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refrigerator battery

stopper93

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Jun 18, 2022
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i am looking to build a battery to power my refrigerator during storm outages (last year 10 days after hurricane ida) i am planning on getting 1 or 2 panels to power it.
my refrigerator takes about 2.400kwh over 24 hours. I did a 5 day audit using a kwh meter over 5 days and averaged it out.
so the max it registered at once was 600 w, and i am assuming this device is unable to calculate startup surging and would need a 2.500-3.000kw inverter (4x600kw)
so for 24 hour use i would need a battery capacity of 2.500kwh with 900 watts of solar panels? south Louisiana so 5 to 6hours daily is normal with expecting peak need in july -sept so closer to 8 hours of sun. so about 400 w for 8 hour day. am I missing anything?
 
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Your decimal point is off a bit. Seems like you meant 2.4kWh, 600 Watts, 2.5kWh which = 2400Wh, 0.6kW, 2500Wh respectively.
The 600 Watt peak reading may be a defrost heater? The compressor even on a full sized kitchen refrigerator should operate at 150 Watts or less. A 1000 to 1500W quality, low frequency pure sine wave inverter should be enough to operate the refrigerator unless its 30 years old or perhaps one of those overpriced SubZero non-energystar pigs.
Battery capacity of 2.5kWh sounds about right since the battery only has to carry the load at night when the solar panels are not active. A 500 Watt solar panel array would be the bare minimum to produce 2.5kWh per day under good conditions. Probably a good idea to double up and go with about 1000 Watts of solar, since a few cloudy days in a row can cut production in half or less very easily.
 
Your decimal point is off a bit. Seems like you meant 2.4kWh, 600 Watts, 2.5kWh which = 2400Wh, 0.6kW, 2500Wh respectively.
The 600 Watt peak reading may be a defrost heater? The compressor even on a full sized kitchen refrigerator should operate at 150 Watts or less. A 1000 to 1500W quality, low frequency pure sine wave inverter should be enough to operate the refrigerator unless its 30 years old or perhaps one of those overpriced SubZero non-energystar pigs.
Battery capacity of 2.5kWh sounds about right since the battery only has to carry the load at night when the solar panels are not active. A 500 Watt solar panel array would be the bare minimum to produce 2.5kWh per day under good conditions. Probably a good idea to double up and go with about 1000 Watts of solar, since a few cloudy days in a row can cut production in half or less very easily.
yes I did pop the wrong decimal. The refrigerator is a lg french door with bottom freezer. yes i expect the 650 bump was the deforst. so from my reading I have understood to use 4 times the use for a start up compressor. I cant find the specs for my particular refigerator.
 
Can you edit the units or decimal point in your first post? I know what happened and I've done it myself, but I still get confused reading it. Thanks

I'd suggest using a larger battery. I don't live in hurricane area, but I suspect there is likely some cloud cover after the hurricane blows through? I'd probably want 2-3 days of battery so I can make it through the overcast, cloudy days.
If you're going to stick with 1 day of storage, you don't want to use 100% of the pack, you should limit your drain to about 80%

Do you need to plan for winter power outages? You'll get less sun and might need to recalculate your panels.

Overall it seems like a good plan.
Are you going to mount the panels? Or store them away and only bring the system out when needed?
 
Can you edit the units or decimal point in your first post? I know what happened and I've done it myself, but I still get confused reading it. Thanks

I'd suggest using a larger battery. I don't live in hurricane area, but I suspect there is likely some cloud cover after the hurricane blows through? I'd probably want 2-3 days of battery so I can make it through the overcast, cloudy days.
If you're going to stick with 1 day of storage, you don't want to use 100% of the pack, you should limit your drain to about 80%

Do you need to plan for winter power outages? You'll get less sun and might need to recalculate your panels.

Overall it seems like a good plan.
Are you going to mount the panels? Or store them away and only bring the system out when needed?
winter outages are near none existant here. usually less than 12 hours when they do happen. eventually i am going to mount full solar panels but trying to decrease needs for fossil fuel generators that always seem to work poorly.
typically the storm lasts for 20 to 30 hours with with almost clear skys after. but if need be i can cycle 1 hour on every 4 hours. till the sun comes back out. and usually the refrigerator is filled with frozen containers of ice before landfall. so weather I install or pull panels out for emergencies kind of depends on what I buy how heavy and hard they will be to do a pull out or mount. I am considering doing a pull out scenario there is yardage not far away that gets almost continual sun. so my first itteration will probably be 2.5 kwh with 2 24 v 1.25 kwh cells that i can add 24v 1.25kwh cells as finances permit.
 
i am looking to build a battery to power my refrigerator during storm outages (last year 10 days after hurricane ida) i am planning on getting 1 or 2 panels to power it.
my refrigerator takes about 2.400kwh over 24 hours. I did a 5 day audit using a kwh meter over 5 days and averaged it out.
so the max it registered at once was 600 w, and i am assuming this device is unable to calculate startup surging and would need a 2.500-3.000kw inverter (4x600kw)
so for 24 hour use i would need a battery capacity of 2.500kwh with 900 watts of solar panels? south Louisiana so 5 to 6hours daily is normal with expecting peak need in july -sept so closer to 8 hours of sun. so about 400 w for 8 hour day. am I missing anything?
my side by side double door maytag fridge uses 750kwh per year. 750 kwh/ 365 = 2.05kwh per day, 5 days would be 10.25kwh.
if you buy one 250w solar panel, your sun time is about 5 hours / day, but you won't get full power, so 1/2 of 250w x 5 hours = 625wh.
2050wh/625w = 3.25 panels. charging batteries takes a little more power than you put into it. 1000w of solar panels will keep your batteries
charged before the power goes out. once the power goes out, you need batteries to power your fridge during evenings, mornings, night, and
whenever the clouds block the sun. storms tend to happen during evenings or nights, so if the storm hits at 6pm; then your batteries are needed
immediately and are charged. so you need strong enough batteries to last at least until about 10am the next day...16 hours. 2.05kwhx 16/24hours
that's essentially 1.4kwh and your battery could be dead if it isn't strong enough. then when evening comes your battery won't be fully charged
because the solar panels are both charging the battery and running the fridge. So you need more than 1000w of solar panels and a fairly big
battery. if your battery is 12 volts, then 1.4kwh battery is about 110ah. depending upon what the battery is made of, you will probably need about
4 each 110ah batteries and maybe 2000w of solar panels. you will also need a battery charge controller. you can buy trojan lead acid style batteries relatively cheap if used. i think the ones i saw for sale were 190ah batteries, which might be the equivalent of a good 100ah LiFePo4 battery...but 4 ought to last you I'm guessing.
 
thats about what mine saied and is about what i found mine was 2.2 kwh/day when tested and averaged over 5 days.
my side by side double door maytag fridge uses 750kwh per year. 750 kwh/ 365 = 2.05kwh per day, 5 days would be 10.25kwh.
if you buy one 250w solar panel, your sun time is about 5 hours / day, but you won't get full power, so 1/2 of 250w x 5 hours = 625wh.
2050wh/625w = 3.25 panels. charging batteries takes a little more power than you put into it. 1000w of solar panels will keep your batteries
charged before the power goes out. once the power goes out, you need batteries to power your fridge during evenings, mornings, night, and
whenever the clouds block the sun. storms tend to happen during evenings or nights, so if the storm hits at 6pm; then your batteries are needed
immediately and are charged. so you need strong enough batteries to last at least until about 10am the next day...16 hours. 2.05kwhx 16/24hours
that's essentially 1.4kwh and your battery could be dead if it isn't strong enough. then when evening comes your battery won't be fully charged
because the solar panels are both charging the battery and running the fridge. So you need more than 1000w of solar panels and a fairly big
battery. if your battery is 12 volts, then 1.4kwh battery is about 110ah. depending upon what the battery is made of, you will probably need about
4 each 110ah batteries and maybe 2000w of solar panels. you will also need a battery charge controller. you can buy trojan lead acid style batteries relatively cheap if used. i think the ones i saw for sale were 190ah batteries, which might be the equivalent of a good 100ah LiFePo4 battery...but 4 ought to last you I'm guessing.
thats about what mine said, my average was slightly higher. so i understand there is about 25 percent loss in conversion and storage plus the inverter draw. is it closer to 50 percent loss? or just assumption that my stucture wont allow for 100percent conversion for majority of the day and real world is closer to 50 percent ?
 
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