RV power plant installation

WebPower

Here is my system that I’ve recently finished nstalling in our 2011 Sprinter 3500 based 2012 Forest River Coachman Prism 2150 LE.

Renogy DCC-50s 50A battery to battery charger (behind passenger seat base)
Renogy BT-2 Bluetooth transmitter
Renogy communications Hub
Renogy Rover Elite 20A MPPT Solar Charger
Magnum MS2000 Inverter (inside passenger seat base)
Magnum ME-AGS-N Generator Control
Magnum ME-ARC Controller 
Magnum ME-BTS Battery Monitor

4- ECO-WORTHY 195W, ICO-SMC-195W, 18.0 Vmp solar panels
1 - HQST 100W, HQST-100D-SS, 17.9 Vmp solar panel
2 - XS Power XP2000, 80 AH, group 24 AGM batteries- size fits just right width wise.
2 - X2 Power SLI24AGMDPM 76 AH AGM batteries

AdventureWagon auxiliary battery tray

Wood on top of the battery tray holds the batteries in place. The correct dimension golf cart batteries were not available.

I highly recommend the battery to battery charger. Using that and the solar panels keeps the fridge running via 120VAC while we are driving without using propane.

Pat

mike95490

You have 4, AGM batteries wired in parallel ?  of 2 different models ? ( 80A &  76A )?

Wiring AGM in parallel is tricky, getting  the connections right, so the power is shared evenly across all the batteries.
check the site below for good instructions
  http://www.smartgauge.co.uk/batt_con.html 

BB.

What is your solar array configuration and what solar charge controller.

With almost 800 Watt array on a 12 volt battery bank, at least a 40 amp mppt rated controller... If 24 bike, that controller is ok.

Bill

WebPower

The renogy battery to battery charger is also a 650W mppt solar charger. The final install will have 585W on the DCC-50s and 295W on the rover elite. I've just not installed the last 195W panel as I had a roof joint issue that's now fixed. Right now 685W is into the DCC-50s but will be reconfigured shortly. Panels are all in parallel.

Regarding battery balancing i'm kind of stuck with the sprinter auxiliary tray location in the engine compartment and the house install by Forest River that is inside the coach area. So there is a longer run to the main distribution bank from the engine area.  The two in each location are optimally wired. There was really no other place to put more batteries easily. In normal operation we dont pull large loads from the battery bank so i hope the configuration won't be too detrimental to the battery life. The two banks were installed within about 6 months of each other. 
Pat

Alternative

Are you getting good output from the Eco-worthy solar panels?

WebPower

They seem decent but the Renogy app isn't great for history plots. The one panel not installed yet is powering the wind turbine circuit just leaned up against a post at the house. It is in series with another panel so I don't have any good data of the ECO_worthy panels by themselves. I can see what I get on a sunny day with a load on the RV's inverter. Most of the time when I look we are driving down the road and the alternator is also providing power. I do know when I had fuse issues and operating only on solar the 685W of panels wouldn't quite handle the 22A that the fridge was drawing. I'm pretty sure that was during the day, sunny, and in the late spring/early summer. And that said, probably not as good as I'd want them to perform. I do need to pay more attention to what I'm getting out of them. They do keep all the batteries topped up when in storage, but that's a pretty low bar to overcome. But the storage charging is one of the reasons I installed them. Now that you've asked, I'm gonna have to really investigate their performance. So more to come...

Pat

Alternative

I had Eco-worthy flexible panels installed on my van, I noticed that the watts out put kind of low so I though my MPPT charger is acting up, I input all the correct data regarding battery type, capacity and charging methods parameters, after a year they are toast, when I called them they said they don't sell those anymore and tried to sell me another upgraded ones.

WebPower

I've not heard anything good about flexible panels...mine are normal, hard frame, glass, monos. I picked them to match the HQST I already had since they would be installed in parallel so the Vmp's are close. Tried to maximize my installation on top of the RV. That's how I came up with 4-195 and 1-100.

BB.

Pat/Webpower,

Your refrigerator drawing 22 Amps (@ 12 VDC?)... If I got the numbers right, is that an absorption type (ammonia/propane/electric) type?

If it is an absorption fridge... At some point you may want to look at converting to a compressor type refrigerator.

Absorption fridges work pretty well and relatively cheaply (all things considered) when running on propane (1 lb or so of fuel per day). However, if you are full time off grid or trying to live from solar as much as possible, a compressor based fridge uses much less electricity than absorption type (which just use the 12vdc/120vac to provide heat instead of the propane burner). Compressor fridges also tend to be much more tolerant of being a bit out of level better than absorption types).

-Bill

mike95490

My trailer absorption fridge = 4kwh daily

WebPower

I didn't realize the difference between the compressor and absorption. Huge...I try to save propane for heat and hot water. We don't do a lot of off grid but like the thought of not having to worry about draining the batteries without using the generator if I don't plug in. And our RV doesn't have auto leveling, so a thought for the future. That would be another purchase for the RV, reinforcing my wife's money pit ideas of it..

BB.

Compared to Mike's numbers, an efficient DC Powered Compressor Fridge/Freezer would (very roughly) use around 0.5 to 1.0 kWatt*Hours per day (500-1,000 WH/day).

Lots of variability (product, ambient temperatures, fridge only, freezer only, fridge+freeezer, size, etc.) here--But 1/4 the amount of electricity for compressor based fridge is certainly within the realm of possibilities.

-Bill

papab

My DC compressor fridge (NovaKool) is using around 350-500 WH per day.  

WebPower

Those numbers make it soooo tempting to swap the fridge out....I shall resist- for now.