Converting RV to solar

[BigRockSpeaker]

Hi everyone, been following and posting on this forum for many years, and for the last five years I have had my own build, a converted cargo trailer, where I knew everything inside and out because I put it there. Just recently purchased a 2001 Class A, which still has a 2-way fridge and a single lead acid house battery. I want to begin the process of 1) upgrading to a LiFePO4 battery bank, 2) putting solar on the roof and adding the controller and inverter, and finally 3) replacing the fridge with a 12V compressor fridge. I'd like to do these in stages. My question is: can I just pull the lead acid and pop in the LiFePO4s? I don't have experience with how the non-solar motor home electrical system works.

 

[afblangley]

Before you start yanking stuff out, do the math on how much power you need to use the RV in the manner you want. The typical class A uses way more power than can be created via solar and stored in a battery bank. In mine, the biggest energy hog isn't the house sized fridge, it's the 3 rooftop ACs (which are needed to keep the space comfortable). Add in electric water heating, numerous fans, lights, TVs, pumps, etc. Even a large battery bank would be depleted within a few hours. Running the onboard generator (plumbed to the diesel tank) is the most cost effective way to create power. It's stored in a 300Ah battery bank. Last year, I replaced the lead acid batteries with AGM. Switching to lithium would have required upgrading the controller. Doing all this (a cost of $5k) still wouldn't eliminate the need for a generator. From a financial perspective, upgrading to lithium wasn't worth it.

There's a reason why lithium has taken over the class B segment but made only minor headway in the Class A market. Everything in my camper van can be powered for a couple of days from its 300Ah lithium battery. Spending money on it in lieu of a generator makes sense.

 

[BigRockSpeaker]

Before you start yanking stuff out, do the math on how much power you need to use the RV in the manner you want. The typical class A uses way more power than can be created via solar and stored in a battery bank. In mine, the biggest energy hog isn't the house sized fridge, it's the 3 rooftop ACs (which are needed to keep the space comfortable). Add in electric water heating, numerous fans, lights, TVs, pumps, etc. Even a large battery bank would be depleted within a few hours. Running the onboard generator (plumbed to the diesel tank) is the most cost effective way to create power. It's stored in a 300Ah battery bank. Last year, I replaced the lead acid batteries with AGM. Switching to lithium would have required upgrading the controller. Doing all this (a cost of $5k) still wouldn't eliminate the need for a generator. From a financial perspective, upgrading to lithium wasn't worth it.

There's a reason why lithium has taken over the class B segment but made only minor headway in the Class A market. Everything in my camper van can be powered for a couple of days from its 300Ah lithium battery. Spending money on it in lieu of a generator makes sense.

Thanks AF. I wasn't planning on running anything else off the batteries except for the fridge, water pump and the lights; everything else will run off propane, and I would continue to run the Jenny for the AC. Already started upgrading all the lights to LED. I just don't like driving down the road with the propane fridge on, plus I can't see the point of having a huge battery compartment with a single lead acid battery that you can only drain to 50%.

In my cargo trailer, I run everything - fridge, lights, fans, etc - off my 400w panel and now outdated Bluetti AC150

 

[INTJohn]

afblangley’s post is correct. In theory from a use side of the lithium battery you can power anything with one that you can power with a lead acid or agm. The problem from a plug & play stand point is on the charging of the battery side.

One needs a charging capability that is compatible with/for lithium. This includes controller that is lithium compatible from both solar and vehicle charging compatibility.

Newer built rv companies are beginning to incorporate this but older ones are not set up for it so as stated previous post probably better to go with agm’s un less one has the means and really wants to go full blown LiFePo4 for their class A or C.

There are numerous pro & con links re the rv change over from lead acid to lithium on Google.

INTJohn

 

[bullfrog !]

What I did that works for me is to buy a Delta ll power pac that charges from a 12 volt DC or 120 volt AC source to supplement my older AGM battery bank.

 

[BigRockSpeaker]

What I did that works for me is to buy a Delta ll power pac that charges from a 12 volt DC or 120 volt AC source to supplement my older AGM battery bank.

Thanks, all, I have decided to forego the lithium conversion and instead upgrade to a 200 Ah AGM. I can still supplement with my solar and my Bluetti when not on shore power

 

[maki2]

good choice just to upgrade to an AGM battery. It is simpler than upgrading the charger unit in your motorhomes converter to one compatible with lithium.

 

[NctryBen]

I put in lithium over the agm’s… changed the converter to one that’s compatible with lithium. Only time I need to plug in is for air or microwave… or if the sun doesn’t ever shine. 12v full size fridge… propane furnace can be a draw so I added battery… I can be totally off grid with amenities! Changed all lights to led… 12v tv with dvd built in. Like I say… plugged in now for air conditioning at sons. New grand baby so it’s not like old grandpa can just head for the hills. Haha!
Oh, I do have a generator I can run my air and whatever if needed… thanks to kids at Christmas last year.

 

[RvNaut]

he typical class A uses way more power than can be created via solar and stored in a battery bank.

This is 100% incorrect.

I have 2004 class a with 1400w of solar, an All-In-One and a 15kw battery I built. $5000. It supplies my current needs, but will be expanded. I draw about 350 watts avg 24/7.

There is lot to it and I didn't do it without a lot of planning and study.

Roof space is critical. I was able to source 6 panels from SanTan solar that I could fit on the roof, for a measly $423.

The All-in-one was $900 and can handle up to 4800w of solar.

I built my own battery. I elected to build a large one to cover any future expansion of the system, which is in the plan. $3000

A 48->12 volt converter....

I am done with step one, of integrating the new with the old, ditching a generator except for rainy day charging.

Long term, I will replace the furnace and the roof A/C with a Mini Split. The AIO can put out 3000w, and running the roof A/C now puts a big load on it, but the MiniSPlit will take that down to 1200w....

Here is a amateur schematic of my setup.

 

[tx2sturgis]

This is 100% incorrect.

I dont see the statement as 100% incorrect, because afblangley DID say 'typical RV'....

And an RV with $8,000 to $10,000 worth of added-on lithium batteries, solar panels and associated inverters and other hardware for harvesting and storing large amounts of solar energy is not really 'typical'.

We can certainly custom build an RV based system that will power an A/C with solar, but it's not 'typical'.

Having said that...its getting more and more common in the new off-grid and nomadic trim RVs to see factory installed solar power systems that can run a larger percentage of the on-board systems.

 

[RvNaut]

And an RV with $8,000 to $10,000 worth of added-on lithium batteries, solar panels and associated inverters and other hardware for harvesting and storing large amounts of solar energy is not really 'typical'.

Your money quote is twice my cost....

It is not typical because it isn't simple and people prefer simple... A Class A is not simple, and someone looking to get into one ( or a class C) is taking on more than van or car living, so digging into a integrated solar system is not that much more of a learning curve than learning the furnace, the water heater and the other systems found in more traditonal RVs.

How much Class A experience do you have? Do you live as a nomad?

What is typical for a full time Nomad in a class A? I do not think there is a typical for Class As.

My post is meant to encourage those with some skills to not waste money on BatteryBox systems, but to consider building a solar system that *will* fit their nomad needs.

The electrical needs of living in a Class A can be much more demanding, but it depends on how much juice you need.... IOW if you need to run both your A/C units all the time,, maybe being a nomad isn't for you....

So I refute your claim... for nomads, and in my nomad world, my system is very typical, it is just larger than many have in thier vans.

My system design could easily be downsized to half the cost I subjected myself to.

**************
I also realize and accept that a lot of us do not have $5k to toss into a solar system. Full disclosure... I started with $40k, bought my class A for $26.. ++ taxes, registration insurance, roadside assist, and a crap ton of gasoline to get from Maine to AZ by way of SD and residency costs. .... and over a 14 months was able to eventually buy everything I needed. I now have almost no funds, but am working to rebuild the emergfund. The kicker is I am no longer spending 20% of my SS on gasoline and my payback will be about two years. I *choose* to run a desktop computer(with home stereo) and a large screen, with Starlink and a multicam security system etc etc etc... so I want more power than many.

 

[NctryBen]

good choice just to upgrade to an AGM battery. It is simpler than upgrading the charger unit in your motorhomes converter to one compatible with lithium.

The charger is very easily incorporated… basically unplug old converter and plug in new converter and set to lithium as battery source. And your typical rv has plenty of wasted space to put such a thing as the old converter isn’t always removable without changing out other components. But to run what the op is planning to run $5,000 would be plenty and now with lower cost lithium batteries (I have battle born) that cost can be reduced. I chose the more expensive as I wasn’t as comfortable with the knock offs at the time. Jason is the best example I know of that most RV’s can be converted…
With my four lithium batteries (400ah) I operate water pump, lights, two max air fans and stove vent fan, upright 12v compressor fridge I don’t have to keep perfectly level…, furnace fan, 12v tv with dvd player, trailer tongue jack, all my device charging, macerater pump… plus a 600w inverter charging tool batteries, running coffee grinder and coffee maker, rice cooker amongst other things. I have not gone below 75% unless multiple rainy days. Usually don’t go below 85% on batteries. The panels are overkill so that I can be fully charged even on cloudy days.
My freezer is very cold, only lose things in fridge if it gets unused after time. With AGM batteries you will not usually get the amp hours they advertise. Lithium’s usually exceed… making them easier to size to your system.
I’d need twice the batteries in agm to operate as well as my four lithium… that is a lot of weight. Watch both Hobotech and Will Prouse on their AGM battery testing and recommendations. When you prematurely kill your AGM’s by running them below 50% repeativly… you’ll slap your head like the V8 commercials and say you could have had lithium!
This is my experience and opinion… I’m not an expert… I never was a pert…
What you choose is rarely wrong. Just not always the best. We learn from experience. When we make mistakes we appreciate the upgrades even more. I enjoy not having to hardly think about my electrical needs.

 

[Camper]

I'd go with lithium batteries and not be held back by the old school thoughts. My 100AH lithium's were around $349 each and work perfect every day.

 

[tx2sturgis]

Your money quote is twice my cost....


How much Class A experience do you have? Do you live as a nomad?

I was using your figures above in post #9:

$5000, plus $423, plus $900, plus $3000 in future upgrades if I read it correctly, if not, then let us know.

It is entirely possible to achieve reliable A/C operation with solar panels and large expensive battery banks, but it's not 'typical'...that's all I said. The OP just recently bought a Class A RV and its a 'typical' Class A, without all the stuff you have added. It sounds as if it is more-or-less factory equipped, which is 'typical', in this case meaning 'fairly common'.

And we are not discussing my current situation and past experience, we are contributing to the answers for the OP's question.

But yes, 18 years owning and boondocking in a Class A motorhome. Does that count?

 

[wayne49]

Progressive Dynamics manufactures drop in replacements for older converter-charger units. I replaced an ancient Magna-tek unit that only trickle (3A) charged the batteries, with an intelligent Progressive Dynamics 45A unit that does equalization with the press of a button.

 

[LargeMarge]

...The typical class A uses way more power than can be created via solar and stored in a battery bank. In mine, the biggest energy hog isn't the house sized fridge, it's the 3 rooftop ACs (which are needed to keep the space comfortable)...

.
We! Are! Americans! Or sometimes, we are those pleasant people from Canada!
We can drive Anything! Anytime! Anyplace!
.
We can have a 'typical class A' with not one!, not two!, but three rooftop ACs!
We can discuss our energy hogs as if that is perfectly normal!
.
We can rationalize our decisions using the 'comfortable' defense!
.
.
But some of us learned about reducing our space needs...
...reducing our electricity requirements through reducing our electric appliances...
...reducing our time inside, choosing instead to be outside bonding with the beauty of nature.
And increasing our insulation with smaller windows.
Or using our mobility capacity to go someplace different.
For some of us, our learning came through decades of tragic suffering and loud naughty words.
Some of us carry hideous scarring as a humbling reminder.
.
I think expecting everybody to evolve similarly simultaneously is less than realistic.
Speaking only for one nomad in particular, I think I probably picked the weirdest path for the fun of it.
No other justification could account for this delightful mess.

 

[RvNaut]

$5000, plus $423, plus $900, plus $3000 in future upgrades if I read it correctly, if not, then let us know.

It was $5k all in.

I did not want the OP to get the impression that they should not look to a major conversion.