Adding Solar to 21RBS

[nhlakes]

Considering adding solar to my 21RBS.  Had one small panel years ago on my A-liner.

For those of you that pay more attention than I have to solar setups in recent years, what's the biggest bang for the buck these days.  I have a couple of costco 6 volt gc batteries.

Project is more for fun than need, which is why I'm looking for the best price point.   I have a pair of Hondas if/when needed, but prefer not to use them unless necessary.  I'm also on the east coast, so not in the wide open space out west where solar is much better.  Often under trees.

Probably go fixed mount - even though I know a moveable panel would allow me to chase the sun.  This way I can just leave it on while in parked and it will keep the batteries charged. 

PWM vs MPPT controller?  MPPT is more expensive but better.  Again, best bang for the buck?

Renogy still one of the go to brands?

[DavidM]

I do like the Renogy brand. They sell more and more sophisticated electronics as well as basic solar panels for the RV and boating market. But I really like the Victron MPPT controllers.

If you camp in the shade often, do consider portable flexible panels. A single 160 watt Renogy costs only a few hundred $ and it weighs less than 10 lbs.

Use it with a 50' cable so you can move the panels around.

I wrote an article on solar for the Newsletter a while back. Merlin has a portable system that serves him well.

David

[Merlin]

Solar panels are VERY much affected by shade. I strongly echo what David wrote and think that a portable panel is the way to go. If I was to do it over again, I would do the same thing I did before. 100 watt Renogy portable flexible panel (not the heavy suitcase style) running through 40' of wire to an MPPT controller in my battery box and then through a circuit breaker to the batteries. Victron equipment is top-shelf stuff, but I used a Morningstar controller because I had one from another project I could use. Even if the project is for fun (most are!), you'll have more fun (read satisfaction) with a portable panel and with an MPPT controller.

This is a huge growth area right now in RVs. Everybody is doing solar, both RV owners and aftermarket manufacturers. All the big names like Xantrex and Renogy, etc. are producing panels and systems for RVs. I'm a big advocate of KISS (keep it simple stupid) but quality equipment is worth it even in a simple system. Just watch the cost because there are too many folks out there willing to pay silly high per watt prices for solar (Zamp for example). For flexible panels, I would not pay much more than $1.50 or so per watt (maybe up to $1.75). Another thing to consider is to purchase a charge controller with adjustable output and/or presets for both the batteries you have now and LiFePO4 batteries. When you get ready to replace those GC2 6V some day, it's very likely you'll want lithium. Almost all Victron MPPT controllers can be preset for a variety of battery types.

Keep us posted on the solar adventure. It's fun to see what others come up with.

[nhlakes]

Thanks for the replies.

Priority is: 1. Interesting Project, 2. Charge in driveway, 3. Charge at campsite.

I totally get that portable will help me charge much better while camping, but I don't want to leave a portable setup out in my driveway all year (where the camper is parked 95% of the time). 

I'm leaning toward installing a panel or 2 on the roof and then later add a portable when needed.

I'm a fan of Victron as well.  I have a  Victron BMV 712(think that is the model #) with blue tooth dongle already installed.  I'd plan to look into seeing if using a Victron controller with the BMV would provide me with any additional functionality.  But Victron stuff is on the pricey side.

I do recall Dave's write up and did read it when written.  Thanks for the reminder, I'll give it another peak to refresh my memory.

My brother in law and his wife boondock all winter on BLM land AZ in their 5th wheel.  He has 8 180 watt manually tilt-able panels and 6  battleborns, controllers, inverter, all professionally installed. What a setup.

[nhlakes]

You guys are risking making my project too easy.  I just looked at the Renogy flexible panels and it appears I could probably just velcro (hd) them in place while the rig is parked in my driveway and they would probably stay put, not be too obtrusive, and not say say 'come steal me'.  hmmmm

[DavidM]

You guys are risking making my project too easy.  I just looked at the Renogy flexible panels and it appears I could probably just velcro (hd) them in place while the rig is parked in my driveway and they would probably stay put, not be too obtrusive, and not say say 'come steal me'.  hmmmm

If the panels can be easily removed if velcroed on top of your camper, then disconnects like the SAE (ZAMP) or the MC4 connectors and then use a long cable to place them in the sun when necessary. But for velcro to work you would have to have a tight leading edge to keep the wind from working under it and blowing it off.

David

[nhlakes]

Understood, but in case it was not clear, the (industrial type) velcro (plastic/plastic) would just be used while parked. 

Still toying with 100wts installed up top and then another 100wts flexible for when I'm really trying charge.

For those that have installed up top, would love to know how you ran the wires.

[Merlin]

Or get one of these and use your velcro idea for stationary use and also be able to move it around when camping. 

This would need at least a 15A charge controller.

https://www.amazon.com/Renogy-175-Watt-Volt-Monocrystalline/dp/B082FCZ4MD/ref=sr_1_3?crid=33P0L75HOYZ55&dchild=1&keywords=renogy+175w+flexible+solar+panel&qid=1602962719&sprefix=renogy+175%2Caps%2C162&sr=8-3

[nhlakes]

In addition to pricey - it's a big sucker: Dimensions: 59.2 x 26.5 x 0.08 in

[Merlin]

In addition to pricey - it's a big sucker: Dimensions: 59.2 x 26.5 x 0.08 in

Huge!

Anyway, I found the perfect solar panels. What could go wrong with a name like this?

https://www.solar-electric.com/lib/wind-sun/Merlin_FXT_series_specifications.pdf

[nhlakes]

Thinking of going with the 100wt Renogy flexible for now and the HQST 20amp waterproof controller and mounting it at the battery box.  May lose some efficiency with the larger than necessary  controller but want the ability to add another 100wts down the road.  (and had to bump to 20amps to get a waterproof controller from a major well-rated brand).

Have not looked into connections/wires yet.

Comments welcome.

https://www.amazon.com/dp/B07BMNGVV3
https://www.amazon.com/HQST-Voyager-Waterproof-Postive-Controller/dp/B086KZ3HDX

[DavidM]

Also realize that the PWM HQST controller will produce 10-15% less power than a MPPT controller. But the Victron 15/50 MPPT controller which would work for two 100W panels is three times more expensive than the HQST but is not waterproof.

So the HQST is probably a good choice.

David

[nhlakes]

Ordered the above controller with similar panel from HQST for $30 less.  Some say it is the same panel shipped from Renogy with slightly different specs.

https://www.amazon.com/gp/product/B07QV8CDGZ/

Regardless, good enough for my little project.  Thanks for the help.  Stuff will be here in a couple of days and should install this weekend - and post pics.

Totaled to $213 with cables.

[nhlakes]

Panel, controller, and cables arrived, but I'm returning the HQST panel.

The box was slightly damaged (some time ago) causing no damage to the panel, but did force the panel to be stored bent in the box.  The panel is no where as flexible as I'd imagined, and has semi-permanently taken on the mis-shape of the damaged box. Appears the Renogy panel is MUCH more flexible, so I have ordered that one instead.

Pic that compares flexibility

https://cdn11.bigcommerce.com/s-fhnch/images/stencil/2048x2048/products/1427/18876/_02__10751.1582449084.jpg?c=2

[Merlin]

The Renogy is pretty flexible. I store mine flat in the original foam packing (without the box). For me, the flexible panels are nice not just for the flex, but for the very light weight. I'm looking forward to your install reports!