2200 watts of solar on the roof?

dreadlocks

Well-known member
Colorado BLM Land just follows these 2 stages, which I believe is what you will commonly find used in the Western US.
Screen Shot 2020-05-14 at 4.19.53 PM.png

Now I suppose every local jurisdiction can add whatever additional restrictions they want, but I dont think anyone gonna give you grief for cooking on a gas stove, I never have been.
 

Peter_n_Margaret

Adventurer
The most I've seen our 900Ah FLA bulk charge is 90A.
Depends on the voltage offered.
I have seen 70A from the 85A alternator going into 400Ah (at 12V) of AGMs, PLUS 30A from the solar 600W of solar at the same time = 100A.
The 70A from the alternator was being offered at 14.4V and drops off fairly quickly at the battery voltage increases. Offering a higher voltage would maintain a higher charge rate.
The solar was being offered at 14.8V and that charge rate (or higher if it was available) will be maintained until the batteries go into float.

Maintaining a higher charge voltage is the purpose of a DC-DC charger, but I am happy to slam a lot more in quickly direct from the alternator and then let the solar top it off.
Of course, the high charge rate from the alternator will be maintained for much longer with LiFeO4 because their internal resistance is lower than LA.
Cheers,
Peter
OKA196 motorhome
 

MTVR

Well-known member
So my big idea, is morphing into something amazingly conventional, except for using high-performance lithium battery(s) in place of flooded-cell golf cart batteries, and an efficient mini-split heat pump in place of a rooftop RV A/C unit.

3,000-watt gasoline-powered generator, modest solar system, 30A shore power connection, propane for cooking and heating water, yada, yada...
 

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rayra

Expedition Leader
Thanks.

The alternator is just a backup when we're parked, although there's no reason not to harness those electrons while we're driving.

We're hoping that our insulation works well enough that we can just shut off the mini-split at sunset...
Lot of the desert southwest in summer it can stay above 100F past midnight, with no real relief before the ball of fire rises again. You better go heavy on the insulation and do whatever you can to shade your vehicle.
 

MTVR

Well-known member
We're planning 3.5" of polyiso, insulated door and windows, and awnings to shade the windows. You think we should go 5.5" of polyiso in the roof?
 

1000arms

Well-known member
I've seen, in the US, fire restrictions banning any flame (even propane stoves) (except for inside an enclosed vehicle) in dispersed-camping non-designated-site situations. The way the bans were worded, one could have cooked outside with a portable induction burner. ...
Colorado BLM Land just follows these 2 stages, which I believe is what you will commonly find used in the Western US.
View attachment 585800

Now I suppose every local jurisdiction can add whatever additional restrictions they want, but I dont think anyone gonna give you grief for cooking on a gas stove, I never have been.
I'm not saying it is common, but I have seen the fire restrictions I mentioned. Usually it is in regard to "dispersed-camping in non-designated-site situations".

I suspect the OP (MTVR) would stick with the legal requirements, which is why I suggested the portable induction burner for any outdoor cooking during certain fire restrictions.

With the wide range of agencies at the city/town/county/state/federal level (and that is just within the US), the possible difference in rules based on location even within a single federal agency, and the low cost of a portable induction burner (if one has the electrical system to power it), I suggest the OP pack a portable induction burner. :)
 

rayra

Expedition Leader
We're planning 3.5" of polyiso, insulated door and windows, and awnings to shade the windows. You think we should go 5.5" of polyiso in the roof?
I would say yes. And it helps in both freezing cold and broiling heat.
But consider awnings, shade fabric, arranging your panel array or even hinging a potion such that it unfolds out beyond the roof edge to shade the sunward side of the vehicle.

Decades ago I had a black 4x4 and regretted it. Several years ago when I began my quest for a used Suburban, I wanted white or some other light shade but after several months I couldn't find the right combination of roadworthiness, disrepair, color combo and price to suit me and wound up buying another black 4x4. Near-instant regret. Too damned hot in the hot tub. So added tint and I added a solid roof deck to block as much sun on the roof as practicable.



Try to rig your panels to provide an air gap underneath them, a breezeway, to aid in keeping the vehicle shelter cooler.
 

MTVR

Well-known member
We've got a height challenge, and we don't want to give tree branches an opportunity to remove our solar panels. The solar panels will probably be mounted directly to the roof with 3M VHB double-sided tape. Thinking of using Panasonic HIT panels, because they reportedly run cooler...
 

Joe917

Explorer
Make sure you have an air gap between yout pane
We've got a height challenge, and we don't want to give tree branches an opportunity to remove our solar panels. The solar panels will probably be mounted directly to the roof with 3M VHB double-sided tape. Thinking of using Panasonic HIT panels, because they reportedly run cooler...
Bad idea. You can't tape those panels on. you need to bolt them to brackets attached to the roof. an air gap is important to help keep temps down, to make habitat more comfortable and to make panel more efficient. Stay with the 3 1/2" roof add 1" air space between panel and roof minimum.
 

Peter_n_Margaret

Adventurer
Solar panels fixed directly to the roof will get hotter and that will cause a reduction of output of about 9%.
But it will also stop the leaves and dirt collecting underneath.
Cheers,
Peter
OKA196 motorhome
 

MTVR

Well-known member
So maybe VHB to hold the brackets to the roof, a 1" gap under the panels, and some kind of nerf bar at the front...
 

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Joe917

Explorer
Our panels are attached (bolts and nylock) to 1 1/2"x 1 1/2" al angle pieces about 6" long, 6 per panel. The angles are bonded to the roof with 3m 5200 (no screws into roof). I have a couple of pieces of stainless bent to guide branches up and over/onto the panels. 5 years no issues. We are not afraid to push our way through branches, no worries.
 

IdaSHO

IDACAMPER
I use use a simple aluminum angle frame and mounts, that allow for quick removal and tilting of the panels.
Ive also drug them under plenty of trees, without issue.

I originally set the panels up to tilt in 4-directions, but never got around to installing the final mounts, so they only tilt left/right and not front/back.
Its easy enough to park it situated in a direction that works well, so its a non-issue. Someday I might get around to the final mounts :unsure:

Our panels are 24V, just two 100 watt units on the roof, and two more that can be deployed on the ground to allow us to
hide in the shade while still soaking up some sun.





 
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