Fridge Power Draw

[Zam15]

Ok,

I recently installed a 60 watt solar panel and would appreciate any input.

Solar Spec:
60 Watts, 4 Amps, 15 Volts Out Per Hour
Average 7 Hours of Daylight - 28 Amps Per Day

Fridge Spec: (ARB Ref)
.7 to 2.3 Amps Per Hour
16.8 to 55.2 Amps Required Per Day


I am looking to have my solar setup negate the power used by a fridge. Basically operating the fridge 24/7 without the need for an outside power source. Max power draw from the firdge for this to work is 1.1Amp Hr?

If power use falls into the .7Amp/Hr range I will have more than enough power.
If it falls under the 2.3 range the battery will start to deplete. (5 Days on a 130Amp Hour Battery)

Sunny Day: Fridge has to work harder but more solar energy is available.
Cloudy Day: Fridge does not have to work as hard and normally less solar is available.

So my two questions are:

What are the best fridges on the market in terms of power use?

If you have a fridge what kind of average draw are you getting?

Thanks!

 

[Pest]

Hot Day: Fridge has to work harder but more solar energy is available.
Cold Day: Fridge does not have to work as hard and normally less solar is available

I can't answer your question, but I don't follow your assumption that a cold day means less solar power is available, unless where you love cold always means cloudy. Generally, a cold and sunny day (which is common in Colorado at least) is the best conditions for solar. Panels are more efficient when colder.

 

[cnynrat]

The Summer 2010 issue of Overland Journal had a very extensive test of a number of the popular fridges. I know they did a couple of current draw tests. I think one was a cool down test, and the other more of a steady state keeping things cold test. I don't have it in front of me right now, but IIRC the new style ARB fridge did pretty well in those tests.

 

[Zam15]

I can't answer your question, but I don't follow your assumption that a cold day means less solar power is available, unless where you love cold always means cloudy. Generally, a cold and sunny day (which is common in Colorado at least) is the best conditions for solar. Panels are more efficient when colder.

Sorry, I meant cloudy vs sunny. Normay that goes hand and hand with cold and hot here is San Diego.

The Summer 2010 issue of Overland Journal had a very extensive test of a number of the popular fridges. I know they did a couple of current draw tests. I think one was a cool down test, and the other more of a steady state keeping things cold test. I don't have it in front of me right now, but IIRC the new style ARB fridge did pretty well in those tests.

I have been mainly considering the ARB but if there is a better alternative I would not hesitate in changing my mind.

 

[Mike S]

A couple of points...

The fridge will not be running 24 X7 - it will cycle on and off depending a lot on insulation and ambient temp. My fridge doesn't anywhere near 3 amps/hour - probably less than 1/2 that when running, and it isn't running much of the time.

A thermal jacket is a very good idea to reduce electricity usage.

I turn my fridge (Engel 45) off at night - even in warm weather it stays very cool through the night with the jacket.

 

[orangeTJ]

I bought one of these for my ARB Fridge.... it's foil insulated on the inside surface.

It does have a thin layer of insulation in it too. I bought it at the same time I bought the fridge - got them both from Northridge4x4.com in WA state

http://www.northridge4x4.com/proddetail.php?prod=ARB-10900013

 

[Martyn]

We ran long terms test (60+ days) on the Engel 45 and measured the power drawer using a Doc Wattson. The official power consumption on the unit is 0.7 - 2.5 Amps. Our average power consumption over 60 days of 24 hour usage was 1.2 amps per hour.

The official power consumption goes from the high reading when the compressor first kicks in, or surges, to the lowest level when the compressor is running at it's most efficient.

The power draw over a 24 hour period will depend on what temperature the fridge is set at, any extra thermal layers or jackets, the air temperature, if the fridge is in direct sun or not, and how well the fridge is packed.

You have control over the thermal blanket, if it's in direct sun or not, the fridge temperature setting and how well the fridge is packed. Pack the fridge as full as possible and keep it that way as long as you can.

Your solar panel will put out on average, full power for 8 hours and a few hours in the morning and evening when the sun is at low angles. I figure it will put out 28 amps in a 12 hour period.

The Engel fridge will consume 28.8 amps in 24 hours so it almost balances out.

 

[Corey]

Here is my installation, and I have a 60 watt panel to keep the starting battery (where the fridge is hooked up to) charged up.
60 watts is plenty to do what you want.
http://expeditionportal.com/forum/showthread.php?t=28712

I use the ARB 1st gen fridge which draws around 1.7 amps or so.

I like Mike's idea about turning it off for the night, something I have not tried yet.
I have the T-Bag for my fridge, but have never used it.
I do not think it would work now since I modded my lid as seen by the link in my sig.

 

[Zam15]

Thanks for the tips, I am sure they will save me a few watts

 

[LandCruiserPhil]

You want to also factor in a full frig is much more efficient then an empty one and the amount you open it and leave it open also add to more power consumption.

 

[wrcsixeight]

I've got a Norcold DE 0040 front loading fridge that I bought in June 07.
It has been running 11 months a year ever since.

When new, it consumed 2.7 amps when the compressor was running.

It now consumes just over 2.4 amps.

It runs about 20 minutes per hour at 70 degs f.

I have added extra insulation to the case, and an internal 25mm fan and an external 40 mm fan that run 24/7. They more than make up for the .15 amps they consume. It is located in a noise and temperature insulated cabinet which promotes airflow over the cooling fins and compressor.

My 130 watt panel makes more than enough to power the fridge here in coastal San Diego. I have not tilted it in 6 months.

I have methods to keep my Van's interior temperature cooler, but the extra length of the day and angle of sun in the summer allows me to use significantly more electricity overnight and have the batteries full by 2 pm the next sunny day.

Sometimes when the batteries reach 100%, I will turn up the fridge(colder) until sundown so as to try and use the extra electrons the panel is making by storing them in colder fridge contents.

I have tried turning it off overnight for 6 to 8 hours, and the next morning when I turn it on, the temp of everything has risen to about 46 from 38F, and the duty cycle increases to about 66% that first hour, and it takes about 5 hours for it to go back to the 33% dutycycle with the contents at or below 38f, but this hourly figure is dependent on how much I have in there at the time.

I have not sat there with a stopwatch, but it is my opinion that turning it off at night probably uses more electricity to get the contents back below the 40 degree threshold when turned back on. I'd rather my food stay below 40 degrees the entire time.

I have an amp hour counting battery monitor I look at often.

The fridge's compressor is noisier than I would like.

 

[orangeTJ]

I have an amp hour counting battery monitor I look at often.

I have one too, and I could easily do some data logging with my ARB, if I found the time to do it.

At a minimum I could at least get an idea of how frequently it runs.

 

[NOMAD X]

New... Help needed

Hi, My name is Frank. Owner of a 2008 Ford Explorer. I recently bought an edgestar 43qt for outdoor camping.
I have a red top as main and yellow top for aux power. However i don't know how to read all its specs and how they pertain to drawing power from freezer.
Crank Amps 870. Res cap 120 amps hours 55.

My questions are: how long could i run my freezer without charging battery?
How much solar power amps do i need to run it 24/7?

Thanks for all the help.

Frank

 

[Jeff Wanamog]

What will also make a difference is what charge controller you use. If you spend a little more money for a MPPT controller, it will convert the additional voltage into charge amps.

Jeff

 

[Zam15]

Hey-O! 11 Years later upgrading my solar on my newish to me camper to a proper solar setup. Fridge still going!

New controller, circuit breaker and two 100w (tested @ 11 Amps, 20v, so 200-220w in full sun.

Flexible panels going on the roof of the Flip-Pac! Yes will only work with camper closed, but camper is really only open at night so yea.