Will this do the job on a sunny day?

IMHO you will be a bit marginal.
It will depend on the duty cycle of the fridge and how many amps it actually draws. If it is 4.5 amps with the fridge running, if the duty cycle is 50% then you will use 2.25X24 = 54amp hours per day.
a 100 watt panel will not give 100watts through a PWM regulator, but an MPPT will give more.
However , say you get 5amps for 4 hours ( my 120watt gives 6amps at 1PM)and 2 amps average for 3 hours, that is 26 amp hours total per day generated.

Your battery will give about 50% of its capacity without damage so it will give 60amp hours roughly.

So the fridge should run about 2 days at 50% duty cycle before the battery is effectively flat. That assumes 50% duty cycle and in hot weather this is not certain or even likely.

That is a big fridge so needs a lot of power.
Regards Philip A

Hi Cathy,

The above configuration will not be enough to power your fridge. If the fridge draws an average of 4.5amps/hour then it will draw up to 108 Amps in 24 hours (4.5amps *24hours = 108Amps). Your solar panels will produce 100watts/hour which is 8.33Amps/hour. In 8 hours it will produce a total of 66.67Amps so you will be short 41.33Amps/day which will be drawn from the battery. Your 115Amp battery, which should only be discharged to 50% (57.5Amps) to get a decent life, will therefore only provide this shortfall for just over a day.

For your set up you need at least 200Watts of solar panels to stand a chance of it being sufficient. Remember, not all days are sunny and cloud cover will reduce your ability to produce power. Also, you may be able to lower the load the fridge draws by keeping it out of the heat (shade, good ventilation and insulated cover) to get by.
Regards,
Sn00py2

Cathy

Not sure if this suggestion is useful or practical in your situation.
I don't have a solar setup but am currently (if you'll excuse the pun) working on one. What we do is let the fridge run for about an hour after the last food or drink is taken out, usually at night, and then either shut it off or at least turn it right down depending on the ambient temperature and turn it back on the next morning. It seems to help conserve the battery a bit and depends on when the car is next started.

Cheers
Pop

Cathy,

Can't help you with any info on the Waeco, but can offer some advice on your solar panel.

Unless you are prepared to "track" the sun with your panel, you won't get 8 hours of peak sun. Would suggest peak hours with a stationery panel would be more like 4 hrs. We've got panels on the shed, and it is at least 10am before approaching peak watts, and then by 2 or 3pm, it's already falling towards 50% output. Was amazed, and disappointed, at the effect the different angles of the sun, affect the output. An MPPT regulator would boost things along a bit better for you.

We are in Central Qld too, so get plenty of sunshine. Also, a number of people on this site have bought panels from Bit Deals. They're panels are pretty good value, and the service has been good too. No affiliation etc.

Bob.

We have a new model Waeco CF80 which I believe uses the same compressor as the CF110. When I bought the fridge I ran a number of tests to find out just how much power the fridge would use (to compare to the 2 older fridges that we had previously used). I found that the fridge draws approx 4.5 amps when running (starts at 6 amps and drops to 4.5 for most of the on-time) and ran at about a 50% duty cycle with an ambient temperature of 18 degrees and configured as one cabinet, ie dividers removed and keeping a couple of bags of ice frozen.

In practical use we have approx 250AH of battery and can run without external power for 2-3 days in Queensland in the winter months when using the fridge as a combined fridge/freezer.

We also have an 80watt panel which I drag out if we are confining ourselves to the campground for a longer period and get a peak output of 5 amps when it is cool, but in normal use it will provide closer to 4-4.5 amps provided I keep it aimed at the sun. In summer the output drops to 3.5-4 amps. We get around 25 AH per day from the panel in winter like this.

In your case your CF110 fridge will draw more power than our CF80 and you have less battery and are not planning on being 'tied' to your campsite to move the 100W panel around. You need a much bigger solar setup, or a generator to satisfy your requirements.