There are many styles, shapes and sizes of refrigerators and freezers on the market today. Some are powered by 110 volt AC power from the wall outlet in your home, some are powered by propane and others are powered by 12 volt and 24 volt DC power commonly found in a motorhome RV, semi-truck or off-grid cabin. With so many options to choose from and so many possible applications that deciding which refrigerator is best for you can be challenging.
Here we'll discuss the differences between various types of refrigerator units. We will also discuss when and why you should use a certain type of refrigerator instead of another type which should help you be more informed and make the best decision when you're ready to purchase a new fridge for your truck, RV or off grid camp or cabin.
Standard 110V AC refrigerators that we each have in our homes are great for everyday on the power grid use. There are tons of features built into these units such as ice makers, filtered water dispensers and even cameras and bluetooth to help with grocery shopping. These refrigerators are large and can be very costly. They are also not the best for portable, travel or off-the-grid use as they consume a tremendous amount of power and must be nearly perfectly level during operation. These standard refrigerators should not be used for several hours after transportation which makes them even less of an ideal choice for use in semi-trucks and RV's. While using these standard refrigerators off the grid is possible it is not recommended as doing so does require extra equipment such as a power inverter and a strong charging system which has the ability to satisfy the demand of the inverter.
The best refrigerators for use in your vehicle, off-grid cabin or camp are those which are powered directly by the DC power stored in automotive and deep cycle batteries. These are commonly referred to as 12 volt refrigerators or portable refrigerators. They are built to keep contents cold using power from the vehicle or DC battery without any extra equipment and typically consume a modest amount of power which saves the user money, time and frustration. A 12 volt refrigerator is designed to plug into the lighter socket outlet in cars, trucks and RV's, but many can also be wired directly to the battery or charging system.
Some portable and 12 volt refrigerators look similar to the common ice chest cooler and others are built in the upright style similar to the more common home refrigerator.
The chest style 12 volt refrigerators are great for a wide variety of uses, but most commonly are used when traveling by car. They are also a favorite with EMS crews and those conducting field research where preservation of samples is crucial. These units can be used as a refrigerator or a freezer depending on the thermostat setting. These are often a popular choice because they are so easy to move from the vehicle to indoors where power may then be supplied using an AC to DC power converter. |
The upright refrigerators for semi-trucks, motorhomes, off grid cabins and homes closely resemble a home fridge. These refrigerators are easily installed using just a handful of screws and mounting hardware. They are self ventilating meaning there is no requirement for roof ventilation. These are also thermostat controlled and most require a simple two wire power connection. This style 12volt refrigerator has a small inside freezer compartment sufficient for storing ice cream or frozen veggies. The refrigerator is great for eggs, cheese, milk, cans or 2-liter bottles of soda, orange juice and more. |
Installation and Power
Some chest style and some upright style portable refrigerators are available with what's called Dual Voltage configuration. These units can be operated using AC (alternating current) or DC (direct current). These will have four power wires, two for DC operation and two for AC operation. All of these refrigerators use auto power switching. When running the generator, inverter or are connected to shore power then AC power will be present and the refrigerator will choose AC power mode. When AC power goes away and DC power is available the fridge will automatically switch to DC power mode. By adding a 110V switch inline of the AC power leading to the unit you can force DC operation when AC power is present. Just remember to turn the switch back on when auto-switching mode is desired.