The refrigerator/Freezer is the only appliance to save our food during camping, tailgating, kayaking, etc.
Adding a generator to your inventory would allow you to run not only the other appliances but also your refrigerator so you can save food.
In order to provide detailed answers about what size generator do I need to run a refrigerator/freezer? How many watts does a refrigerator need? How to calculate them? Etc., We have tested multiple refrigerators/freezers with a variety of generators.
The size of the generator depends on the size, model, and features of the refrigerator/freezer. Typically a 1000-watt generator would be enough to operate a mini-fridge, however for medium and large sizes with multiple functions like an icemaker, dispensers, etc. you will have to purchase a unit of 2000 and 5000 watts respectively.
How Many Watts Does a Refrigerator/Freezer Use? – (Starting/Running Watts)
Before starting the calculations we have to know about the starting and running watts of the both refrigerator and generator.
Starting watts: The number of wattages a refrigerator/ freezer required for initial startup, they could be anywhere between 200 – 2000w depending on the size.
Also, we have to figure out the starting wattage of the selected generator as well for better compatibility.
Running watts: The number of wattages a refrigerator/ freezer needs for constant running, running watts could be between 50 – 1200w depending on the size. like starting wattages we also have to calculate the running wattage of our generator as well.
Wattage Comparison Table of Refrigerator/Freezer by Size
|Model & Type||Starting Watts||Running Watts|
|Mini Fridge||50 – 100||150 – 200|
|Standard Mini Fridge||75 – 150||300 – 400|
|Big Mini Fridge||100||400|
|Modern Fridge (Standard Energy Star Fridge 2001 – till know)||100 – 400||150 – 600|
|Counter Top Fridge||160||240|
|Side By Side Fridge||650 – 800||1000 – 1100|
|Old Fridges (1992 – 2000)||200 – 800||300 – 1300|
|Mini Glass Refrigerator||140||210|
|Deep Freezer||300 – 500||530 – 750|
How to Calculate the Refrigerator’s Wattages Manually (Step-by-Step Guide)
STEP 1: Calculate the starting and running wattages of the refrigerator.
Like any appliance, a refrigerator has two wattage ratings one is starting (for initial startup) and the other is running (for constant running).
For getting these two ratings, you have to skim the user’s manual or the energy label on the back of the refrigerator.
Energy labels have a rating like voltage/frequency, current (amp), Volts (v), Refrigerant, Dimensions, etc.
Below is the video of espare’s to get a better understanding of energy labels.
STEP 2: Use the wattage formula for calculation and add 20% extra wattage on top.
If you got starting and running watts in watts then you don’t have to use the wattage formula for conversion, however, if you have found in amps then you have to convert them. Below is an example for better clarification.
I.e. A 120V refrigerator consumes 8A for starting and 6A for running.
Watt = Amp X Volt
- Watts = 6 x 120 = 720 watts for starting
- Watts= 4 x 120 for 420 watts for running
Know you got close to accurate wattage ratings; your next task is to get a generator for this.
For that, you have to add 20% extra wattage to the refrigerator wattage due to the power losses.
- 720×0.2(20%) + 720watts = 864 Watts (starting)
- 420×0.2(20%) + 420watts = 504 watts (running)
Hence, the above refrigerator can be run with a 1000 watts generator unless you are going to pull some extra wattage for other appliances.
Note: The above calculation is made for the refrigerator, if you want to operate multiple appliances and refrigerators as well, follow our guide.
How Long to Run Generator for Refrigerator?
A generator could run a refrigerator or fridge for about 12 hours unless it is out of fuel, however, 1 – 3 hours is a recommended runtime to save both food and fuel. Also, a generator must need a break after a few hours to work perfectly for years. I use to run the refrigerator for 1 hour right after 3 hours to keep food safe.
Can a 2000 Watt Generator Run a Refrigerator?
It depends, a medium-sized refrigerator with 1800 starting and 1000 running watts couldn’t be a problem for a 2000-watt generator, however, a jumbo-sized refrigerator with 2000 – 2500 starting and 1500 – 1700 running watts couldn’t be operated with a 2000 watts machine.
Here is the list of our selected 2000 watt generators.
Can a 1,000 Watt Generator Run a Refrigerator?
A standard-sized refrigerator with 900 starting and 500 – 6700 running watts can operate smoothly even with a solar generator as well (check out our guide about top solar generators for refrigerators), however, you don’t have extra wattages to run other appliances.
Some Important Things Should Be Considered Before Making the Buying Decision.
Recommended Guide What Size Generator to Run Sump Pump?
Frequently Asked Questions – FAQs
Yes, you can plug directly your refrigerator into a portable inverter generator, since the larger generator doesn’t have direct ports because of the higher THD levels you can’t operate your refrigerator directly from them instead you can install a transfer switch.
Yes, if both refrigerators are compatible with a 3000-watt generator you can operate them safely. Like if the running and starting wattages of both refrigerators become 2000 and 2500 respectively, you can run them smoothly by shutting OFF the other appliances.
Yes, in fact, an inverter generator produces lower THD levels to avoid voltage fluctuations.