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yuanggitssac
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# Posted: 18 May 2012 01:33am
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i been looking for a fridge when i build my cabin. iv looked a propane fridge and they seem like they start at 1000.00, i found a electric mini fridge at walmart http://www.walmart.com/ip/Igloo-3.2-cu.-ft.-Refrigerator-and-Freezer-Stainless-Steel/ 15162427 does anyone know how many solar panels or solar setup i would need to run this fridge 24/7? thanks everyone 
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VTweekender
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# Posted: 18 May 2012 07:51am - Edited by: VTweekender
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I think you would really have to calculate what other devices you would be using as well, such as lights, TV , etc.....as I don't think you would dedicate a system to just the fridge.
Here is a calculation I did for mine that I will be putting together. I will be running a smaller mini fridge , a 10" LCD TV with roof antenna, 2 CFL 25 watt lights , a small microwave , radio , water pump ,charging cell phone. On less than normal use to conserve I came up with about 500 watts in panels, a 30 amp charge controller, a 1500 watt pure sine wave inverter and 2 deep cycle batteries 200 Amp Hour each. The system will cost me about $2,500 or so.
But to answer if only the fridge, I would say 160 watt panel, 15 amp controller, 1000 watt inverter and a 200 AH battery should do it. The fridge will draw about 60-80 watts but not run all the time as it reaches temp, if you only open it 4 to 6 times a day quickly it won't run as much, probably only run about 4 or 5 hours a day. The 160 watt panel with 3 good hours of sunlight (which is about average) will get you 480 watts to use daily, if the fridge runs 5 hours at 80 watts you will use up 400 watts. Note, the freezer draws a lot, I will be using one thats just a fridge myself.
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ShabinNo5
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# Posted: 18 May 2012 08:46am
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Will you be keeping the fridge cool all the time, or just when at the cabin (assuming it is a weekend retreat)?
If you are using the cabin as a weekend retreat, GoalZero may have an option for you. We have purchased their "Yeti" system. I opted for this system because it is the closest thing to "plug and play" I could find.
http://www.goalzero.com/shop/p/138/Yeti-Solar-Generator-Kit//
Last week was our first week with the system, so I cannot provide a detailed review, but so far it has worked flawlessly and is much quiter than the gas generator.
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NWCabin
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# Posted: 19 May 2012 05:27pm - Edited by: NWCabin
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Here is a fridge that has a better energy consumption rating and is a little bigger, the Magic Chef 4.0 cubic ft.
http://www.homedepot.com/h_d1/N-5yc1v/R-100245583/h_d2/ProductDisplay?catalogId=10053 &langId=-1&keyword=magic+chef+4.0+cubic+feet&storeId=10051
As part of your solar system, you'll need an inverter that will handle the start up surge. One of the key points is that you will need an inverter that can handle about 8 times the rating of the refrigerator to get it started.
So in the case of the Magic Chef, which is labeled as needing 120W, you'd need to be able to handle 960W of startup surge. Also, of course, this is someone's rule of thumb and not a test of the exact model of refrigerator and inverter working together.
I can tell you from my own experience the Magic Chef will not start on a MorningStar SureSine, which is rated at 300W continuous and 600W surge. I'm in the middle of shopping for a new inverter and that is how I came across your thread.
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groingo
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# Posted: 22 May 2012 11:51am
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The fridge you are looking at will pull between 150 to 75 watts, 150 when it starts and then it will edge down to 75 once running....and they run a lot because they are poorly insulated.
What you can do to reduce run time is to simply place some one inch foam sheeting around the sides and top and rear if possible.
Inside you can do the same thing depending on how much of the fridge you actually use, by reducing the unused space inside you reduce the area it is trying to cool....less run time.
Finally, if your fridge is nearly empty, put some containers of water inside the fridge, that will help it stay cool with less effort.
Best advise though, if you a have a cool water supply near by keep your food in it or in a water filled cooler....you need temperatures below 42 degrees to safely keep food for any length of time, but eliminating the fridge from the equation was the smartest thing I ever did.
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Anonymous
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# Posted: 28 May 2012 11:59pm
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Shabino5 - would love an update if possible as am considering the goal zero yeti as well for weekend summer cabin for refrigerator. Thanks.
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jbos333
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# Posted: 29 May 2012 07:06am
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Is anyone using a small chest freezer converted to a refrigerator? Those are supposed to be ultra-efficient as far as keeping the cold in, and not running as often.
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razmichael
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# Posted: 29 May 2012 08:02am
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I don't really think the Yeti is the best solution for a cabin (let alone to run a fridge). The product is well put together into a convenient system (plug and play as described) but you are paying a large premium for that integration with components that are not that powerful. It would cost far less to put together a similar system from components and all you would really be giving up is the portability and integration (which does has value if you need that functionality). The battery is only 100amp-hr so only really gives you 50 amp-hrs of usable power maximum and the 60 watts of panels would be hard pressed to replace any constant use. Using some of the fridge power examples being provided in the thread; ignore start up and consider 80 watts to run about 5 hours a day thus 80*5/12*1.1 (last value is a 90% efficiency of the inverter) and you will use about 37 amp-hrs a day. 60 watts of panels might be able to keep up with this under perfect conditions (barely) but anything less then you would be slower running down the battery. And this assumes no other use of the system. All these calculation are rough estimates but would raise an alarm for me if I thought about using this system to power a fridge and a few other things (especially as it costs $2k). Unless you need the portability, you could put together a much more capable system for a fraction of the cost. None of this is meant to bad mouth the GoalZero product - just note that, depending on your needs, it may not be the best or most cost-effective option.
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Renegaderh
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# Posted: 20 Aug 2016 05:53pm
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I know this is an old thread but I have a question related to it. I have a 400 watt ( 4 100 watt panels) solar system with a 2000 watt inverter and a 30 amp charge controller. It's hooked up to 4 deep cycle marine batteries. Should this run a mini fridge and then some? Last summer I noticed that when running the fridge and a portable swamp cooler ( 170 watts) I'd have to turn one off because my inverter was falling below the needed out put. Is there something different I need to do or do I need more watts? I can add another panel to this system I.
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MtnDon
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# Posted: 20 Aug 2016 06:19pm
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My first guess is that you run yohr batteries ina 12 volt configuration. The batteries can not supply the amps needed for the watts being demanded out of the inverter. Adding panels will not help.
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Renegaderh
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# Posted: 20 Aug 2016 09:51pm
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Is there a way to change that? This is my first time using solar so I'm learning as I go. In an earlier post someone mentioned using a 160 watt panel, a 1000 watt inverter to run a fridge, that's what got my attention since my set up seems "bigger". Thanks for the help though.
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Renegaderh
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# Posted: 20 Aug 2016 09:56pm
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How do I change the set up? This is my first time with solar so I'm learning as I go. My set up does currently run just about everything else. 19" tv,bluray, stand mixer, even the swamp cooler ( all day and for a few hours at night). Would really like to have a small fridge especially during the hot Arizona summer. Thanks for all your help.
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creeky
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# Posted: 21 Aug 2016 08:45am
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you might want to look at your inverter. if its older and modified sine wave it might be the problem. it could be drawing 35w/hr by itself. msw has trouble with compressor start up draw.
also. there are some new small fridges that use under 200w/day.
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Renegaderh
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# Posted: 21 Aug 2016 11:09am - Edited by: Renegaderh
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This is my inverter. It was part of an off grid kit I purchased from Grape Solar. Not sure if it's a msw, I will have to check . It's a Xantrex prowatt 2000.
I checked its a pure sine wave inverter.
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Renegaderh
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# Posted: 21 Aug 2016 11:12am
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The fridge I had was a Haier 1.7 cubic foot mini fridge. Not sure of the watts it used.
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Renegaderh
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# Posted: 21 Aug 2016 11:53am
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Is this the configuration I should use?
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Renegaderh
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# Posted: 21 Aug 2016 12:27pm
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Crossing the negative and positive scares me a lot. Yikes.
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MtnDon
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# Posted: 21 Aug 2016 01:15pm
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Quoting: Renegaderh ... I'd have to turn one off because my inverter was falling below the needed out put.
What exactly do you mean by that? Did the inverter alarm buzzer sound? That is what I interpreted that to mean. If so that means the batteries were unable to supply the amperage the inverter needed to work without the battery voltage dropping too low.
Lead acid batteries have a problem delivering a continuous stream of high amps without suffering from severevoltage drop. Gets worse as batteries age. The voltage drop can also be caused by too small a wire gauge between batteries or from batteries to inverter.
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LastOutlaw
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# Posted: 21 Aug 2016 01:25pm - Edited by: LastOutlaw
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I do use the chest freezer modified to be a fridge. I'm very happy with the results. I think it uses about 300 watts a day total on my kill a watt.
If i turn it all the way up it will even make ice in trays laying in the bottom. From what I've read if it is kept full frozen foods can be stored deep in it and cool foods near the top just fine.
So far I have only been using mine during visits for a week or two at the most at a time.
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Renegaderh
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# Posted: 21 Aug 2016 01:59pm
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Yes, the alarm would sound. It goes off when the read out gets down to 11.0 . I forget what that number means.
I changed the battery configuration and I'm getting 25.1 volts on the charge controller but now the inverter is givung off the over voltage error code.
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Renegaderh
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# Posted: 21 Aug 2016 02:01pm
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This is my battery set up. The black and red cables run to the inverter. They look pretty heavy duty.
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MtnDon
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# Posted: 21 Aug 2016 03:26pm - Edited by: MtnDon
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11 = the battery voltage. Too low to operate at the demands being placed on theinverter.
With the battery reconfiguration that gives 25 volts you are lucky tbe inverter is just giving an error message and has not burnt up!
The inverter / battery cables are probably contributing to the problem. Too small, too long. That depends on how many watts you are trying to pull fromthe inverter. A kill-a-watt meter would let you measure actual demand. But if the fridge is a compressor type it will have a start up surge many times the running power.
In order to solve this you need toknowthe total watts being used... then calc tne amps needed to pull out of the batteries for that.
I have the same inverter in a trailer. We use 2/0 gauge cables to reduce voltage drop to be more managable. The alarm still sounds on 1000 draws & that is because the lead acid batteries sag after a short time.
A 24 volt system ismuchbetter but needs a 24volt inverter. Hope you didn't toast yours.
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Renegaderh
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# Posted: 21 Aug 2016 04:06pm
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Thanks MtnDon! No, I didn't toast it, whew! I shut it off as soon as the error code started flashing . I'm back to the standard set up for now.
Ugh, I hate doing the math. .lol. it is not my strong suit and trying to understand watts and amps gives me a nosebleed . Haha. Thank you for all your help. I'm gonna go do so math now. Boo..
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Renegaderh
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# Posted: 21 Aug 2016 04:15pm - Edited by: Renegaderh
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Found these on eBay. Any thoughts ? The silver one is almost 800.00 the green one is about 400.00 both are 3000 watt 24 volt inverters
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creeky
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# Posted: 22 Aug 2016 10:49am
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You don't need a new inverter. The inverter is fine. I run a 10 cu ft fridge off of a 1200w inverter.
As I pointed out, your inverter is using about 600 plus watts a day. Your fridge. If it's an older Haier. yup. the 1.7 uses 1kw/day. Give or take.
Try putting it in the coolest area you can.
Your battery pack is too small. And possibly too old. Those marine starter/deep cycle batteries don't last long in the situation you are using them in.
Focus on your batteries and wiring. Everything else looks okay.
Is your charge controller MPPT? or PWM?
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Renegaderh
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# Posted: 22 Aug 2016 11:20am
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This is my charge controller. Not sure about the mppt or pwm. What kind of batteries do I need and how many?
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Renegaderh
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# Posted: 22 Aug 2016 11:28am
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My inverter is a pure sine wave inverter.
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Renegaderh
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# Posted: 22 Aug 2016 12:33pm
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I bought the fridge in 2015 brand new.
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creeky
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# Posted: 22 Aug 2016 02:51pm
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you cc is pwm.
even very tiny fridges can draw a lot of energy. your 1.7 actually uses more energy than my 10. there are some new small fridges that use under 200 kw/yr. look at the energy guide rating.
your inverter is a good inverter. no doubt. yours claims to be .8a/hr. so 250w / day. that's real good.
You need to look at 3 things.
one. your wiring. look up the tables for wire size. if you run 10w inverter, 170w swamp cooler and 200w surge on the fridge. call it 400w. at 12v. 40 amps is a realistic #.
If you were to max out your inverter at 3000w you'd be drawing 250 amps on surge. at 2000w 160 amps. your wiring needs to reference these #s.
Two: your battery bank. obviously if you're running out of power you need a bigger bank. break down your loads. multiply by 24 hrs. now you know what you need daily.
what is that number?
batteries are a contentious issue. I recommend lithium. but it they can be a bit dear.
your 400w of panels should be good for 1.2kw/day.
and 3. your charge controller. an mppt could give you a bit more solar input. probably not a concern yet.
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Renegaderh
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# Posted: 22 Aug 2016 03:19pm
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Awesome. Thanks for all the input. I've got some research to do and some math ( bkech) I can't tell you guys how much I appreciate the feedback. I've been living off the grid for about a year and half now and it's really great but what I'm spending for ice several times a week in the summer would more than pay for some wiring upgrades and new batteries. Thanks again!
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