Residential Solar Panel on RV

[millsrv]

Please forgive me if this has already been discussed, I did not find anything on it here.
I am about to install a residential 60 Cell LG Monocrystalline 280 watt 36 volt panel on my Winnebago Voyage. It seems that no one is doing this, perhaps roof space is the big problem, my Winnebago contains the AC in the basement so I have room.
Using a MPPT Solar Controller / Battery charger this panel should work fine. The higher DC voltage generated by the panel will be reduced and the amperage stepped up to charge my 12 volt battery bank. (I have added two 6 volt golf cart batteries to the existing two for a total of four).
I found the panel new for $100 and cannot pass it up. In addition smaller gauge wire can be used as the panel voltage is higher so voltage drop from the panel to the controller is not as big of an issue.
I would appreciate any input about this project and If there is something I have not considered please let me know.
Thank you!

[TQ60]

No clue here to ecstasy how it works but something to confirm.

The higher voltage indicates less amps for same wattage so smaller wire would be okay..that is easy.

But converting from 36 to 12 could be done in multiple ways either by dc to dc conversion to simple controlled resistance depending on how the controller works.

Look at controller losses before purchasing one.

Have done some design work for battery plants with multiple output voltages and conversion factor can be wasteful of energy.

We used panels rated for dc plant system voltage to avoid most conversion losses.

There are some here with more history with such things and contacting the manufacturers of the controllers can also be helpful as they can help to select most efficient unit.

[vsheetz]

Sure, is now common for folks to be installing high voltage residential type PV panels on RV. If they have the physical room to do so. And some are even placing them high and over equipment on the roof using racking systems. The benefits are as you outline. A search here will find much info and details of many existing projects. Good luck.

[drdarrin]

I have two 260 watt residential panels on the roof of my 5er, connected in parallel to a 45A MPPT controller. Works just fine.

My wife and I have been out 3 weeks now and have had to use shore power once, in the forests of Oregon.

[millsrv]

Here is a link to the MPPT controller I intend to use;

http://www.solarproductswarehouse.com/inventory/268057/

[drdarrin]

Never heard of it and unless it's configurable to charge the batteries you have or intend to use, temperature compensated, I wouldn't consider it. I went with the Morningstar controller based on much research and reading dozens of blogs and articles on solar.

[twinboat]

I have 3, 225 watt, 36 volt residental panels, series wired, to a TS MPPT 60 amp controller.

In service since 2011 on a salt water, cruising boat. No problems so far.

[millsrv]

Originally Posted by drdarrin

Never heard of it and unless it's configurable to charge the batteries you have or intend to use, temperature compensated, I wouldn't consider it. I went with the Morningstar controller based on much research and reading dozens of blogs and articles on solar.

It is both, the battery temp probe cost $11 additional. See the link I posted.

[PJStough]

Originally Posted by drdarrin

Never heard of it and unless it's configurable to charge the batteries you have or intend to use, temperature compensated, I wouldn't consider it. I went with the Morningstar controller based on much research and reading dozens of blogs and articles on solar.

And just because it has a setting for your type of batteries doesnt mean that setting is the optimum setting for your type of battery. If the settings within the battery type are not adjustable, then it is not a very good controller in my opinion.

[drdarrin]

Originally Posted by millsrv

It is both, the battery temp probe cost $11 additional. See the link I posted.

I understand the desire to save money, I did my own install for that reason. I'm in Sacramento if you'd like to drop by and see what I did.

[vsheetz]

I recommend a quality controller such as from Morningstar.