The refrigerator backup power run time test, is probably the most valuable test to have information on. I became interested in this in 1996, while experiencing a long term power outage. I had a 300 watt power inverter and 12 volt, 100 amp hour battery. Since the refrigerator only pulled 110 watts, I falsely assumed I could run the frig. Wrong, trying to start that load blew out the power inverter. Since then I have characterized the electrical demands of the typical US kitchen frost-free refrigerator, and it is surprising! Obviously, the designers of such products assumed that unlimited power is available to start the frig. So, to start the kitchen frig that only draws 120 watts while it is running, but to cleanly start it, I have experimentially determined you need a generator output power of 2,500 watts for 10 seconds. During that 10 seconds, the voltage cannot sag. This is a worst-case number. There's more. With a room temperature of 77F/25C degrees, the compressor runs 50% of the time. Depending upon how many times you open the frig door, on average the frig goes into a defrost cycle 3 times a day. Defrost is performed by a 600 to 720 watt heating element that stays on for 5 to 20 minutes. This averages out to 1.74 kWh over a 24 hour period. The frig used in the video does not have a defrost, it has a size of approximately 5 cubit feet, whereas the average US kitchen refrigerator is 18 to 20 cubit feet. If you are hoping to run the frig 24/7, you will need at least 1,200 watts worth of solar panels just for the frig. This is a near worst-case number, and takes into account some overcast days.
Bigger frig's are a lot more energy intensive. Several times what you experienced with the little one. Not opening the door helps and have it prefilled/cooled. During times with good sun, you could hook up a single 200W solar panel to your Bluetti and run that little frig. 24/7 with no problem. We have a second refrigerator in our RV outside kitchen and I do it all the time, when we don't want to or can't run a generator.
Excellent video. I wonder if you repeated the test with a filled refrigerator that maybe it would run longer? It may cycle even less trying to maintain temperature with it filled versus dead air space. Thanks again for your time and effort putting these videos together.
Thank you for this test. Question, does your dorm refrigerator have a freezer section? I believe that would add additional stress on the system. From your video I believe that particular dorm refrigerator is very efficient. Like others have mentioned it would likely run longer with contents typical of a home unit. I look forward to your re-test with the real deal.
Go for the real test, I used a Bluetti AC180 and ran a test with my full size 15 year old Kenmore refrigerator, it ran for over 12 hours. The compressor start up was 1040 watts then settled down to about 105 to 165 watts. The actual run time was less than 9 hours according to my watt meter. I plan on building my own system with more capacity, as the AC 180 only has 1152 Wh with about 1010 usable. It's rather costly to get into solar, but I can see the advantages over the long run. Are you still satisfied with your inverter from Genetry Solar. Best regards...
A full fridge/freezer is more efficient than an empty one also, if you plan on opening and closing the door... as the contents will retain the interior temperature a lot better than just the air within it.
The refrigerator backup power run time test, is probably the most valuable test to have information on. I became interested in this in 1996, while experiencing a long term power outage. I had a 300 watt power inverter and 12 volt, 100 amp hour battery. Since the refrigerator only pulled 110 watts, I falsely assumed I could run the frig. Wrong, trying to start that load blew out the power inverter. Since then I have characterized the electrical demands of the typical US kitchen frost-free refrigerator, and it is surprising! Obviously, the designers of such products assumed that unlimited power is available to start the frig. So, to start the kitchen frig that only draws 120 watts while it is running, but to cleanly start it, I have experimentially determined you need a generator output power of 2,500 watts for 10 seconds. During that 10 seconds, the voltage cannot sag. This is a worst-case number.
There's more. With a room temperature of 77F/25C degrees, the compressor runs 50% of the time. Depending upon how many times you open the frig door, on average the frig goes into a defrost cycle 3 times a day. Defrost is performed by a 600 to 720 watt heating element that stays on for 5 to 20 minutes. This averages out to 1.74 kWh over a 24 hour period.
The frig used in the video does not have a defrost, it has a size of approximately 5 cubit feet, whereas the average US kitchen refrigerator is 18 to 20 cubit feet.
If you are hoping to run the frig 24/7, you will need at least 1,200 watts worth of solar panels just for the frig. This is a near worst-case number, and takes into account some overcast days.
Bigger frig's are a lot more energy intensive. Several times what you experienced with the little one. Not opening the door helps and have it prefilled/cooled. During times with good sun, you could hook up a single 200W solar panel to your Bluetti and run that little frig. 24/7 with no problem. We have a second refrigerator in our RV outside kitchen and I do it all the time, when we don't want to or can't run a generator.
Thanks!
Glad you enjoyed it.
Excellent video. I wonder if you repeated the test with a filled refrigerator that maybe it would run longer? It may cycle even less trying to maintain temperature with it filled versus dead air space. Thanks again for your time and effort putting these videos together.
Thanks. I am still trying to talk my wife into letting me use our full size fridge. I am curious too.
@@OurBlackCatCottage Just use filled water jugs and/or bottles. No risk of spoiling.
Thank you for this test. Question, does your dorm refrigerator have a freezer section? I believe that would add additional stress on the system. From your video I believe that particular dorm refrigerator is very efficient. Like others have mentioned it would likely run longer with contents typical of a home unit. I look forward to your re-test with the real deal.
It does have a small freezer. Next one will be a full size with food in it. As soon as I get the OK to do it.
Does a dorm refrigerator have a auto defrost cycle ? Would a full size refrigerator have a higher ( amperage ,wattage ) need to operate?
Not sure about the auto defrost cycle . A full size one would use more energy.
Go for the real test, I used a Bluetti AC180 and ran a test with my full size 15 year old Kenmore refrigerator, it ran for over 12 hours. The compressor start up was 1040 watts then settled down to about 105 to 165 watts. The actual run time was less than 9 hours according to my watt meter. I plan on building my own system with more capacity, as the AC 180 only has 1152 Wh with about 1010 usable. It's rather costly to get into solar, but I can see the advantages over the long run. Are you still satisfied with your inverter from Genetry Solar. Best regards...
I am planning on a full size fridge test as soon as I can. My Genetry Solar is a beast. Solid and can run hard for hours if not days with no issues.
@@OurBlackCatCottage It's on the top of my list when I get my funds right. Thanks...
A full fridge/freezer is more efficient than an empty one also, if you plan on opening and closing the door... as the contents will retain the interior temperature a lot better than just the air within it.
And this was already really efficient.
Stopped at “my wife would not let me…”
Glad you enjoyed the video. Thanks for watching!
@@OurBlackCatCottage I didn’t watch it.
@@OurBlackCatCottage Well, if visskiss didn't watch it, I did, and I sure enjoyed it. Thanks for posting this!