Embark on a road trip with confidence, knowing you have a 3-way RV fridge or 12V compressor fridge that can run off battery power while driving—as long as your battery has enough capacity to meet the energy needs.
Dive into our blog to learn more details about different RV fridge types, identify their energy consumption, and discover effective ways to run your RV fridge on a battery efficiently without draining the battery.
Let's get started!
Different Types of RV Fridges
Depending on the type of RV, motorhome, or van you own, you might have one of the following types of refrigerators:
1. 3-Way Fridges and 2-Way Fridges
Many older RVs and small campers typically come equipped with 3-way refrigerators that can operate while you're driving.
The 3-way refrigerator can run using propane, 120V AC, or 12V DC power sources. It can be set to run on an RV battery while driving, which is often referred to as the "third way." However, this 3-way fridge can quickly drain your RV battery if you forget to switch it off DC once you park.
In comparison, 2-way refrigerators are commonly used in more recent RV models. They’re larger than 3-way fridges and are often found in larger Class B, smaller Class C motorhomes, and many fifth-wheel trailers. The 2-way fridges can only run on propane and 120V AC when plugged into shore power at a campground.
2. Compressor Refrigerators
Compressor refrigerators for RVs work similarly to the ones you have at home, using a compressor to cool the fridge and keep food cold. They're efficient on both 12V DC and 120V AC power, making them suitable for use while driving or when connected to shore power.
Can greatly adjust to various temperatures, climates, and conditions, providing you with a reliable refrigeration solution if you’re seeking the comforts of home on the road.
Cool down faster and maintain a more consistent cold temperature compared to other types of RV fridges. If you exclusively camp with full hookups, you will probably prefer these residential-style refrigerators.
More expensive than other types of RV fridges.
Must be constantly connected to power to run.
Models that run on 120V AC will require an inverter, which can drain your battery faster without a reliable charging system.
12V RV Refrigerators
While RV compressor refrigerators that run on 120V AC power cannot run directly off the battery while driving, newer 12V refrigerators—types of compressor fridges—are now being increasingly used in RVs. These 12V portable refrigerators can run on 12V DC power, allowing them to be powered by the vehicle's battery when you're on the move.
The 12V RV refrigerator is quite energy-efficient, and it can run off your battery while driving without significantly draining the battery. For instance, BougeRV offers 12V fridges in various sizes with ECO mode that can keep your food cold without depleting your car's battery. Additionally, 12V fridges are lightweight and relatively easy to install.
One potential drawback of 12V RV refrigerators is that, in extremely hot weather, some models may struggle to maintain sufficiently cold temperatures for your food and beverages. Furthermore, they are generally smaller in size, which may limit the amount of food and drinks you can store.
3. Absorption Fridges
Absorption fridges, also known as gas-electric fridges or propane fridges, have been the traditional option and the RV standard for many years. They can run on 120V AC power, 12V DC power, or propane (LP gas). This versatility means you can operate an absorption fridge on either shore power, your RV's battery, or propane gas.
An absorption fridge can be either 2-way or 3-way. You can run your 3-way absorption fridge off the battery while driving, hook it up to a portable generator, or switch to propane use.
Can run on propane when you don't have access to electricity.
Less efficient than compressor refrigerators and takes longer to cool down.
Poor Performance if your RV is not level.
It's recommended not to run the absorption fridge on propane while driving due to safety concerns.
4. Residential Refrigerators in an RV
Residential refrigerators in an RV are simply regular home fridges installed in an RV setting. They use a compressor and refrigerant to cool the interior. These units can only run on 120V AC power and require an inverter to run while driving.
Easy to use.
Offer a lot of space for your food storage.
Consume a lot of power.
Inverters required can consume some power and may not provide enough power for your fridge.
Need a large battery bank and a powerful alternator to keep up with the energy needs.
Add a lot of weight and may increase your gas mileage.
RV Fridges That Can Run Off a Battery
Based on the different types of fridges available for RVs, the following RV fridges can run directly off the battery while driving:
3-Way absorption fridges
12V compressor fridges
In contrast, running 2-way fridges, 2-way compressor fridges, and residential refrigerators off the battery requires an inverter to convert the 12V DC power from your battery to 120V AC power, which can rapidly deplete your battery.
Run Your RV Fridge Off Battery While Driving
Now that you know which RV fridge types can run directly off batteries, it's important to ensure your battery has enough power to support your fridge during the trip if you plan on keeping it running while driving.
Determine Your Energy Needs
Start by estimating the watt-hours your fridge will consume per day. Check your RV or vehicle manual for wattage or amperage details. If this information isn't available, refer to the provided table.
Remember that absorption fridges' consumption varies based on the mode (AC, DC, LP), and compressor fridge consumption differs according to size and type.
Typical RV Fridge Specs
12V Compressor Fridge
Inefficient and drains the battery quickly.
Watts and amp vary by style and size.
To calculate the energy consumption of your fridge and other appliances, you can use the following formulas:
Volts x Amps = Watts
Watt-hours = Watts x Hours
For example, if you have a 12V compressor fridge drawing an average of 6A using 12V power, it consumes:
12V x 6A= 72 Watts
If you run this fridge for 8 hours a day, it will need:
72 Watts x 8 Hours=576 Wh per day
Assuming you have a 12V-100Ah lead-acid battery in your RV, you can use up to 600Wh per cycle (12V x 100Ah x 50% = 600Wh), with 50% accounting for the safe depth of discharge. Without additional charging methods, your fridge would quickly deplete the lead-acid battery.
On the other hand, if you have a 12V-100Ah Lithium Iron Phosphate (LFP) battery, you'll have 960Wh available per cycle (12V x 100Ah x 80% = 960Wh), where 80% accounts for the depth of discharge.
It's also important to note that many modern 12V portable RV fridges, especially those with an advanced ECO mode, consume significantly less than 576 Wh over 8 hours. Such 12V fridges can efficiently run off the battery without draining your vehicle's battery while driving.
Run a Fridge on Battery More Efficiently While Driving
As mentioned, RV refrigerators can lead to varying rates of battery drain while on the road. Nevertheless, several charging options are available to keep your battery topped up and prevent it from draining due to a fridge while driving, especially when electrical outlets are not accessible:
1. Solar Power Solution
Solar Power Solution: Solar power solutions involve installing solar panels on your RV's roof and connecting them to a solar charge controller and the battery bank. The solar panels can generate power for your battery even on cloudy days, while a solar charge controller manages voltage and prevents overcharging of the battery.
Solar power can reduce your dependence on propane or shore power and save you money in the long run. Besides, solar power generation is silent and sustainable.
However, this option has some challenges:
You may not always get enough sunlight to power your battery. It’s essential to plan ahead and check the solar forecast before your trip.
The initial costs may include purchasing and installing solar panels, charge controllers, batteries, and wiring.
You'll also need to maintain and clean the system regularly.
2. Vehicle's Alternator
The alternator can charge your battery via a 7-pin connector or separate wire while driving. It’s easy and convenient for all RVs but may fall short in offering adequate power for the fridge continuously, especially with additional appliances in use. And once the engine is off or idle for an extended period, your fridge may stop working or drain your battery.
3. Engine Charge with DC to DC Charger
On-board chargers are more effective than standard alternator charging. Installing an onboard DC-to-DC charger that efficiently maintains your battery level is worth considering.
4. Gas or Solar Generators
Gas or Solar Generators: Portable solar generators act as a backup battery bank for your RV, while gas generators produce electricity through fuel combustion. Solar generators are quiet and don’t emit any emissions but rely on sunlight for recharging. Gas generators can run at any time and typically offer more immediate power; however, they require fuel and emit noise and pollutants.
When choosing the best charging method, it's important to consider factors such as the frequency of travel, power needs, and budget constraints to make an informed decision.
By choosing the right charging method for your RV's power system, you can ensure continuous operation of your fridge and appliances for a seamless and comfortable experience, even in remote locations.
In short, if you equip your RV with a 12V refrigerator or a 3-way RV fridge and ensure that your RV battery can meet its energy needs, you can run your fridge off the battery while driving, keeping food cold and fresh throughout your journey.
Even if your battery cannot support the RV fridge you have, there are still methods like those previously mentioned to help keep your RV fridge efficiently charged.
Alternatively, consider investing in an efficient fridge, such as the 12V RV fridges from BougeRV, for hassle-free travel!
1. Which Cools an RV Fridge Faster: Electric or Propane?
Some RVers report that propane cools an RV fridge faster than electric, while others claim the opposite.
However, the cooling speed of an RV fridge may be influenced by various factors, including ambient temperature, humidity, ventilation, leveling, and load. The best way to determine what works best for you is to test both methods yourself.
2. Will the Travel Trailer Fridge Run off the Battery While Driving?
Yes, it can run off the battery when you're driving if you have adequate power to support it. You should consider the fridge’s energy consumption, the capacity and state of charge of your battery, and the method of charging your battery while driving.
3. Can I Run My RV Refrigerator on Propane While Driving?
While technically possible, it's not recommended to run your RV refrigerator on propane while driving due to the fire risks involved.
Additionally, some states prohibit driving with propane on for safety reasons. If you must use propane, make sure to check local laws before driving with it on, and always turn off the propane supply before entering tunnels, bridges, or gas stations.
4. Does an RV Fridge Need a Battery to Run on Propane?
Yes, it does. Even if you run your RV refrigerator using propane, you'll still need a battery to supply power to the fridge's electronic controls and igniter. Without a battery, the refrigerator won’t work on propane.
5. How Long Will an Rv Residential Fridge Run on a Battery?
To calculate your fridge's battery runtime, follow these steps:
Estimate your fridge's daily power consumption in watt-hours (Wh). For example, let's say it requires 576 Wh to run for 8 hours.
Check your battery's capacity and state of charge. If you have a 100 Ah battery at a 50% state of charge, you effectively have 50 Ah available.
Convert the fridge's watt-hour consumption to amp-hours using the formula: Amp-hours = Watt-hours / Voltage.
Assuming a standard RV battery voltage of 12 volts, your fridge requires 48 Ah for 8 hours of operation (576 Wh / 12V = 48 Ah).
Given this example, with 50 Ah available, your battery could run the fridge for approximately 8 hours, assuming no other loads are drawing power from the battery.
However, it's generally recommended not to drain your battery below 50% to preserve its lifespan, which would reduce the available runtime.
6. How Long Will a 12-Volt Fridge Run on Battery?
The runtime of a 12-volt fridge on a battery depends on the fridge's power consumption and the battery's capacity. For instance, if a fridge consumes 5 amps per hour and the battery has a 100 Ah capacity, then theoretically, the fridge could run for 20 hours. Actual runtime may be less due to efficiency losses, additional electrical loads, operating mode, etc.