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scottkeen's avatar
scottkeen
Explorer
Jan 28, 2018

Onboard Generator or 2 Portable Generators + Solar + Battery

I have a 2011 Montana 347THT fifth wheel toy hauler and it has the gen-prep package with the shielded generator bay and wiring to a generator on/off switch inside the RV.

I just bought it used less than a month ago, and am looking for what power options I want to get for it. It came with a dealer-provided 12V 58Ah lead acid battery which will yieled 29Ah if I run it down to just 50%

I bought the RV with the intention of doing more dry-camping, boondocking and less campground-parks. My hopes are to go full-time and be largely energy independent.

I expect to follow-the-weather and run one 15K BTU AC only if I'm stuck somewhere in unbearable heat.

I'm considering my generator/battery/solar options with costs the same. Here's how I see it:

Option A: Onboard Generator - Gasoline
$3100 Cummins/Onan 4000 gasoline onboard generator (4000W rated)
$ 400 (est) gasoline tank under trailer between frame rails
-----
$3500
=====

Option B: Onboard Generator - LP
$3500 Cummins/Onan 3600 propane onboard generator (3600W rated)
=====

Option C: Portable Generator + Solar + Battery
$2050 (2) Honda EU2000i + EU2000ic with parallel kit (4000W peak, 3200W rated)
$ 640 Renogy 400W solar kit (PWM, upgrade to MPPT later)
$ 900 Renogy 12V 100Ah Lithium Iron Phosphate battery
-----
$3590
=====

I like the convenience and extra rated wattage of the gasoline onboard generator, and the convenience of the LP onboard generator and lower maintenance of LP vs gasoline.

But hard to argue with getting almost the same rated wattage from a couple of Honda portable generators and the option of only using one generator at 2000W (1600W rated) if that's all I need. Plus I would be getting a 400W solar kit and a much-desired 100Ah LiFEPO4 battery which I can run down empty, with more charge cycles and lighter weight than SLA.

I'm leaning highly to Option C, but the convenience and more power of Option A and B are really nice.

Your thoughts?

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  • scottkeen's avatar
    scottkeen
    Explorer
    Jan 28, 2018
    time2roll wrote:
    I would go bigger on the solar and battery for more independence. You can get more value in solar by going direct to the larger 24v panels and MPPT.

    epever 40 amp MPPT on amazon $150

    640 watts $280 at SolarBLVD.com
    Make sure these large panels will fit. Oversize shipping is expensive so check local solar installers for some surplus.

    Consider a small inverter (300w) to run the tv and laptop without firing up a generator. Running a large inverter (2000w) may take a 3rd or 4th battery due to high current loads.

    > Members Solar Installations With Pics


    Thanks, I was looking at the 24V installs by a couple of full-timers. One is actually doing 4x 300W 40V residential panels for 1200W total into a Victron MPPT charge controller then into a Tesla lithium battery bank. The Victron MPPT will convert up to 100V DC to 12V DC. He said he's going to install a "hybrid" inverter that takes power from multiple sources to meet the demand as needed and as available -- solar, battery, shore, generator. I think he's inverting solar after the batteries are fully absorbed.

    I have a 700W inverter now, and I'd like to upgrade to a 2000W inverter/charger, maybe after I get more batteries. My initial thought is to have 2x 100Ah Lithium Iron Phosphate batteries. At $900 each, I can't really sink money into 4 batteries right now.
  • scottkeen's avatar
    scottkeen
    Explorer
    Jan 28, 2018
    kerrlakeRoo wrote:
    Search the threads here and outside. The Champs have a good rep. Also I assume your Toy hauler has a fuel tank for bikes atv or whatever. Being able to use gas in the Genny instead of diesel may be more convenient since you already have a means of dispensing. And If the switching breaker was preinstalled with the Genny prep, so much the better.
    Those champs are about $850 or $900, so add a couple more panels and another of the lithium batteries. And you could still be ahead cost wise.


    My TH doesn't have gasoline tanks, it's a 2/3-size garage/office. Not a true "garage" but 2/3-size with tie downs in the floor but the rest of the space is an office. It's the exact TH setup I was looking for.

    The Champion 2000 (?) was reviewed on YouTube by Ray from Love-Your-RV and he did a great review on a pair of Champions stacked with the parallel kit in the middle. It looked like a great setup.
  • ford_truck_guy's avatar
    ford_truck_guy
    Nomad
    Jan 28, 2018
    I can compare options A and C as I went from one to the other..

    I started using 2 of the EU 2000’s with a 5 gallon extended run fuel tank... It got old getting there, getting the generators out and set up, hooking them together and setting up the fuel...

    I then purchased a 6500 LP version, although the LP version gets thirsty when running at max, it sure is handy, and that what I was looking for...

    We dry camp usually 2-3 times a year, and stay in campgrounds probably 95% of the time, so for us, it made sense..
  • kerrlakeRoo's avatar
    kerrlakeRoo
    Explorer
    Jan 28, 2018
    Search the threads here and outside. The Champs have a good rep. Also I assume your Toy hauler has a fuel tank for bikes atv or whatever. Being able to use gas in the Genny instead of diesel may be more convenient since you already have a means of dispensing. And If the switching breaker was preinstalled with the Genny prep, so much the better.
    Those champs are about $850 or $900, so add a couple more panels and another of the lithium batteries. And you could still be ahead cost wise.
  • time2roll's avatar
    time2roll
    Nomad
    Jan 28, 2018
    I would go bigger on the solar and battery for more independence. You can get more value in solar by going direct to the larger 24v panels and MPPT.

    epever 40 amp MPPT on amazon $150

    640 watts $280 at SolarBLVD.com
    Make sure these large panels will fit. Oversize shipping is expensive so check local solar installers for some surplus.

    Consider a small inverter (300w) to run the tv and laptop without firing up a generator. Running a large inverter (2000w) may take a 3rd or 4th battery due to high current loads.

    > Members Solar Installations With Pics
  • scottkeen's avatar
    scottkeen
    Explorer
    Jan 28, 2018
    Thanks for the replies.

    OK, I'll check out the Champion 3100. It's just that I've had a Honda EU3000is before and was so impressed by it that I was sold on the Honda gens. I'm trying to stay away from lead acid batteries mostly because of the weight compared to Lithium, and that Lithium can be fully discharged without damage.

    I can lift heavy things no problem. Convenience would be great, especially since my RV is already gen-prepped and wired for remote start.

    I'm trying to make this decision once (if possible!) and get it right the first time. I would like to:
    1) Use a generator as little as possible,
    2) Use solar as much as possible with a bank of high-amp batteries and a whole-house DC-AC inverter.

    I can only imagine using a generator when I'm somewhere and the heat is unbearable or there's not enough solar to charge my batteries.

    I'm pretty handy, so I don't mind doing the installation and electrical myself, I enjoy learning new things.

    I think in an ideal world I'd have option F (are we up to F now?) -- Onan 5500 onboard generator, one 2000W gasoline generator for more efficient light-demand use, 1000W of solar, and 500Ah of Li battery.

    Maybe the way to eat that elephant is one piece at a time. Maybe just start with 2 batteries and 400W solar and a whole-house inverter. I can expand the batteries and solar, and figure out what to do about the generator as I go.
  • Lwiddis's avatar
    Lwiddis
    Explorer II
    Jan 28, 2018
    “100Ah LiFEPO4 battery which I can run down empty,”

    I disagree unless you are willing to reduce the maximum number of cycles from about 5000. I’d stop at above eighty percent.
  • Lwiddis's avatar
    Lwiddis
    Explorer II
    Jan 28, 2018
    Even with your proposed lithium battery you’ll only have 80 AHs available for use. That’s not enough. And you don’t need 400 solar watts to recharge 80 AHs. The object with a solar system is to never use the generator except for AC and cloudy/rainy days. For less than $900 you should buy four Trojan T105s and have over 400 AHs with a useable 150-175.
  • Lantley's avatar
    Lantley
    Nomad
    Jan 28, 2018
    This is classic RV decision making. Too often we let price factor into our decision vs. just getting what is right for our individual needs.
    I have a 5500 built in Onan. It is certainly not the cheapest option.
    But it is convenient push button operation...Which is what I wanted.
    In the OP's case do you want:convenience,best bang for the buck, maximum power and run time, maximum ability/time to stay off grid? Are you able to lift heavy things and maintain a portable set up?
    What is most important to you and you alone? This is really not an at large group decision.
    The answer is more about how you intend to use your rig vs. price.
    In the RV game it's always cheaper to get it right the first time, but in order to do so your expectations and intentions become critical
  • kerrlakeRoo's avatar
    kerrlakeRoo
    Explorer
    Jan 28, 2018
    Option D.
    300 watts of solar, a 30 amp controller and in the genny compartment mount a Champion 3100, with remote electric start,.

    It will require some modifying to install, especially if you want to find a way to route the exhaust up like the Onan unit would, and you would have to decide where to mount your master breaker, but the total package shouldnt cost but $1800-$2000.

    Edit add on If you want to splurge, 4 GC-2 Batteries to give 430 Amp hrs of storage. $480 more.

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