Battery power consumption

[DackX]

Hi friends
Looking for guidance. Considering an Iceco LV45ProS cooler and wondering about battery capacity and consumption. I am new to this.
I have a 100AH AGM Battery running through a RedArc Manager 30 with 180 watt solar.
I use a CPAP machine during the night which typically consumes about 15% of my battery. Knowing I cannot deplete an AGM battery below 50%, I am wondering if the cooler running all day plus the CPAP and periodic use of my LED interior lights will deplete my battery in a 24hr period. Obviously I would do whatever I needed to recharge during the day through solar, alternator or generator.

The IceCo claims 0.715 kw.h/24h

Thank
Dack

 

[Tesota Overland]

Convert the units and it's easier to compare:

0.714 kWh * 1000 = 714Wh / 12V = 59.6Ah

Website actually lists a different value but doesn't say what temp the fridge was set to or what the ambient temp. If we re-run those numbers here's what we get:

0.509 kWh * 1000 = 509Wh / 12V = 42.4Ah

These numbers sound about right to me for a fridge that size for a 24h period, unfortunately it does put you pretty close to the limit for your current batteries though if they're AGM.

Manager30 is a great choice btw.

 

[jonyjoe101]

I had a 43 qt edgestar and currently have a 26 liter joytutu 12 volt fridge, when set to about 40 degrees F, they both comsumed about 20ah's / 24 hour. I measured the usage with a DC wattmeter.
As long as you got good sunshine you can run the fridge indefinitely with solar and a 100ah battery. I use to run my edgestar 43 qt with a 120 watt panel and a 75ah agm for years. During the day the fridge runs off the solar so everyday you mostly have to account for the night time battery use.
Just make sure the battery is getting fully charge everyday by measuring the voltage at the battery terminals, the terminals need to reach at least 14.4 volts and stay there for hours. Solar charge controls are notorious for undercharging lead acid. Don't let the battery terminals get below 12.1 volts.

 

[Peter_n_Margaret]

Knowing I cannot deplete an AGM battery below 50%

That is an urban myth.
If the solar is producing more than the loads, it is the solar powering the fridge etc during the day, not the battery. The battery will be charging all day and should be fully charged but late afternoon at the worst. That means the battery only has to supply the loads for the fridge etc when the sun is not shining.
Cheers,
Peter
OKA196 motorhome

 

[rruff]

The IceCo claims 0.715 kw.h/24h

The website says 509 wh per day. That's a high number... and I doubt typical since that is a quality fridge. Half that is more like it, like the two posters above ^.

On an average day you should harvest ~900 Whr of solar energy, but you can't count on the sun shining. It would be a good idea to measure what your CPAP consumes in a typical night; they can vary a lot in energy consumption. I have a Kill a Watt for measuring AC loads; there are a lot of similar devices.

 

[DackX]

Convert the units and it's easier to compare:

0.714 kWh * 1000 = 714Wh / 12V = 59.6Ah

Website actually lists a different value but doesn't say what temp the fridge was set to or what the ambient temp. If we re-run those numbers here's what we get:

0.509 kWh * 1000 = 509Wh / 12V = 42.4Ah

These numbers sound about right to me for a fridge that size for a 24h period, unfortunately it does put you pretty close to the limit for your current batteries though if they're AGM.

Manager30 is a great choice btw.

Thanks.. this is very informative and exactly what i was looking for. IceCo mentions that the values were based on Max power at 0 degrees F.
So if my CPAP is normally utilizing say 15 % of my 100AH and the cooler will use say 40-60 %/24 hr period, if the sun isnt shining i will deplete below 50%.