Adventure RV solar setup for running AC and fridge off-grid

[EdH_]

We will be stopping at Adventure RV to get either a 12V conversion or a DutchAire fridge. Also, we want to be able to boondock from time to time for a day and run the fridge while travelling 6-8 hours, so we are getting solar installed as well. Aaron @ Adventure RV suggested the following, given our request:

- 14-2702 Victron MultiPlus-II 12/3000/120-50 2x120V..Inverter/Charger
-Victron Energy Lynx Distributor
SmartSolar MPPT 150/60-Tr ..Solar Charge Controller..Victron Energy
-8 200W solar panels (1600W total)
-2 Voltech Smart 314 Ah 12v batteries (he called them their own batteries; they are not heated, but we don't think we'll be boondocking below 40deg))
-Victron Energy Bus Smart Dongle (Bluetooth)
Note: He said no DC-to-DC charger would be needed while driving; the solar would provide enough.
(I must say, compared to ABC Upfitters, the price is much more reasonable. We'll be able to get all this *and* the fridge for about the cost of just 400W of solar.)

Given the above recommended setup and requirements:
-Does this seem adequate/appropriate?
-I know at least one person has had solar put in by Adventure RV. Can anyone else speak to their experience?

Thanks a bunch!
Ed

 

[LeftOverParts]

Re the solar system, is it designed or intended to run one or both ACs for the one day (or few days) of boondocking?

 

[EdH_]

The requirement was to run 1 A/C & the 12V fridge for 6-8 hours.
We have a 2018 3950BR. The bedroom is a Dometic Penguin, and the family room is a Dometic Brisk, I believe.

 

[nickens]

I would max-out the PV, you should be able to get at least 2400W. DCDC is worth if travelling every 1-2 days. the biggest DCDCs I've seen are up to 60A, or about 750Wh at cruise so every 2 hours of driving will replace 1 hour of your estimated 120v draws which helps on cloudy days. If you only drive every 3 or more days a small generator might be a better choice over DCDC.

Given the poor history of A/C performance and our poor insulation, your A/C will be 100% duty cycle with ambient temperatures above 80F. Figure at least 1000-1200Wh, add another 100-200Wh for the fridge, plus other draws and parasitics (inverter -9%), and you will need every electron out of those. Next you have to factor-in that panels only produce a modest percentage of their rated power due to efficiency, average angle of the sun, and other gee-whiz stuff: most pundits say count on 50% of the rated power over the course of the day.

YMMV

 

[nickens]

Neglected to factor in the batteries...
With 6.4Kwh of usable battery capacity, your batteries would be down to the recommended minimum 20% in 4-5 hours, so 1600W (800-1000W net) of solar would get you through the day, but you would need shorepower or a genny to get you through the night.

 

[EdH_]

I would max-out the PV, you should be able to get at least 2400W.

Sorry..."PV"?
And thanks for your input, btw!

 

[nickens]

Sorry..."PV"?
And thanks for your input, btw!

photo voltaic - solar panels

 

[LeftOverParts]

It would be interesting if they were willing to share their assumptions and calculations. (I’m no pro but seems they have designed a 5 hr system assuming you will need about 7500 watt hrs for 5 hrs of run time and you have 5 hrs of peak sun). Maybe at least get clarification (in writing) that they are confident that it will be an x hr system if you get 5 hrs of peak sun, running the AC and refer the entire time. Sometimes, the designer and what you told the sales guy you want could be two different things.

If not already installed or included in the project, I would want an AC soft start.

+1 for considering a DCDC charger and a generator for those cloudy/overcast days.

 

[Daryles]

1. Gotta have a SoftStartRV on the AC unit you want to run.
2. What brand are the Solar panels? I bought 200W Rich Solar panels years ago. I believe they now have 250w panels with the same foot print. Maximize your solar. They do NOT put out the advertised wattage.
3. If putting your batteries in the battery compartment, insulate it first. You can add battery heaters. Lithium battery heater using tank heater pads
4. DC-DC charger, good for a backup and rainy travel days DC to DC charger
5. I thought the Victron Multiplus was an All in one, converter/inverter??? If not the 3000W inverter is a good idea. Double check this.....
6. Add a Battery shunt. Victron BMV-712 if the Muliplus doesn't already have that function.
7. Insist on a copy of the wiring diagram and layout for future troubleshooting.
8. And after all that you still need a generator for backup. We have 1200w of solar, 512Ahs of batteries, 3000W inverter wired into an ATS wired directly to the circuit breaker panel. We can run anything, just NOT at the same time. Power management is KEY.
We carry 2 Harbor Freight 2000w predator generators and a parallel kit to run things when the solar and batteries cant keep up (rainy days, overcast skys). We were in Canada at their provincial parks. Lots of TALL shady pine trees. No solar. Generator hours 7-8am , 5-7pm. Strictly enforced. DC-DC charger came in handy. In places we had sun the solar and lithium batteries worked flawlessly!!!!
Lithium batteries charge FAST!!!!!

 

[jkxtreme]

I don't think you have enough battery power there

 

[Ron_Z]

I'm not sure soft starts are required with the Victron. I don't plan on using them on my new AC units. Victron Multiplus II has load support that will cover the compressor start up surge. I would not be surprised if JC has not factored that in. I also always advocate the most solar and batteries possible. Your solar will never preform to rated capacity due to angle of the sun/cloud cover/trees etc. that said I swear by my solar (1400W) and battery (600AH) set up..Plann on increasing batteries soon. I find a small gen can cover the gaps in poor weather and tree cover. I would be concerned with AC run time on batteries and solar only. I am in the process of dumping a failed magnum inverter and have ordered the new Victron MultiPlus-II 12/4k/160-50 2x120V. and installing new Houghton AC units which use less power. I don't have a DC to DC charger installed and still not sure it would be beneficial since my solar does a great job of keeping the batteries topped off.

 

[scottz]

I have a similar system; Victron Quatro II (same as MultiPlus but with extra AC input for my on board Onan generator), eight 215W panels, 920AH batteries. My batteries will support running a single AC for about 5 hours before I get nervous; any solar output would extend it a little. Sounds like a good system but light on the batteries. Max out the solar that your footprint can support; solar panels are inexpensive. Take a close look at the batteries; I would be skeptical of "their own batteries". Do some research before pulling the trigger on batteries; I have been happy with Epoch. Batteries are expensive, but cost is coming down. In any case, you need more battery power. As Daryles said, you will also need a shunt and battery monitor (I have a BMV 712). Soft starts would also be a good idea. DC-DC converters can be added later if you find you need them. Write up on my system

 

[Carle3]

That 3000va at about 2600watts will run your air but if you kick in the microwave and have any other draw going it may well overload the inverter. You may want to have dual inverters running in
parallel to avoid having any limitations while off grid. Just got done installing 2 24/3000 2x120’s and I’ve been able to run both of my Air Conditioners, coffee pot and the microwave without an overload. I do have soft starts on my Coleman Mach’s

 

[Kfinnert]

There is a lot of discussion and a bunch of good advice. I highly recommend DC to DC and soft starts for ACs - I have both! My thoughts are based on good and bad experiences when we have been boondocking and using my solar system.

DC to DC: There will be cloudy days, some locations will not let you run the generator to charge batteries however they never fuss about the truck idling to charge the batteries, and you will find that you will run down the batteries driving down the road with the AC (Just One) on. Another nice thing we have found is that with DC to DC, we can have an AC and the crockpot going so we have a cooled down rig and dinner ready when we get in. For the price, DC to DC is worth the price.

Soft Starts: Also, I would have soft starts put in for my ACs. I have two, and we can run two on solar using the soft starts. The start-up is the biggest draw, and with the soft starts is lessens the start-up load and avoids an error or shutdown of the system when on solar. Running two ACs will drain the battery quicker, but with the on-board generator, or DC to DC running, we notice no difference between solar and shore power.