Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×


Reply
 
Thread Tools Display Modes
 
Old 02-21-2018, 08:47 PM   #1
New Member
 
Join Date: Jan 2018
Posts: 7
AC Fridge

We are currently planning on putting an apartment size fridge(10-12 c.f.) in our bus that is 120v, but would like it run off of solar while driving or boondocking. Is this possible? We looking at having a 1000w solar system with 6 batteries.

Harriman is offline   Reply With Quote
Old 02-21-2018, 09:11 PM   #2
Bus Nut
 
superdave's Avatar
 
Join Date: Mar 2015
Location: hills of sw virginia
Posts: 889
Year: 1996
Chassis: thomas
Engine: 8.3 cummins
Rated Cap: 11 window
yes thats plenty of power as long as your not using it on other things. living from solar has a learning curve like most things. design your system so you can add to it if needed.
__________________
living in a bus down by the river.
my build pics
https://www.skoolie.net/forums/membe...albums942.html
superdave is offline   Reply With Quote
Old 02-21-2018, 09:16 PM   #3
Bus Crazy
 
Join Date: Feb 2015
Location: Cincinnati, Ohio
Posts: 1,001
Year: 2000
Coachwork: Blue Bird
Chassis: International
Engine: TE 444
Rated Cap: 12
probably not, the refrigerator will take close to 500 watts when running which it will do about half the time on a normal day. that would be close to 20 amp/hours an hour at 12 volts so you would need 500 amp/hours storage every day just to run the refrigerator at 12 volts. you will need more batteries and solar panels to run it
Kubla is offline   Reply With Quote
Old 02-21-2018, 09:23 PM   #4
Bus Geek
 
Join Date: Sep 2017
Location: Owasso, OK
Posts: 2,627
Year: 1999
Coachwork: Thomas
Chassis: Saf-T-Liner MVP ER
Engine: Cummins 6CTA8.3 Mechanical MD3060
Rated Cap: 46 Coach Seats, 40 foot
Quote:
Originally Posted by Kubla View Post
probably not, the refrigerator will take close to 500 watts when running which it will do about half the time on a normal day. that would be close to 20 amp/hours an hour at 12 volts so you would need 500 amp/hours storage every day just to run the refrigerator at 12 volts. you will need more batteries and solar panels to run it
Actually, a modern fridge of 10 to 12 cu ft will run around 100W on a 30% duty cycle.

That's about 65 Amp hours per 24-hour period. No issue with his proposed system.
__________________
Steve Bracken

Build Thread
Twigg is offline   Reply With Quote
Old 02-22-2018, 10:18 AM   #5
Bus Geek
 
Join Date: May 2016
Location: Eastern WA
Posts: 6,401
Year: 2002
Coachwork: Bluebird
Chassis: All American RE (A3RE)
Engine: Cummins ISC (8.3)
Rated Cap: 72
I put a 10.7cf Whirlpool in my 5er when the absorption fridge died.

No solar yet. I have 2 x GC2 batteries and a 25amp charger that I run from shore power or generator.

It is not ideal for boondocking. I can go 2 days before I hit 50% SOC if I am cautious with other loads.

With 6 GC2s and a well set up 1000 watt solar you should be in decent shape as long as you have adequate sun.
PNW_Steve is offline   Reply With Quote
Old 02-22-2018, 10:37 AM   #6
Bus Geek
 
brokedown's Avatar
 
Join Date: Dec 2016
Location: Weeki Wachee, FL
Posts: 3,056
Year: 1997
Coachwork: Bluebird
Chassis: TC2000 FE
Engine: Cummins 5.9
Rated Cap: 72
If you're using solar and batteries as your primary source of power I'd really push towards a chest freezer setup. Refrigerators that open a door on the side dump your cold air out when you open them, and are less well insulated.
__________________
Keep up with us and our build!
Follow us on Facebook, Instagram, YouTube, and Twitter
brokedown is offline   Reply With Quote
Old 02-22-2018, 02:28 PM   #7
Bus Geek
 
Robin97396's Avatar
 
Join Date: Feb 2016
Location: Willamina, Oregon
Posts: 6,409
Coachwork: 97 Bluebird TC1000 5.9
Quote:
Originally Posted by brokedown View Post
If you're using solar and batteries as your primary source of power I'd really push towards a chest freezer setup. Refrigerators that open a door on the side dump your cold air out when you open them, and are less well insulated.
Chest freezers will also never dump the fridge contents all over the floor when you go around a corner.
__________________
Robin
Nobody's Business
Robin97396 is offline   Reply With Quote
Old 02-22-2018, 03:29 PM   #8
Bus Geek
 
Join Date: May 2016
Location: Eastern WA
Posts: 6,401
Year: 2002
Coachwork: Bluebird
Chassis: All American RE (A3RE)
Engine: Cummins ISC (8.3)
Rated Cap: 72
Quote:
Originally Posted by Robin97396 View Post
Chest freezers will also never dump the fridge contents all over the floor when you go around a corner.
I have seen a few folks do this with the Igloo chest freezers. It appears to be about the most energy efficient setup without going to the high dollar DC refrigerators.

I considered going this route but kitchen layout and convenience won out over efficiency.

I am happy enough with the performance of the 10.7cf in my 5er that I am going to put another in my Bluebird.
PNW_Steve is offline   Reply With Quote
Old 02-22-2018, 03:41 PM   #9
Bus Geek
 
Join Date: Nov 2016
Posts: 2,775
The relative efficiency of chest vs upright is negligible as proven in controlled studies.

The thermal mass of the contents is thousands of times greater than that of the air lost.

And if you need to open the lid and rummage around to find what you need, longer than just opening a door and grabbing it. . .
john61ct is offline   Reply With Quote
Old 02-22-2018, 04:25 PM   #10
Bus Geek
 
Join Date: Sep 2017
Location: Owasso, OK
Posts: 2,627
Year: 1999
Coachwork: Thomas
Chassis: Saf-T-Liner MVP ER
Engine: Cummins 6CTA8.3 Mechanical MD3060
Rated Cap: 46 Coach Seats, 40 foot
Quote:
Originally Posted by john61ct View Post
The relative efficiency of chest vs upright is negligible as proven in controlled studies.

The thermal mass of the contents is thousands of times greater than that of the air lost.

And if you need to open the lid and rummage around to find what you need, longer than just opening a door and grabbing it. . .
Chest fridges will always be a bit more efficient, and you can't argue with those who think that is the main consideration.

Personally, I've used them and for me they are an inconvenient mess.

Understanding that it is perfectly possible to plan even a modest electrical system and have the ability to run a regular domestic fridge means that you can make your own choices.

These choices weren't so readily available even 10 years ago, because the compressors in domestic fridges have leapt forwards in their efficiency.

What you do NOT want is any kind of absorption (RV) fridge. If you have any plans to run it on electricity, be aware that they are about 4X more power-hungry.
__________________
Steve Bracken

Build Thread
Twigg is offline   Reply With Quote
Old 02-23-2018, 08:43 AM   #11
Skoolie
 
bubb, the real one's Avatar
 
Join Date: Dec 2014
Location: central texas
Posts: 170
Year: 1990
Coachwork: Thomas/International
Chassis: 3700
Engine: 7.3
Rated Cap: 72
Remember that one amp Ac equals about 10 amps Dc,
Also remember that you cant pull more than about 10% of a batteries power at any one time without dropping the voltage.
This means that pulling 10amps on a 100ah battery is the max load it can theoretically take, is better to design a system that pulls 5% or less of a batteries capacity.
__________________
my bus thread, https://www.skoolie.net/forums/showthread.php?t=8860&highlight=bubb
bubb, the real one is offline   Reply With Quote
Old 02-23-2018, 12:38 PM   #12
Bus Geek
 
Join Date: Nov 2016
Posts: 2,775
Any fridge pulling over 10A (120+W) is crazy to run off batteries anyway.

Appropriately efficient units might pull 20AH total per 24 hours, maybe 40AH in extreme conditions.

And the vertical door vs chest design has nothing to do with mains-designed vs DC compressor, the objective fact is the former issue has almost nothing to do with energy efficiency, while either of the latter technology choices can be designed either way.

Spending more on fridge efficiency will very directly pay back in allowing for a smaller total electric system, except where fossil fuels are being burned for many hours every day anyway.
john61ct is offline   Reply With Quote
Old 02-23-2018, 02:06 PM   #13
Bus Geek
 
Robin97396's Avatar
 
Join Date: Feb 2016
Location: Willamina, Oregon
Posts: 6,409
Coachwork: 97 Bluebird TC1000 5.9
I chose the freezerator for several reasons;

1. It doesn’t block my view
2. The contents won’t eject all over the floor if the latch fails
3. These are reasonably efficient.
4. Most importantly, my kegs will fit in this freezerator.

I don’t expect to run this freezerator the majority of the time. It is simply a way of preserving food when opportunities arise. As in the unlikely event I should ever get good at fishing or something, you know?
Most of the time this will be a dry storage box with a countertop over it.
__________________
Robin
Nobody's Business
Robin97396 is offline   Reply With Quote
Old 02-23-2018, 05:57 PM   #14
Bus Geek
 
Join Date: May 2016
Location: Eastern WA
Posts: 6,401
Year: 2002
Coachwork: Bluebird
Chassis: All American RE (A3RE)
Engine: Cummins ISC (8.3)
Rated Cap: 72
When looking at loads run off of the inverter:

Watts out/efficiency = watts in

Example:

I have a fridge that consumes 120watts when the compressor is running.

My inverter is 87% efficient. So.. 120watts out / .87 = 138 Watts in.

So, I have to feed my inverter 138 watts to support the 120 watt load.

To figure battery current draw we use I=P/V or Current = power/voltage.

I have a 138 watt load and a 24volt battery. 138watts/24volts=5.75 amps.

Clear as Mud?
PNW_Steve is offline   Reply With Quote
Old 02-23-2018, 07:08 PM   #15
Bus Nut
 
Alan N's Avatar
 
Join Date: Jan 2015
Location: Gonvick MN
Posts: 339
Year: 1975
Chassis: Gillig
Engine: Cat 3208t/10 speed transmission
I don't know about the watts or amps but I have a 10 cubic foot house fridge that we run off an inverter.
I have 3 group 31 deep cycle batteries. We can usually go three days or so before the inverter starts complaining about low voltage. I often turn the inverter off at night. No solar panels yet but they are on the to do list. I am sure that I am doing everything wrong but my ice cream is always cold. This has worked for us the last ten years.
It will work for you.
Go for it.
__________________
Remove hence to yonder place....
Alan N is offline   Reply With Quote
Old 02-23-2018, 07:13 PM   #16
Bus Geek
 
brokedown's Avatar
 
Join Date: Dec 2016
Location: Weeki Wachee, FL
Posts: 3,056
Year: 1997
Coachwork: Bluebird
Chassis: TC2000 FE
Engine: Cummins 5.9
Rated Cap: 72
We are on a mostly liquid diet so our refrigerator has a relatively easy job. Just keep drinks cold enough to drink. We can run it about an hour per day and we have occasionally not run it for a long as a week when the sun didn't cooperate. Using the chest freezer has been great.

Sent from my Nexus 6P using Tapatalk
__________________
Keep up with us and our build!
Follow us on Facebook, Instagram, YouTube, and Twitter
brokedown is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 06:01 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.