What Size Solar Panel to Charge 120Ah Battery

What Size Solar Panel to Charge 120Ah Battery

The many benefits of solar power have attracted not just homeowners but also outdoor junkies as well. This is especially useful for those travelling in an RV. Pair a good battery pack with a set of RV solar panels and you're all set to travel just about anywhere without worrying about losing power.

If you're also looking to try the famous battery and solar panel setup, one of the first things you have to do is to size up both your power pack and panels. A lot of campers go for a standard 100Ah lithium battery, but if you want a little extra output, a 120Ah battery is also a good option.

Now the question would be, what size of solar panels should you pair it with? You'd have to do a bit of math for this but don't worry, it's very simple to calculate a rough estimate of how much power you need for your panels.

The general rule would be to make use of this formula:

Amp hours/peak sun hours = amps

Amps x battery voltage = your solar panel's size

For instance, if you have a 12V 120Ah battery and about 5 hours of peak sun hours in your camping location, the computation would go like this:

120Ah / 5 peak sun hours = 24 amps

24 amps x 12V = 288W

All in all, you'd need around 300W of solar panels for pairing with your 120Ah battery. It's up to you whether you want to break this up into three 100W solar panels, two 150 solar panels, or just one big 300W solar panel as long as everything fits in your RV space.

What Other Factors Should Be Considered When Sizing Your Solar Panels?

It's good to know that there are other factors to consider when sizing solar panels for your 120Ah battery. One would be your battery type. Lithium batteries especially LiFePO4 batteries are superior in terms of overall quality. However, you might need bigger solar panels for this as they sometimes require more output than lead-acid batteries.

Another thing to consider is your solar charge controller as this will have a big impact on your charging efficiency. This could either be a Maximum Power Point Tracker (MPPT) solar charge controller or a Pulse Width Modulation (PWM) regulator. An MPPT solar charge controller is generally the more efficient choice, but it would still boil down to what kind of setup you have so make sure you do your research too.

If you want a more accurate computation of what size solar panels you need to charge a 120Ah battery with all these factors included, you can also make use of available solar panel size calculators online. These are convenientjust input the details of your battery and panels to get a good idea of the size you should get.

What Is the Best Battery For Solar Charging?

Solar charging requires a solar battery with good storage capabilities. Your best pick for this would definitely be a lithium iron phosphate battery (LiFePO4). These have an

impressive capacity and are backed with innovative features as well, such as a built-in battery management system. This BMS makes sure every cell inside the battery is optimised for smooth performance and also provides automatic protection against common battery issues.

Best of all, these power packs are considered lithium deep cycle batteries too. This means your battery pack can be safely discharged down to 80% instead of the usual 50% so you can enjoy a longer runtime. It's even more important for off grid campers who rely on solar energy for power during the evening to power their essential appliances.

Level up your next camping or road trip experience now! You already know how to size up your panels properly so it's time to go shopping for those portable power sources. Check out our solar panel and battery range at Outbax today for amazing finds at equally excellent prices.

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