What size solar panel do I need to run a 12v fridge?

A lot of people truly enjoy living their everyday lives on their own RVs. New places, new people, new experiences, who don’t want that! However, while there are a lot of good things about living in the RV, there’s also a lot of challenges, just like the money you have to spend in powering up your van!

While gas-powered generators and inverters are the most popular way on how you can power up your mobile home, there’s actually a cheaper alternative: the use of solar panels!

We know what you’re thinking: it’s too expensive to install! While it is true that solar panel installation could be more expensive than filling up your gas-powered generator or installing an inverter for your RV battery, the amount you will save once the solar panel is already installed is unbeatable! Not only that, those people thinking that solar panel installation in RV can get expensive doesn’t realize that you would need smaller solar panels for your RV since you have less appliance compared to a regular home.

We’ve come up with the basic information on how you can use a solar panel to power up your appliance inside your RV. It includes the simplest yet the most important information such as the solar panel size you would need to run certain appliances such as your 12v fridge.

Basic Information About Solar Panels

Just like what we all know, the size of the solar panel fully depends on the appliance that you’re thinking of powering up. Here are some questions you have to answer when powering up some of your appliance inside your RV:

  1. What appliance would be connected to the solar panel?
  2. How many appliances?
  3. How many voltages do these appliances need?
  4. Would they be used every day or only on when needed?
  5. How many hours are they expected to run in a day?
  6. If solar panels are unavailable, say on the occasion of bad weather, should they be connected to an alternative power source?
solar panel on a rv roof

Pretty meticulous, right? Well, the truth is, when talking about a power source for your appliance in your RV, especially that of an alternative one, you should really be detailed-oriented. Not only would it allow you to make the most out of your solar panels, but most importantly, bear in mind that people living in RVs don’t have the reliable maintenance and troubleshooting services that power source companies give to regular homeowners. You wouldn’t want to do regular repair and troubleshooting tasks for your RV power source, right? And surely, you wouldn’t want to damage your expensive appliance. This is why you really need to determine the answers to these questions before proceeding with the installation of your solar panels.

Powering Up a 12v Fridge

12v fridge in a van

We would take a 12v fridge as an example of an appliance that you would be powering up through solar panels. Why a 12v fridge? First and foremost, 12v is the most common voltage of RV appliances since they could easily be powered up with a gas-powered generator or an inverter connected to your RV battery. It’s also the best pick when you’re thinking of using solar panels. On the other hand, a refrigerator is probably the most sensitive appliance even in regular households. Not only should it be continuously hooked up to a power supply, but one power surge or fluctuation could already damage a fridge. Aside from that, you would have to connect it to a reliable power source, or else you’re at risk of spoiling all of your food supply!

In short, if you have succeeded in powering up your fridge through a solar panel, then powering up other appliances would be a breeze for you!

In order to correctly and efficiently connect your 12v fridge to a solar panel source, you should determine the average power that your fridge could consume. This is important since you will be setting up the configuration of your battery which will be connected to your solar panel. According to an article from Sciencing, it is best to follow this computation method to get the most accurate power consumption of your fridge. If a fridge may read 115 volts and 4.5 amps of current, you have to multiply these two quantities to calculate its power demand: 115 x 4.5 = 517.5 watts of power.

Minimum Requirement for a Solar Panel

solar panel

For a 12v fridge that is expected to run for 24 hours, the minimum solar panel requirement is that of a 100 watts with the dimension of 42.2 x 19.6 x 1.38 inches. You may want to check the product description of your solar panel and see if it meets the minimum requirement for running a 12v fridge. Below are the most important specifications of a solar panel, but for a complete and more detailed list, you may want to check out Invensun’s article about 100 watts solar panels.

            100 watts solar panel minimum requirement for a 12v fridge:

Standard Power: 100wp

Tolerance: 0-+3%

Short Circuit Current (ISC): 5.86A

Open Circuit Voltage (Voc): 22.1V

Maximum Power Current (Imp): 5.52A

Maximum Power Voltage (Vmp): 18.1V

Maximum System Voltage: 1000v

Number of Cells: 36 pcs

Maximum Fuse: 15A

Since it is the minimum requirement, in order to properly power up your 12v fridge with a 100 watts solar panel, you’re expected to have a new 12v battery that is free from any defect or damage. With this, you can be sure that no amount of energy is lost during the transfer of power from your solar panel to the battery since you’re only power from a 100 watts solar panel. Aside from that, you’re expected to expose your solar panel to direct sunlight for long hours. Let us say that a 12v fridge and 100Ah is 12×100  equals to 100 watts-per-hour or 1.2 kilowatts per hour. In short, you should expose your solar panel to direct sunlight for a minimum of 4 hours in order to generate 740 watts needed for a 12v fridge that mostly runs on 1.2kWh a day. You should repeat this every day, almost every afternoon, in order to enjoy the benefits of your 12v fridge in your RV without the worry that your fridge may run out of power anytime!

On the other hand, if you know for yourself that the weather around your area is unforgivable, you could still stick with your 100 watts solar panel. However, you should invest more on your battery and opt to but a new 24v or 48v units.

Why would you need a 24v or 48v battery for a 12v fridge? Since you’re in the middle of unforgivable weather, you’re expected to make the most out of any sunny afternoon and stock up as much power as you can in your battery from your solar panel. Say that a 12v battery is good for an entire day of refrigerator use, then a 24v can go up to 2 days of use and a 48v could fo up to 3! In an article from Rainbow Power Company, they have listed down the differences among 12v, 24v, and 48v solar panel batteries. From their basic features all the way to their detailed specifications.

In this youtube video from GreatScott!

He showed a comparison between a store-bought and a DIY solar panel. So if you’re of further increasing your savings through the use of solar panels, why not create one on your own?

See? Using a solar panel for your 12v fridge isn’t that hard right? Just bear in mind that aside from the quality and specifications of your solar panel, you should also invest in scoring a good and high-power battery. Not only because it’s the one to store up your power, but most importantly, it is your battery that will be directly plugged into your 12v fridge.

So what are you waiting for? Lessen your use of your gas-powered generator and RV batteries and save more money with the use of solar panels! Maybe we have forgotten to mention it… but it could save Mother Earth, too!

Hivan Team

As an independent team of travelers, we do share positive and negative observations as we find them and make our best to help and inform other vanlifers around the globe.

Recent Content