how much solar for mini fridge in van??

[carolineewatsonn]

Hi! I'm so happy I found this forum because I'm pretty much clueless. I'm thinking about long term travel in my van and need some help figuring out how much solar I need. Even with weeks of research I'm still confused!
My main thing is I need a mini fridge. I cannot afford the dometic one that seems popular, so I was going for a cheap dorm style fridge, specifically the Insignia 3.0 cubic ft mini fridge. I see on Best Buy it uses 1.5 amps and 115 volts, which I believe means about 172 watts. Does that mean I can buy a 175 panel and be good to go? or is it not that simple and I need more wattage than that? An article I read says a 3.1 cubic ft mini fridge would need like 400 watts, not 175, so am I missing something or did I just find an energy efficient fridge?

Also, what kind of battery and inverter would I need? On that same article it said 300 amp battery and 2000 inverter. Do you think that's correct or, because I have a more energy efficient fridge, I could go with less? like, I don't know, 200 amp and 1000 inverter?

Any help you could give would be SO appreciated!!!

 

[ghostwriter66]

So according to the specs the fridge draws 16A at 12V to operate. Now I have no idea if that is 16A constant or just 16A when the compressor kicks on .. I know most of the frdiges we have is 10-20A while the compressor is on and then literally NOTHING when its not --

But either way ... just throwing a 175W (16A) panel up there would not suffice -- since a 175W panel is going to produce at best 160 on a good day and ONLY when the sun is shining directly on it - which is only about 5 hours a day on a yearly avg. So now what do you do about the other 21 hours of non-sunlight ...

SO a couple of ways around that -- YEP add more panels ... also add a DC-2-DC converter that will take power from your alternator while you drive and charge your batteries - to run your fridge ...

BUT the issue is going to be when you are not driving for a couple of days - you will need to rely on the SUN and the Batteries to accomplish this...

BUT I think that 16A number is high ... I will check one of the smaller fridges here at work and see what it actually draws during the day ... MOST times manufacturers rate their consumption higher to build in a safety margin ... Perhaps someone out there has one of these ... but I will tell you that there is no way that this thing is drawing 16A all day long .. which is GOOD for you ..

 

[Sgt Raven]

So according to the specs the fridge draws 16A at 12V to operate. Now I have no idea if that is 16A constant or just 16A when the compressor kicks on .. I know most of the frdiges we have is 10-20A while the compressor is on and then literally NOTHING when its not --

But either way ... just throwing a 175W (16A) panel up there would not suffice -- since a 175W panel is going to produce at best 160 on a good day and ONLY when the sun is shining directly on it - which is only about 5 hours a day on a yearly avg. So now what do you do about the other 21 hours of non-sunlight ...

SO a couple of ways around that -- YEP add more panels ... also add a DC-2-DC converter that will take power from your alternator while you drive and charge your batteries - to run your fridge ...

BUT the issue is going to be when you are not driving for a couple of days - you will need to rely on the SUN and the Batteries to accomplish this...

BUT I think that 16A number is high ... I will check one of the smaller fridges here at work and see what it actually draws during the day ... MOST times manufacturers rate their consumption higher to build in a safety margin ... Perhaps someone out there has one of these ... but I will tell you that there is no way that this thing is drawing 16A all day long .. which is GOOD for you ..

According to the Energyguide Tag that fridge should use 321kWh a year or 0.88 kWh a day on average. IDK how their lab test relates to real world usage. What would that translate to power needed? Also have to add in the % lost in a inverter, too.

 

[namesgolden]

I've seen people say have 300w of panels and at least 200ah of battery for a fridge and some lighting in most climates.

ofcourse that depends on fridge size/installation+insulation. days of runtime you want vs your needs to run a generator/grid power for other more intensive power demands.

be aware that any motor has a huge start up current draw and is taxing to inverters. you can fight this by:

* running a 24v battery bank with a few parallel cells. this makes it easier to bring up the voltage and draws the power from more than one battery at a time
* installing a "hard start" kit (only a band-aid really)
* buying a fridge with "soft start" (if they exist in that size/price point)

don't go overboard with the inverter because big ones have idle draws that might equate to running a second fridge.

 

[Forbisher]

My main thing is I need a mini fridge. I cannot afford the dometic one that seems popular, so I was going for a cheap dorm style fridge, specifically the Insignia 3.0 cubic ft mini fridge.

I started out looking at Dometic but like you decided that they are too expensive, plastic and not so good reviews.
So i ended up buying an Iceco VL45 at half the price with a metal well insulated box and unbreakage industrial handles plus metal closures.
120 volt plus 24 V or 12V at 7.5 A and runs a bit less than 20 minutes out of an hour.
Since i got my 45l they now make larger fridges.

 

[Dzl]

Hi! I'm so happy I found this forum because I'm pretty much clueless. I'm thinking about long term travel in my van and need some help figuring out how much solar I need. Even with weeks of research I'm still confused!
My main thing is I need a mini fridge. I cannot afford the dometic one that seems popular, so I was going for a cheap dorm style fridge, specifically the Insignia 3.0 cubic ft mini fridge. I see on Best Buy it uses 1.5 amps and 115 volts, which I believe means about 172 watts. Does that mean I can buy a 175 panel and be good to go? or is it not that simple and I need more wattage than that? An article I read says a 3.1 cubic ft mini fridge would need like 400 watts, not 175, so am I missing something or did I just find an energy efficient fridge?

Also, what kind of battery and inverter would I need? On that same article it said 300 amp battery and 2000 inverter. Do you think that's correct or, because I have a more energy efficient fridge, I could go with less? like, I don't know, 200 amp and 1000 inverter?

Any help you could give would be SO appreciated!!!

People may be able to give you specific answers to your many questions. But from your questions, It seems like you are lacking an understanding of the basic fundamentals, before moving on to specific questions, I think you should try to get a grasp of the basic units and math, after that, move on to specific questions (and its likely once you have a command of that basic info, you will be able to answer a lot of your questions yourself, and be a lot more empowered). To start off, watch the first 3 videos in this list. Until you get a basic understanding of the math a lot of the specific advice people would be able to provide you will likely be over your head, at least that's how it was for me.

 

[Ped]

In addition to the above posts I have 8 years experience running a dorm fridge in a van. First of all a dorm fridge doesnt use more than a "dometic." We've done exhaustive tests on this. A dorm fridge uses half the energy of a 12v then combined with inverter draw use about the same. With a 3 cu/ft you should expect to use about 15-25A in winter and 50a +/- 5a in summer. Roughly.

Next the best option is a lifepo4. I have 1 valance I paid $400 and it is a game changer.

The other option is walmart lead acids. Theyre cheaper up front but require so much more energy input and daily care that lower price is quickly eaten up. With lead you can still use 400w of solar but you will need a 2nd charge source. I cannot recommend using vehicles alternator for this. Its just not designed to idle for hours. A generator and charger is best.

I carry a Stanley 25A smart charger. I cut the charge wires and use anderson connectors to give me 2 different ends. One is copper lugs for charging cabin battery and the other is the standard clips in case i need to charge my starting battery. Highly recommend this as its saved me a bunch.

A very small generator can handle the stanley such as the 2 stroke harbor freight things or the dirty hand tools 800w inverter generator.

Either way youre trying to buy a fridge AND design a solar system around that so you have a ton more learnin to do as the previous post said. It seems lile you thought this was going to be cheaper and more simple than you thought.

Bottom line 400w of solar as you have to over build solar to account for clouds. Less solar if you want to run a generator more often.

 

[Ped]

just throwing a 175W (16A) panel up there would not suffice -- since a 175W panel is going to produce at best 160 on a good day

Idk what panels youre all using but 175w flat mounted MIGHT get 9-10A from all my experience. About 5A per 100w.

 

[Rider]

Agree with the above post (DZL's). Check out the Learning and Beginner's sub forums and read up.

That said: I got the 3.5 cf deep chest Insignia freezer from Best Buy. Put an external thermostat on it to regulate between 32 and 36 degrees. It's powered by an AIMS 1000/2000w inverter and a 100Ah AGM battery. Solar power is a single Renogy 270W 24VDC panel fed into a Epever Triron 3210. With that set up, it will run up to 36 hours with absolutely no battery charging, it the battery is being recharged by solar, it will run forever, even on multiple cloudy days.

For Camping

I wanted a small power system for camping, so I used a lot of information gleaned from Will's YouTube vids to put together a system. My main objective was to provide enough power to run a fridge and keep it compact. The Solar Charger: As I was walking thru BJs, I spotted a tiered toolbox that...

diysolarforum.com

There was also another thread I posted in for a recovery effort in the tropics. In that thread I detailed the actual power usage and KWH used by this system.

Found it:

Disaster relief solar for Abaco in the Bahamas. Hurricane Dorian.

In my mind... Can't say I haven't been thinking the same thing. It's one thing to salvage parts, put together a working couple of systems, but the reality is that these systems need to be pretty bullet proof, ruggedized, simple for anyone to use. No way a team of tech geeks is going down just...

diysolarforum.com

 

[Sgt Raven]

Idk what panels youre all using but 175w flat mounted MIGHT get 9-10A from all my experience. About 5A per 100w.

If you're gonna quote someone, then quote what she really said, your quote is without the disclaimer.

" But either way ... just throwing a 175W (16A) panel up there would not suffice -- since a 175W panel is going to produce at best 160 on a good day and ONLY when the sun is shining directly on it - which is only about 5 hours a day on a yearly avg."

the sun shining directly on it, changes the context. Flat mounting is not directly aimed at the sun.

 

[Ped]

If you're gonna quote someone, then quote what she really said, your quote is without the disclaimer.

" But either way ... just throwing a 175W (16A) panel up there would not suffice -- since a 175W panel is going to produce at best 160 on a good day and ONLY when the sun is shining directly on it - which is only about 5 hours a day on a yearly avg."

the sun shining directly on it, changes the context. Flat mounting is not directly aimed at the sun.

Mmm, no. A flat mounted panel still gets direct sun, first off all. And nowhere, tilted or not, have I ever seen any panel produce more than 90% of its rating... IRL.

 

[Sgt Raven]

Mmm, no. A flat mounted panel still gets direct sun, first off all. And nowhere, tilted or not, have I ever seen any panel produce more than 90% of its rating.

Maybe go watch some of Will's videos testing 100W panels in Las Vegas. Right there on camera he had some 100W panels produce over 100% of their rated output. Not all the time, maybe not most the time, but it does happen. Remember the rating is from a certain set of conditions.
Here at 4:15 in this video a cold 100W poly panel with reflectors is producing 122W. That is way more than 90% of it's rating.

 

[Ped]

Were all aware a panel under perfect conditions can produce its rated output or more. But were not talking about that here.

 

[Sgt Raven]

Great. Go put reflectors on a van roof.

That same panel when he first put it out "Cold" was putting out 102W.
Also, you do know that people have tilt brackets for when they're parked, don't you?
I'm going to do this with the panels on my Camper.

One of the YouTube channels I follow, is a 4x4 & camping trailer manufacture in Australia.
They make a hard-shell clam-shell rooftop tent with solar panels on the top.
When parked and set up, it tilts the panels, too. If you face the trailer in the right direction, then you get extra sun on the panels.

 

[Ped]

Sure do. All mine are tilt. It gets me from about 55% to 70% rated output in winter.

But go design your system around 122%. Lets us know how that works out.

 

[Baughb]

Also, what kind of battery and inverter would I need? On that same article it said 300 amp battery and 2000 inverter. Do you think that's correct or, because I have a more energy efficient fridge, I could go with less? like, I don't know, 200 amp and 1000 inverter?

Any help you could give would be SO appreciated!!!

Caroline,

While balking at the cost a Dometic CF or CFX, you are still going to be in shock with the choices of portable power.

I use a "solar generator" (Flexopower 444, 40 amp hours lithium) that charges from my truck or car via a cig lighter cable and then I plug into the unit with my solar panel(s) when I arrive at my destination(s). I don't use inverters as the fridge (CFX50) uses 12v dc or 110 ac. Why convert when I have 12v dc readily available? I have 2, 100 watt Renogy solar panels. One of them is the older, heavy suitcase and the other is a "soft", ultra light weight, foldable. Each on its own, will recharge my 444 in a few hours from about half way down. Together, it recharges quite fast. To be fair, I have not used the 2 panel set up in cloudy or rainy conditions.

This works really well for me. I have used it in excess of 10 days while boondoking at a few of my favorite fishing locales. I have been wanting to build my own portable solar generator with a 100ah LifePo and such but, I can justify the cost as this thing keeps working so well for me. And this is pretty much all that I power. Phones charge mostly on the go in the vehicles and computers are set aside for coffee shops' wifi and power. My iPad is my movie viewing device and it lasts for Days on a single charge.

#1) Will's website has his reviews of portable solar generators of many stripes. Start there.

#2) There are many other manufacturers that have portable fridges that work efficiently on 12v dc and many are reasonably priced. My CFX is rated at 4.8 amps only when it is hot inside, been off for a while, and is trying to get to temperature (36f) with non-cold contents. Most of the rest of the time, it pulls less than 1 amp per hour. So my 40 amp hour battery in the 444 will easily run it for many hours and I am constantly topping the battery off.

#3) The Flexopower 444 has worked excellently for me BUT, not for almost everyone else that I have been in contact with through "overland" board forums. It may even not be available any longer in the USA. I visit Will's reviews often in search for what may be its inevitable replacement.

Hope any of this helps.

Bob

 

[justicelee26]

The Alpicool fridges are really nice and cost less than dometic. They also use much less power than a standard dorm fridge.

 

[Ped]

The Alpicool fridges are really nice and cost less than dometic. They also use much less power than a standard dorm fridge.