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7-Year Review: RV Electricity – Solar Power and Lithium Batteries

We didn’t always have an extensive RV solar array. This is our report about frequently making RV electricity with and without solar or lithium batteries while camping for the last seven years. As full-time RVers, we know what works and what doesn’t. I’m sure you know that not everything works all the time.

For the first year, we camped with lead-acid batteries without solar panels. We only recharged our batteries when running our generator or plugged into shore power. Only charging when hooked to a generator makes RV electricity the hard way. We didn’t ruin our batteries or live without electricity. It was a fun but challenging learning experiment. This story will explain how our RV solar and lithium battery upgrade progressed over seven years.

We have seven years of making our own RV electricity.

We are full-time travelers and frequently camp without outside electrical service. Large RVs are not intended for camping outside RV Parks. It has taken multiple years to make enough changes to make our luxury RV electrically independent. You can call this our seven-year progress report. You can expect me to tell both the good and bad about our experiences with solar energy to make electricity for your RV.

Year one

Unlike many RVers who only go from RV park to RV park, we always prefer to camp without being in an RV park. Being in an RV park doesn’t appeal to us. Some call it boondocking; others call it dry camping. We choose to avoid RV parks; instead, we camp in more rustic (wild) settings. We frequently camped and only made RV electricity with our generator to recharge our lead-acid batteries. During this year, we frequently had to run our generator for multiple hours a day, and looking back on it, we frequently failed to charge our batteries completely during the first year. I’m surprised we didn’t kill them.

Stock Photo Lifeline AGM Battery
We had two of these batteries under our steps in our first RV. When they were installed, they were the best batteries you could purchase in 2015. We used and abused them for two years before we sold the RV.

Tortured batteries

Unknowingly, we made RV electricity the hard way, which could have ruined our RV batteries. Frequently undercharged batteries die early deaths. We only ultimately charged our batteries when we went to RV Parks, and we got away with it. Failing to recharge lead-acid batteries fully is a horrible idea. How did we know they were chronically undercharged? We learned later, and in a little bit, I will tell you how we know we tortured our batteries and how you can avoid undercharging your batteries.

Battery Monitor graphic
This is a simplified battery diagram with a shunt. You are guessing the charge level if you don’t have a shunt to measure how much electricity you use. From 2017 to 2018, we didn’t have a shunt, and our batteries were frequently undercharged.

I hope you understand that running your generator to charge lead-acid batteries makes RV electricity the hard way. The key was to run our generator frequently, and since we had lead-acid batteries that resist charging, we frequently only charged them to about 90%. Failing to recharge our lead-acid batteries fully was a colossal mistake, but we got away with it. I will dig deeper into this subject later when I tell you about battery monitoring.

For the second year

In the second year, we added solar to our lead-acid batteries. Could we make our own RV electricity without running our generator? Yes, it worked. During the first two years, we learned a lot about RVing without extensive power. Our RV was pretty energy efficient, and the refrigerator would run on electricity or propane. During our first year without solar power to augment our energy use, we made RV electricity the hard way with our generator and stored it in our lead-acid batteries. We recharged our batteries frequently during the second year, only using our solar panels. Yes, it is possible, but you have to be careful.

Tiffin RV 34TGA Solar Panels 700 watt
Our first RV with solar panels: I installed the solar panels on the wrong side of our RV. They are tilted slightly to allow rain to run off. There was too much clutter on the passenger side of the RV where I should have mounted the panels. Especially in the winter, we discovered that our air conditioner frequently shaded our solar panels. At the time, I went with large (used) panels. It would have been better if I had installed them on the passenger side or installed smaller panels.

Analysis and results after installing solar

We tortured our lead-acid batteries to prove that a functional, effective solar array could charge them. We camped multiple times for weeks without being hooked to the electrical grid. The batteries survived the torture because we carefully monitored them.

solar charge controller battery monitor fuse circuit breaker shutoff switch
Solar charge controller, battery monitor, main solar fuse, and solar charge circuit breaker with the main solar shutoff switch installed on my RV in 2019.

Even after installing solar panels, we continued using our lead-acid batteries, torturing and frequently undercharging them. Perhaps the largest difference during the second year was that we knew we were undercharging the batteries and knew how to charge them properly because we had a battery monitor.

You need a battery monitor.

Every RV rolling off the assembly line should have a battery monitor. The lack of a battery monitor is an example of where RV manufacturers cut corners to increase profits. Without a battery monitor, you are merely guessing about your batteries. Volt meters are not a substitute for a battery monitor. A battery monitor is the most critical component in any RV electrical system. Without one, you don’t know your batteries’ charge level. Here is a link to my article about the battery monitor. A Battery monitor is the most critical part.

Stock Photo Victron Battery Monitor
This is the stock image for my battery monitors. It is too bad they show the voltage on the monitor face. The battery voltage is nearly a worthless number.

During this year, I learned that knowing battery capacity was more important than solar panels and that solar panels are just an alternate charger for your battery. Still, having solar panels enabled us to cut our generator use to almost zero during the summer (assuming we were camping where the temperatures were mild). Here is a link to one of the beautiful places we camped in, West Yellowstone, and never had to run our generator. We were there for two weeks making our own RV electricity. West Yellowstone

Campsite Hebgen Lake West Yellowstone Montana
Campsite Hebgen Lake West Yellowstone, Montana

In 2020, we started over.

In 2020, we changed RVs and started over again.  This year, we got an even bigger RV with much higher power demands. Our new (to us) RV had lead-acid batteries that were woefully inadequate to run our RV when camping without electrical hookups. We knew starting on the first day that our lead-acid batteries would never hold enough electricity to power our luxury RV.

Our campsite at the Meadow Estate Winery, a Harvest Host location.
We frequently dry camp in our RV and make our own electricity using our solar array and battery bank. We never worry about running out of electricity.

The twelve-year-old solar panels didn’t work. They probably never worked and were woefully undersized. Our refrigerator and inverter consumed most of our battery power and discharged the battery in about four hours. Then, we would have to run our generator and recharge. Recharging every four hours was never going to work for us.

2008 Solar
Our RV came from the factory in 2008 with these two solar panels installed. Each, when new, could produce about 80 watts an hour on a typical day. When I replaced them with my solar array, I could frequently make 1350 watts an hour.

In the previous two years, I learned how to operate our RV using our batteries. However, our previous RV didn’t have a residential refrigerator, and our new RV was a power hog. I knew we would have to fix the battery issue, and I had a plan from the beginning.

My RV battery design goals.

I wanted a battery bank with enough capacity to operate for an extended period (at least 24 hours) without recharging and without external power or solar energy. I also wanted to use my air conditioner occasionally without running my generator, using only battery power. We achieved both design goals.

Victron 100/50 Solar Charge Controller and Battery Monitor Screen
Victron 100/50 Solar Charge Controllers fuses and solar shutoff switches installed in my RV electricity charging system in 2020. To the right is my battery monitor display.

We first upgraded our battery system to lithium (before adding solar panels) and measured our actual electrical needs for a whole summer before adding the solar panels. Once I upgraded our batteries to lithium, I could store more power than we would use. My goal was to live normally for at least two days without recharging. Only after knowing whether or not we had enough battery capacity did I add solar panels to help with the recharging.

Our battery box
In 2020, these were our lead-acid batteries. We had four of them. Each pair of batteries could hold 300 amp hours of electricity, and we could use half of the potential energy before damaging the batteries. Combined, these lead-acid batteries weigh 460 pounds.

We could only fix it using lithium batteries.

Our old lead-acid batteries were strong but never able to carry enough electricity to make our RV capable of camping off-grid. The design came from a different era. We wanted at least three times the electricity that these batteries could deliver.

The small parts to make electricity the Hard Way
Parts required to make RV electricity. We are not going to continue producing electricity the hard way forever. It is not that we won’t ever run our generator, but rather, we won’t have to use it nearly as often. You may notice that I purchased the solar charge controllers and all these installation components to install them simultaneously with the batteries—months before the solar panel installation.
Battle Born Battery Bank
Battle Born Battery Bank during installation. Unlike our lead-acid batteries, each battery weighs 30 pounds. Yes, the batteries are laying on their ends, and they have been installed like this for the last four years.

My design estimate is that if we made the electricity with the generator, our battery bank would carry our RV for over two days without recharging. I couldn’t carry enough lead-acid batteries to make my system work. I am glad that my design worked. I aimed to operate our air conditioner for a few hours with only the electricity in our batteries. One winter in Key West, we were the only RV camping without outside electricity, and we had enough battery storage to run our air conditioner overnight without outside electricity. Win!

Our huge battery system

So, in the spring of 2020, we installed a huge lithium battery bank, which provided more than 900 amp hours of usable electricity for our RV. Our huge battery bank did the trick. You can read about it in these posts.

Massive Electric Bucket

Hybrid Mongrel Battery

The battery design proves to be effective

During the winter of our third year, we installed a large solar array with enough capacity to recharge our batteries fully daily, replacing all the electricity we used overnight and living normally. How many solar panels did we need? Rather than guess, we spent an entire month in the summer of 2020 camping without outside electricity and making our own RV electricity with our generator to find that answer. Could we dry camp only using our generator and lithium batteries? We need to know this answer before we design our solar array. The answer is yes, and here is a link to our month-long test results. RV Boondocking Without Solar

Zamp Obsidian Solar
Zamp Obsidian solar panel on my picnic table during the installation. I still believe that this panel is the very best panel for RVs, and the design is perfect. We once had the most extensive Zamp array on any RV. I am sure someone has installed a larger array than I have.

Even though I thought I could fit 24 Zamp Obsidion solar panels on the roof of my RV, I limited the array to 18 panels because I thought 18 panels would carry the load. I still envy the possibility of a 24-panel system, but it rarely would be necessary. Overall, I was correct 18 panels was a good number and not overkill for our RV electrical needs.

Here are a couple of links describing our solar panel installation.

Zamp Obsidian Solar Array

You have too many solar panels on your RV!

Standing on the front of the RV looking at the Phoenix valley. One solar controller is for the panels on the drivers side of the RV and the other controller takes care of the passenger side of the array.
I’m standing on the front of the RV, looking at the Phoenix Valley. These are the best solar panels I could buy. They are made by Zamp in Bend, Oregon. One solar controller is for the panels on the driver’s side of the RV, and the other controller takes care of the passenger side of the array.

Testing our lithium battery system with our solar array

I made the final connections between our lithium battery system and solar array late in the winter of 2020. I started using it for our trip across the southeast, eventually arriving in Key West. Eight months after putting in the battery bank, I finally had a large solar bank to charge the battery. In 2021, we crossed Texas, still in the winter, and then spent the summer in Tennessee, Virginia, and North Carolina before turning south to Key West in Florida. Here is a link to how our RV solar array and lithium batteries worked during an extended camping stay, making our own RV electricity in the Smokey Mountains. Extended RV Dry Camping — twelve days on solar

Our RV in site 6 at Linville Falls Campground
Our RV in the Smokey Mountains on a rainy day. In this 2022 photo, half of our solar array can be seen. I never expected it, but we can produce lots of electricity even on overcast days.

Could we operate our RV air conditioning using only our battery bank?

The answer is yes, and we proved it repeatedly while we were in Key West for the winter of 2021-2022. Even in the winter, Key West was still hot (and muggy). I already knew from previous tests that the solar array could not make enough RV electricity to keep up with the electricity consumption of the air conditioner. But the battery bank was ample to power our air conditioner while sleeping. The solar array went a long way toward replacing all the electricity consumed overnight. Here is a link to the analysis. How did we live on Solar when at Key West?

Our campsite at Key West
Our campsite at Key West wasn’t perfect for making solar power, but sometimes you have to go for the view instead.

What we learned during the last seven years about making your own RV electricity

We didn’t know if our batteries were the correct size or if our solar array was adequate until winter 2021. The result is that we had an amply-sized RV electrical system. Even if I had put 24 solar panels on my roof, I still would have to occasionally run my generator (making RV electricity the hard way) to recharge my batteries.

Our RV at Manatee Springs and our new Hurricane Prima Kayaks
Our RV solar array. Looking at this photo, I can tell that I could have installed 24 solar panels, but the walking room would have been extremely limited. If I had more panels I could run my air conditioner and charge my batteries at the same time.

The first takeaway is that in anything you do with lead-acid batteries, you are making electricity the hard way. Second, it is even more challenging if you are trying to charge your lead-acid batteries with only solar. Lead-acid batteries resist charging, and the closer they are to full, the more they resist. This is RV electricity the hard way. Even if you have a huge solar array, if you are trying to charge lead-acid batteries, you will be wasting most of the energy that hits the panels. This is RV electricity the hard way.

How to make RV electricity is the easiest way.

So, what is RV electricity the easy way? Combine a big battery bank with an ample solar array, and you will make electricity as easy as possible. If (it proved true) we could camp for more than 24 hours only using the electricity in our batteries, then we sized the battery bank correctly for this sizing intent. If we could also use our air conditioner operating from our batteries for an extended period, this would prove our battery bank was sized for full-time RVing.

Too many solar panels! Picture is still one short of the full array.
All my panels are tilted toward the sun. We only do this when cleaning under them, as we travel frequently and tilting is not automatic.

How has the RV electrical system held up over the years?

Since we installed the batteries and solar charge controllers, we have had two problems in the last three years: Both issues were electric, and we found the first one before we installed the solar panels. The other thing to know is that the first problem was 100% my fault. I will cover the second problem, a faulty circuit breaker, in a minute.

The main battery disconnect switch

I failed to tighten the positive 4-0 cable on my main battery disconnect switch sufficiently. After bouncing down the road hundreds of miles later, the connection loosened. Since we were running our air conditioner from our battery bank (large load), the resistance caused by the loose connection created enough heat to destroy the disconnect switch.

Battery Monitor Shunt, Fuse and Main Battery on/off switch
Battery Monitor Shunt, Main Battery Fuse, and Main Battery Disconnect Switch. The large wires with red ends on the terminal connect the positive side of the battery to this disconnect switch. This switch failed because the cables on the back were insufficiently tightened. When repaired, double nuts with nylon lock nuts and the correct torque will prevent it from happening again.

The solar panel circuit breakers

One of my two solar panel circuit breakers occasionally shuts off solar charging without notice. After troubleshooting, I found that this circuit breaker probably had an internal failure and didn’t like vibrations while we were driving.

Solar Driver's & Passenger Circuit Breakers
Solar Drivers & Passenger Circuit Breakers. Pushing the red button opens the yellow lever, disconnecting the solar panel and shutting off charging from half of my solar array. The driver’s side circuit breaker disconnected even though the solar panels were not putting out too many amps—only when we were driving due to vibrations.

RV electricity Q&A

We have the answers if you have questions about RV solar, batteries, or RV electrical systems. The “Our RV Solar Series” has more than 22 articles on RV solar, covering nearly every aspect of RV solar. If you have any questions about any of the articles, let me know, and I will gladly answer them personally or add them to the series.

Can One Lithium Battery Replace Four Lead-Acid Batteries?
When we switched to a lithium-only RV electricity system, this one lithium battery replaced my RV’s four lead-acid batteries. The four lead-acid batteries still work (I gave them to a friend), but this change saved me almost 500 pounds of extra weight.

How can one lithium battery do the job of four lead-acid batteries?

My RV electricity system is designed around my RV, and the easiest way for me to change the electrical system was to keep the alternating current part of my RV electricity separate from the direct current part of my electrical system. I describe the system in these two articles:

Hybrid Mongrel Battery

Can one lithium battery replace four lead-acid batteries?

My DC to DC converter is mounted on the roof next to my inverter. The input wires are connected to my main battery and the output wires are connected to my solo battery.
My DC-to-DC converter is mounted on the roof next to my inverter. The input wires are connected to my main battery, and the output wires are connected to my Lion battery. This device allows me to charge my Lion battery independently of my other batteries. Even if I have exhausted my big battery bank, my solo battery still has a full charge and is ready to start my generator.

Critical things to understand about your lithium batteries

I frequently see questions from people who do not understand RV electricity and lithium batteries. Even today, most people don’t understand the differences between lead-acid and lithium batteries, so I wrote this article discussing lithium battery myths.

Ten Lithium Battery Myths and Answers

How do you know when you are doing a good job both designing and using your system?

The answer is simple: we measured power in and out several times daily. Here is a link to our measuring tool. Battery Monitor

Please subscribe and join us on our journey.

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As you know, our blog income is zero, which allows us to be independent and tell the truth. We do not get income or commissions. No, we don’t make paid endorsements. We don’t make recommendations; instead, we will tell you what we like (or dislike). The links are only provided as a quick reference to help our readers.

Lion Energy UT1300 Lithium Iron Phosphate Batteries

Battle Born BB10012 Lithium Iron Phosphate Batteries

Magnum 2812 Inverter Converter (charger measured at 125 amps per hour)

Victron 712 Battery Monitor

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9 thoughts on “7-Year Review: RV Electricity – Solar Power and Lithium Batteries”

  1. Brenda G Taylor

    I sure look forward to your post every week. I feel like it’s my knowledge lesson for the week. you’re just amazing and I thank you that I’m included to learn about it.

  2. Excellent article! ln “RV Electricity the Hard Way, without solar or lithium” you mentioned that before having solar or lithium you charged with a charger when on generator or shore power. Did you use a special charger or just a smart converter normally on RV’s?

    1. Just the inverter/converter built into the RV. On my previous RV, it was painfully slow. I was very happy with the charge rate of our Magnum inverter/converter which occasionally hit 110 amps per hour.

      The biggest problem that most people face and then fail is they don’t complete the float cycle on lead acid batteries. Most believe that float indicates that they are full. Nothing could be further from the truth. When they finish the float cycle then they are full. The float cycle starts at about 90% and then takes as much time as the bulk and absorb cycles combined.

  3. Hi! Hey are you still using your lion batteries or have you completely gone to Battleborn. I went back through your posts but am still unclear what you battery bank is currently made of? 900 amp hours of battle born or is there more? Just trying to catch up.

    I ended up with 900 amp hours of battle born batteries in mine and a year ago my last upgrade was replacing and upgrading my inverter to a much more robust designed Gandel 4000 watt inverter. Its uses DC to DC conversion before changing the power to pure sine wave which made it much more compact with much lower stand by power consumption.

    I even have pictures of me showing that charging my Tesla from my RV solar and battery array is actually rather easy.

    1. I have eight Battleborn batteries (800 amps) dedicated to the Alternating Current side of the system and one Lion Energy (100 amps) battery running the DC system.

      The Lion Energy battery gets power from either the engine or the DC-to-DC charger and is full 99% of the time. It also acts as a backup battery in reserve so that I can start the generator if (as has happened) I completely deplete the big battery bank.

  4. Good Article, Scott – my 2008 Allegro Bus 42QRP is also an energy hog.

    We have 1600W of solar and 800Ah of Lithium, but I still struggle to run the A/C unit for more than a few hours. The Residential Refrigerator is a large power hog.

    Plus, there are other phantom loads that combined can be significant. With the advances and decreasing prices of Lithium Batteries, I wish I would have gone different with my Lithium set-up, but it was the best at that time.

    1. I hear you, Nick; teaching a luxury RV how to be a camper isn’t an easy process. One of the phantom loads is the inverter, which converts DC to AC, which alone can consume 20% of your battery power. No free lunch is a true statement in RV electricity.

  5. Thanks for sharing. Sounds like some very interesting problems with some excellent solutions. Keep up the good work & HAVE FUN.

  6. Scott, this was clearly a long and trying project. The subject-matter involved applying a very complex, difficult, leading edge technology, science, engineering and the peculiar context of RV living. You deserve recognition for the patience, persistence, and methodical approach that characterizes your efforts. Well done! There are a lot of us out here that will benefit from the wealth of information your articles provide.

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