chest freezer kwh in full day

Does any one have real results on a small 4-7 cf chest freezer where I live it doesn't get above 85°f we have snow from nov to July usually.
200ah LiFePO4 24v Electrodacus Sbms40 quad breaker chest freezer to fridge- Samlex PST 1524 - Samlex pst3024 - 1hp shallow well pump-Marey 4.3 GPM on demand waterheater - mama bear Fisher wood burning stove, 30" fridgarair oven ,fridegaire dishwasher Unique 290l stainless D.C. Fridge-unique 120l portable fridge/freezer
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New freezers tend to be pretty good, use the provided energy rating. You might have to do the math to figure out the per day usage, but it's simple stuff. Most use less than 1KWh and as you have given a temperature range, I will assume the freezer will be subject to the temperatures, hopefully not the snow!
I can't recall the exact problem, but some freezers don't work properly when they are subjected to ambient temperatures below freezing. I suspect frost free freezers have issues with melting the ice from the coils...
- Assorted other systems, pieces and to many panels in the closet to not do more projects.
A straight refrigerator (no freezer section--or your do not use the freezer) and a straight freezer should work fine in cold rooms/weather--From what I understand, I live in a moderate temperature area and only have a few days of frost every year--at best.
-Bill
Conext XW6848 with PDP, SCP, 80/600 controller, 60/150 controller and Conext battery monitor
21 SW280 panels on Schletter ground mount
48v Rolls 6CS 27P
the new standards drop every year benefiting us all.
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada
Regarding conventional AC freezers, some will not last long in ambient freezing temperatures because of motor lubrication issues. Some old freezers in barns around here had heating blankets on the motors. If you are looking at a new freezer, just look at the spec sheet... there will be a description of the ambient operating temperature limits.
Finally, the OP's signature shows a MSW inverter. That may or may not work out too well... some motors don't get along with some MSW inverters (not all MSW waveforms are the same shape). Motors today (and their windings) are made as light as possible for efficiency as well as cost. The thin windings may not be able to dissipate the extra heat caused by a MSW waveform.
--vtMaps
Nice!
For others interested, we've had people here who suggest an external thermostat and probe aren't necessary with some chest freezers the thermostat can be adjusted to fridge temperature ranges, Not simple and mostly unmarked needing some trial and error. Can't think how to search for that thread now. I believe there was a link or 2 to beer brewer's forums...
- Assorted other systems, pieces and to many panels in the closet to not do more projects.
My chest freezer is a magicchef, ~10 years old. Very inefficient, it has coils on the backside to dissipate heat (static, no fan) as opposed to the newer freezers that have 4 walls that get hot to get rid of heat. Mine is 7 cu ft and uses around 1.3kwh per day, if I remember right (measured with kill o watt meter but written down in the great black hole of my mind). I have been thinking of dumping it and getting a sundanzer DC model.... I hear they use only 1/3 of that. But I have the great misfortune to live in Hawaii, of all the out of the way places. You'd think the post office never heard of us, judging by the cost to ship anything here. I guess I will have to commiserate with my pina colada under the swaying palms tonight, damn.
aloha,
walt
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada
http://members.sti.net/offgridsolar/
E-mail [email protected]
http://forum.solar-electric.com/discussion/21072/powering-two-steca-fridge-freezers-from-a-48-volt-battery-bank
And using a small MPPT charge controller to drop from 48 VDC battery bank to 12 or 24 volt battery -> freezer.
-Bill
In the end, I suggest that you do "both designs" on paper and see what works out best for you.
-Bill
Thanks, Hill Country. The Steca's have an upper voltage limit of 31.5V... hmmm. The system I'm building will use 20 NiFe cells, and I think the absorb voltage will be just over that at around 33V... by dropping out one cell and running a bank of 19 in series I would be at 31.35V, just under the Steca's limit but still doable. Interesting. I too am thinking of mixing and matching appliances (some ac, some dc).
Just Starting, I did the same thing, bought an off the shelf a/c chest freezer (14.7cu ft) and used a Johnson Controls digital temp controller to turn the rig into a fridge. It works well, with a couple caveats; the freezer was never designed to be used as a fridge, so condensation collection on the bottom is problematic. I have to sop mine up with a towel every other week or it starts getting smelly in there. Also, the compressor hump/box inside the fridge is wonderful as a place to store milk and other heavy bulky items on top of, like a shelf, so you don't have to reach in all the way to the bottom... so it gets used a lot, but its STEEL on mine and after 1year there are some rust spots appearing. Can't get away from it, will have to shut down the fridge and repaint or glue on a rubber tray on it or something soon. Energy wise it is awesome, best thing I've done so far and made the biggest dent in my power bill.
...so condensation collection on the bottom is problematic...
So I guess a frost free model? I think standard freezer have a drain plug in the bottom.
- Assorted other systems, pieces and to many panels in the closet to not do more projects.
Also, keep in mind the operating temperatures for these units are from 50 deg. F to 109 deg. F. Not sure what would happen if you are below the minimum operating temperature. Just something to consider.
-Bill
Not different power maybe unless you lose your inverter to lightning or if you want to shut down the inverter while you are away because of lighting. I have a friend who uses his to drive to Costco 80 miles away in summer.
Lot's of other reasons someone offgrid might decide being the cheapest is not the best. I know that cost always seems to be the driver here, but from my perch looking back it really is only part of it offgrid.
http://members.sti.net/offgridsolar/
E-mail [email protected]
Does a frost-free model use more power?
https://www.energystar.gov/productfinder/
You can find auto-defrost 10 cuft upright freezers in the 400 kWH per year range (1.1 kWH per day). 16.6 cuft are around 430 kWH per year (1.2 kWH per day).
For me, it ended up being better for our family to spend a bit more on electricity with auto defrost vs having to defrost the thing once or twice a year.
Frost Free units do seem to use a bit more energy (on average)--But the big deal is that they will run a defrost cycle about 2 times per day (at least the ones I have seen). The defrost cycle can take upwards of 600 Watts for a period of time while defrosting (vs the average of 120 Watts for running the compressor).
One of the members here tried disconnecting the defrost heater and found that the evaporator will begin to ice over and block airflow in as little as 24 hours. Which will "kill" efficiency.
If you can live with a chest freezer (or chest refrigerator conversion)--A 15.6 cuft manual defrost freezer is rated at 275 kWH per year (0.8 kWH per day as freezer or ~0.25 kWH per day as a refrigerator conversion).
The downside with almost all current fridge/freezers is that the standard induction motor compressor needs over 600 VA from the inverter just to start.
If you choose to go with a 12/24 VDC direct cooler or a 120 VAC unit + ac inverter + battery bank + larger solar array--Your choice.
If your power needs are very small otherwise--A DC system may make more sense for you. If your power needs are larger (well pump, lighting, cooking, washer, etc.), then a full 120/240 VAC solar power system may be a good choice.
-Bill
Condensation is an issue, yes. I am vegan, although my family is not... but for me, the fridge needs to be just above freezing, but as close to it as possible so that my 7 lb bag of carrots from costco and all my greens purchased once a week from farm fair last as long as possible... my organic kale will usually last about a week in my converted fridge and at times I have kept them 2 weeks and they seemed fine. The bag of carrots, several months easily. But in order to get down that low, I have mine set at 36F in the winter, 35F in the summer, I am in hawaii so not enough temp variation, but enough that I see more ice if I don't do this) with only a 2 F 'dither'. While this might seem high, in actual use the temp seems to hover very close to 36F and at night enough ice forms on the very bottom of the fridge to adhere to the walls and my every other week sopping up with towels ritual is also a 'chip the icebergs' off the wall ritual. The temp stratifies according to the air masses and the digital control's temp probe is about halfway down the box, so the very bottom of the fridge is just cold enough to freeze things slightly if they remain there a long time, although bottled stuff never freezes as it does not get cold enough to freeze anything with solutes in it.
Although mine does have a spigot/drain on the bottom as well, I never use it as it sits in my kitchen and I don't want to run a long hose to it. Also, the condensate level never gets very high so I don't know how useful a drain would be. There is usually a bit of ice frozen in that drain as well (on the inside).
The odd thing was we defrosted the chest freezer twice a year and when I let it do it's final defrost I noticed there must have been a LOT of ice in the walls and lid as they had condensation on them for 3 days and are still dripping water out after 5 days, so there must have been a lot more ice inside the walls of the freezer, which I hadn't considered and I am sure wasn't helping in the power usage. So overall the frost free might help us. The last time it was off for a couple of days was when we moved in to this house 10 years ago now...
I will be curious to see how it compares after a week, it looks to be right about 1 kWh a day right now and our old one was about 1.4 kWh a day.
Thank you for your comments.