Our Favorite 12 Volt Solar Battery Chargers in 2021. Great for Off Grid RV Camping
The high mountain peaks covering the horizon, the hoot owl sounds coming from the forest, the smell of wild flowers on the warm evening wind.
The roar of a noisy and foul-smelling generator that can be heard a mile around, the harmful fumes that make you feel like you’re camping in the middle of a traffic jam.
Which one of these scenarios doesn’t belong on your RV camping trip?
Yes, we thought so too 🙂
If you want to finally free yourself from the noisy campgrounds, hookups and the ever-present hum of generators, while still being powered up and enjoying your RV adventure, then you should really consider investing in a solar charger kit.
Many RV owners are trading their noisy generators for solar battery chargers. A solar system is silent, has no moving parts, produces no harmful emissions and requires very little maintenance. Instead of loading up on generator fuel, all you would have to do is face the solar panels towards the sun and enjoy free renewable energy.
What used to be a big financial investment with a long return on investment of up to 10 years or more, has developed into a booming industry where everyone can afford solar panels of all kinds of sizes that can be easily installed and used without the need of a “professional installer.”
In this article we will give you a brief description of what we consider to be the best 12 volt solar powered battery chargers for RVs available on the market right now. We have also included a buyer’s guide at the end of the article where you’ll find everything you need to know about choosing the best solar battery charger, so make sure to check that out as well.
DISCLAIMER: Greentumble is NOT receiving any payment from the companies listed in this review article.
Why is Renogy our favorite for 12 volt solar battery chargers?
Renogy holds the first spot on our list of the best 12 volt solar battery chargers for RV camping in 2021 simply because it offers a remarkable combination of manufacturing quality, latest solar technology, power reliability, and… affordability!
Yes, Renogy has the best price for solar chargers at the moment. Sorry competitors, but that’s the truth!
The advanced technology and the company’s efforts to constantly improve their products puts Renogy on the cutting edge of RV solar gear. We were really impressed especially with the performance of the Renogy 200W Suitcase Kit and considered that the investment was well worth it for the massive solar output performance this solar charger kit provides.
All Renogy solar charger systems utilize top-of-the-line solar panels for maximum light absorption, while minimizing power drop caused by cloud cover or shaded areas. You can really see the manufacturing quality when you handle these panels closely.
According to Renogy, their solar modules can withstand high winds (up to 2,400 Pa) and snow loads (up to 5,400 Pa). We didn’t run any tests in such conditions yet, so if you did… leave a comment below and tell us the results.
The panels themselves are fixed in a corrosion-resistant aluminum frame making them very lightweight and easy to move around. They can be mounted and secured on the roof of your RV as they come with pre-drilled holes on the back of the panels, or they can be mounted on the ground.
What we really like about Renogy’s solar battery charger kits is the wide range of panel wattage choices and the hundreds of positive reviews they got on Amazon just confirms how reliable their solar systems are.
Renogy 50 Watt Monocrystalline Solar Kit With Charge Controller
The Renogy 50W Solar Kit is the smallest wattage system we recommend for 12 volt battery charging. Anything less than 50W will make you frustrated. The charging speed depends a lot on the number of solar cells a panel has. The more solar cells, the more solar energy can be absorbed and converted into electricity in a given moment.
- Best suited for small power consumers.
- Compatible with 12V deep cycle battery types: sealed, gel and flooded.
- Ideal battery capacity for the Renogy 50W Kit: 12V battery bank rated up to 70 amp hours.
Small power consumers lifestyle
Here a rough breakdown of the amp hours used by the small power consumers in an average day:
– one overhead light for three hours (6 Ah)
– water pump running for 40 minutes (8 Ah)
– charging a phone for two hours (4 Ah)
– charging a laptop for one hour (5 Ah)
– other miscellaneous items such as clock, carbon monoxide detector, etc. (2 Ah)
Total consumption: 25 Ah
Charge Controller
The 50W RV solar kit comes with the 10A PWM charge controller (manual book). This high-tech device features advanced digital technology, it’s very easy to setup and it protects the battery bank from discharging or over-charging. And on top of all this, it operates fully automatically and it allows you expand your system up to a maximum of 120W.
Charging speed test results:
Our testing method was very simple. We connected the 50W solar charger kit with a half drained 12 volt battery rated at 50 amp hours and measured the time it needed to charge the battery to full.
The Renogy 50W solar panel fully charged our battery from 50 percent in about 6.5 hours of direct sunlight (quite slow) and 9.5 hours in partially cloudy conditions. Its small size is the main drawback regarding the charging speed, but that’s normal because it has a much smaller surface area covered with solar cells when compared with a 100W panel for example.
Best Starter Kit: Renogy 100 Watt Monocrystalline Solar Kit With Charge Controller
The Renogy 100W Solar Starter Kit is perfect for people looking to start their solar lifestyle. This system is great for any off-grid uses, such as small cabins, RVs, sheds, and boats. The kit has everything you need to get started.
The portable version of the Renogy 100W is a perfect option if you don’t want to mount panels on your RV or camper. Setting up a portable system to charge your battery bank takes just a couple of minutes. It comes with adjustable legs and the panels fold up together for easy mobility.
- Best suited for conscious power consumers.
- Compatible with 12V deep cycle battery types: sealed, gel and flooded.
- Ideal battery capacity for the Renogy 100W Kit: 12V battery bank rated up to 100 amp hours.
Conscious power consumers lifestyle
Here a rough breakdown of the amp hours used by the conscious power consumers in an average day:
– one overhead light for six hours (12 Ah)
– water pump running for one hour (12 Ah)
– charging a phone for two hours (4 Ah)
– charging a laptop for two hours (10 Ah)
– running a vent fan for five hours (10 Ah)
– watching a 12-inch TV for one hour or using a stereo for two hours (4 Ah)
– other miscellaneous items such as clock, carbon monoxide detector, etc. (2 Ah)
Total consumption: 54 Ah
Charge Controller
The 100W standard solar kit comes with the 30A Wanderer charge controller and the portable kit comes with the 30A Adventurer charge controller. Both of these RV solar charge controllers allow you to expand your solar system up to a maximum of 400W.
If you decide to go with the 100W or 200W standard solar kit, we highly recommend you get some of these adjustable solar panel roof tilt mounts for the panels as this will allow you to change the angle of the panels for maximum power output. Most people tend to ignore this factor, but here’s why it’s important to be able to tilt your RV solar panels:
Tilting = More solar power! This is the main reason you should tilt your solar panels. With a proper tilting kit such as this one, you can boost your solar power output up to 20 percent more in sunny days and up to 40 percent during the winter months or partially cloudy days.
Extreme temperatures affect solar output. Tilting allows the air to move around the panels and this will keep them cooler when the sun is too strong. Keeping panel temperature as close as possible to 77 degrees Fahrenheit (that’s 25 degrees Celsius) will significantly improve your solar panel’s output efficiency.
Charging speed test results:
It took around 3.5 hours (in direct sun) to fully charge a 12 volt battery rated at 50Ah from 50 percent charge and a bit more than 6 hours in partially cloudy weather. It’s a significant difference from the 50W solar panel. With the 100W solar kit you really start to feel the real potential of solar energy.
Renogy 200 Watt Monocrystalline Solar Kit With Charge Controller
UPDATE!
After owning two portable solar systems 2 x 200W for almost six months now, we just wanted to give an update. We still use it and absolutely love it. The panels are collecting sunlight on a daily basis and so far we had no performance issues. We also learned how to be more energy efficient and we are happy with how it works out for us. It always takes one or two months with a new system to get used it and learn how to handle it, but this is the case for almost anything new you purchase in your life (like buying a new car). The only issue we have had was one of the supporting legs broke (they are not that sturdy) so we had to repair it at a local shop. This was a simple $10 fix.
We just recently upgraded our 200W portable system by adding an extra 200W portable system and upgraded our battery bank capacity to 400 amp hours. The result? AMAZING! There is a lot of solar flowing through our battery bank now, but we spend a lot of time in our RV so we need it.
- Best suited for average power consumers.
- Compatible with 12V deep cycle battery types: sealed, gel and flooded.
- Ideal battery capacity for the Renogy 200W Kit: 12V battery bank rated up to 200 amp hours.
Average power consumers lifestyle
Here a rough breakdown of the amp hours used by the average power consumers in an average day:
– running lights for 10 hours (20Ah)
– running a water pump for an hour (12 Ah)
– watching a large TV for two hours (12 Ah)
– using a microwave for 30 minutes (40 Ah)
– using a laptop plugged in for four hours (24 Ah)
– running a vent fan for eight hours (16 Ah)
– other miscellaneous items such as clock, carbon monoxide detector, etc. (2 Ah)
Total consumption: 126 Ah
Charge Controller
The 200W standard solar kit comes with the 30A Wanderer charge controller and the portable kit comes with the 30A Adventurer charge controller. Both controllers allow you to expand your solar system up to a maximum of 400W.
Charging speed test results:
We’re pretty impressed with the performance of the 200W solar kit. In just 2 hours of direct sunlight our 50Ah battery (12 volt) recharged from 50 percent to 100 percent without any interruption.
A significant improvement we noticed at the 200W solar module is the performance in cloudy conditions. It took about 4 hours in partially cloudy conditions for the 200W panels to fully recharge a half drained battery. It’s obvious that they are much more effective at absorbing sunlight than the 50W or 100W panels as they have more solar cells.
Renogy 400 Watt Monocrystalline Solar Kit With Charge Controller
- Best suited for above average power consumers.
- Compatible with 12V deep cycle battery types: sealed, gel and flooded.
- Ideal battery capacity for the Renogy 200W Kit: 12V battery bank rated up to 200 amp hours.
Charge Controller
This 400W solar kit comes with the 30A Wanderer charge controller and you cannot expand your wattage size in this case, as the charge controller can support up to a maximum of 400W.
Charging speed:
This is the ultimate charging solar kit for RV’ers. This kit can fully charge a 200 amp hour battery bank from 50 percent in about 3 hours under direct sun. The panels will take some space, but they won’t let you down when it comes to power output.
The fundamentals of a basic 12 volt solar charger rig
It’s not rocket science – A basic solar charger system consists of one or more solar panels connected to a charge controller, which in turn is connected to a battery bank and a 12 volt outlet.
The solar panels are made up of photovoltaic cells that absorb and convert the sun’s energy into electricity. You can read more about solar panel types and efficiency ratings in our article What are the most efficient solar panels on the market?
The charge controller’s sits between the battery and the solar panel and its main purpose is to prevent the solar panels from overcharging the batteries. It also regulates the charge flowing from the panels to the battery bank in order to increase battery longevity.
A charge controller is rated in amps and you can expand your solar system according to how many amps the charger can support.
Portable versus fixed solar kits: Pros and Cons
The portability of a solar system is very beneficial and it’s our favorite option. With a portable system you can charge your RVs battery bank while you’re parked in the shade and you can carry your portable system anywhere you want, be it around the house or at your off-grid cabin. Another important advantage is the super easy setup. All you need to do is set the panels up and plug them. Done!
In our case, we prefer the portable version because it allows us to use the solar kit even when we are not using the RV, so if you’re looking to have free mobile power anywhere you go, we recommend the portable systems.
On the other hand a standard fixed solar kit can charge your battery bank continuously while in the sun. You just install it one time and you don’t have to worry about it anymore. You can produce electricity even driving down the road, something you cannot really do with a portable system.
If you decide to go with the 100W or 200W standard solar kit, we highly recommend you get some of these adjustable solar panel roof tilt mounts for the panels as this will allow you to change the angle of the panels for maximum power output. Most people tend to ignore this factor, but here’s why it’s important to be able to tilt your RV solar panels:
Tilting = More solar power!
This is the main reason you should tilt your solar panels. With a proper tilting kit such as this one, you can boost your solar power output up to 20 percent more in sunny days and up to 40 percent during the winter months or partially cloudy days.
Extreme temperatures affect solar output.
Tilting allows the air to move around the panels and this will keep them cooler when the sun is too strong. Keeping panel temperature as close as possible to 77 degrees Fahrenheit (that’s 25 degrees Celsius) will significantly improve your solar panel’s output efficiency.
Another important thing to consider is that fixed solar kit can give you the most for your money as it’s much cheaper than a portable system of the same size.
How much solar power do you need for your RV?
Simply put, your RV lifestyle is the main factor that comes into play when it comes to how much solar capacity you need. You might get by on living with just a trickle of electricity, or you might use as much electricity as you do at home. It all depends on how many electronics devices you are using.
To find out which solar battery charger is ideal for your lifestyle, first invest some time into finding out how much energy you use on an average day. Also, by learning how much energy usage you can control by adjusting your consumption patterns will most likely save you a lot of money on your solar battery charger kit.
Calculate Your Daily Power Consumption
Here’s what you need to do in order to estimate your daily average amp-hour power requirements of your RV:
Step 1. Find out the amp-hour rating of your RV battery bank.
Step 2. Set on a boondocking trip without using a generator or any other power source. Go only with your fully charged battery bank. Also, (important!) make sure you have a multimeter with you.
What you need to do is find out how long does it take for the batteries to be half drained when powering your RV under normal usage conditions.
Step 3. Check the voltage of your battery bank with the multimeter (directly at the battery bank is more accurate) before using it. It should indicate a voltage of 12.60+ for a 100% charge. Use this chart to see the charging state percentage that corresponds with the measured voltage.
Step 4. Use your RVs 12-volt battery system as you normally would on a camping trip. After 24 hours, check your battery voltage. If you have more than 50 percent battery, use it one more day.
Step 5. After another 24 hours, check your battery voltage again. If the batteries have enough capacity left for another day, go for it.
When your battery bank capacity reached 50 percent, it’s time to do some simple math calculations.
Step 6. Let’s assume you have two group 27 deep-cycle batteries, with a 90 amp-hour rating each (180 amp-hour in total), that were fully charged before setting on the trip.
By dividing the battery bank’s rated amp-hour capacity by 2 (since you used only 50 percent of the battery capacity) you will find out how many amp-hours you consumed over your test period. In this case you used (180 / 2) a total of 90 amp-hours.
If it takes around three days for the batteries to get down to 50 percent charge, you can finally determine your power usage in one day by dividing 90 (total amp-hours used) by 3 (number of days) giving you 30 amp-hours used each day of your test period.
Now that you have a good estimate on your daily power consumption, it’s time to figure out how much solar is required to replace those 30 amp-hours consumed on an average day. During summer and spring you will most likely be exposed to around 5 peak sun hours daily (on average).
A 100 watt solar panel is capable of producing between 5 and 6 amps per peak sun hour. That’s approximately 30 amp-hours per day. In the above scenario, where the daily power consumption is 30 amp-hours, it may seem that a single 100 watt panel would be just perfect. Well, not really.
We all know the sun doesn’t always shine (even in Arizona). If you find yourself in days with significant cloud coverage, your 100 watt solar charger isn’t going to produce 30 amp-hours of electricity. So having an excess of solar capacity is always a good thing.
Our advice is to go with a 200 watts portable system even if your amp-hour consumption is less than what the solar panels can normally produce during peak sun hours. This way you won’t have to worry about the cloudy and rainy days.
Seven reasons why you should go solar right now
Free fuel: Once you got yourself a solar system, you’ll enjoy unlimited free and clean fuel to power up your mobile lifestyle.
Easy and safe to install: You don’t have to call a professional installer to get your solar charger system installed. The solar kits come with everything you need in order to set up the system yourself in just few easy steps.
Best for your batteries: The most effective way to charge your power bank is slowly and steadily, and that’s exactly what solar chargers do.
Protect the environment: Solar is a great way to reduce your carbon footprint. It doesn’t release harmful emissions into the atmosphere when operating.
More neighbor friendly: Your neighbors (especially the forest inhabitants) will love you for not disturbing them with a noisy generator 🙂
No maintenance: Except for cleaning dust from the panels from time to time and making sure the wires are properly connected, there’s nothing else to worry about.
Access energy anywhere under the sun: You don’t have to worry about keeping your RV powered up when you’re off-the-grid. Just place the solar panels under the sun and instantly you’ll be able to generate electricity.
