upgrade, then we are good DIYing or getting a consultant to help. But I'm concerned if we have to change out wiring throughout the trailer.

Thanks
 
Wondering how you ended up? I’m thinking similar, but don’t like their batteries. I want two 270 Ah lithium, the compressor fridge, convection microwave and 12volt air conditioning. Have not asked Escape yet beyond batteries - and they pushed back on those.

TIA. Cheers
 
We did the following:

- No inverter
- Dual 6V lead acid
- 3x 200W panels
- Solar port wired to charge controller
- Lithium battery ready
- Houghton
- Compressor fridge
- No microwave (but microwave ready - we will buy our own)

Our thinking is that we will add our own 3,000W inverter and lithium batteries to optimize battery storage, space, weight, and cost. The options on the market are much better than what Escape offers, presumably due to them being required to box each battery and source from one supplier.

We also have the traditional/full dinette. They would not install a 3,000W inverter in that setup, so we were forced to either buy the 1,000W inverter or DIY a 3,000W. It just seemed a waste of money/value to pay so much for a 1,000W when we could practically DIY a 3,000W for not much more cost.

We also bought the 2,200W Honda and will convert it for propane. We will see how much we use the AC when not on shore power and if solar is enough. Cost is not a big factor for us, so we will probably max out the battery storage even though a good bit of it will only ever be used for AC...

Most of our travels the next 10 years will be summers with a base in Houston, so I just expect that AC will be a big focus and wanted a lot of times when we don't have shore power.
 

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