Solar Panels - On Roof or Portable- What’s Best

[Jane P.]

I did not want to hijack the rooftop solar panel thread, so I am starting a new one.

As a boon-docker, I’m always thinking about adding solar to my Bigfoot 19. And, as I have zip space in my TV, rooftop panels seemed to be the most practical course.

However, during a message exchange with another Bigfoot owner, he laid out a compelling argument for stand alone panel:
For one thing, if your campsite is in the shade, your rooftop panels won’t work.
Between trips, the rooftop panels need to be covered, which could be a real pain.
You will be using space that you may need for, say, a new vent ( my concern).

So what say you?

And ... for those of you with portable solar panels, where do you store them? Where do you put them when traveling? How do you protect them en route? How heavy are they? How hard is disconnect and stow them when breaking camp? If you leave your campsite during the day, how do you secure them?

[Jon Vermilye]

Originally Posted by Jane P.

I did not want to hijack the rooftop solar panel thread, so I am starting a new one.

As a boon-docker, I’m always thinking about adding solar to my Bigfoot 19. And, as I have zip space in my TV, rooftop panels seemed to be the most practical course.

However, during a message exchange with another Bigfoot owner, he laid out a compelling argument for stand alone panel:
For one thing, if your campsite is in the shade, your rooftop panels won’t work.
Between trips, the rooftop panels need to be covered, which could be a real pain.
You will be using space that you may need for, say, a new vent ( my concern).

So what say you?

And ... for those of you with portable solar panels, where do you store them? Where do you put them when traveling? How do you protect them en route? How heavy are they? How hard is disconnect and stow them when breaking camp? If you leave your campsite during the day, how do you secure them?

I prefer both. I have 2 160 watt panels on the roof, and carry another 160 watt panel in the truck for the times I'm in the shade or need more amp hours.

[Byron Kinnaman]

There are many things to consider when adding solar. Roof vx portable, less than 100 watt or more than 200 watts. What are your needs?
Do a quick survey and find out what your daily usage is. Will you be using more than 10 amp hours per day or maybe less than 1 amphour per day. Once you've determined usage then you figure out how solar you need. Then you can consider portable vs roof mounted.

As can see it not a simple matter of adding 300 to 500 watts of solar to be efficient. You can add that much and be putting a lot more $ into it than necessary.
For me I prefer portable and follow the sun. That way I can park the trailer in the shade. Also I don't have to worry about the panel(s) blowing off when traveling. Others like to camp in the sun. Your choice.



If you're going be mostly or only camping with electricity hookups solar is of no value to you. With a little conservation you don't need solar for up a week of camping. But if you desire is be like others have solar to brag about, go ahead and all the solar you afford.

[Air Doug]

This is our first long trip with the solar panel. I am very happy with the portable panel. I can park in the shade on hot days and put the panel in the sun. I can park in the sun and easily move the panel to follow the sun.

Set-up and tear-down are quick and easy. I use Anderson connectors on the trailer side because they are so small, well-designed, and easy to use.

RV is a Lil Snoozy so it is easy to store a panel (or two) in the basement under the bed. Panel weight varies but is advertised. Mine is easy to carry and load. I store it glass side up and don't put anything on top of it.

Doug

[Huck]

It's easy to have 1 roof mounted and 1 portable. You just connect the 2 panels using a y cable and you can plug/unplug the portable panel as needed.

[ZachO]

I would love to have both, but for now the portable panels I have are the most convenient, if I'm only going to have one kind. I set up camp in the shade if possible, and if I'm worried about theft, I just do this.



From this past weekend. I trailer camped a night up near a trailhead, then backpacked in to a lake for a night. Wasn't sure I wanted the panels out where they'd draw attention, but needed the batteries charged. I've done this in town before, too, at the office parking lot if I'm going on an overnight work trip. Not foolproof, but better than panels just sitting there on the ground.

When I head to work for the day, I just leave them set up. So far, they've always been there when I get back. This is a pretty safe area but I definitely worry a bit. People around here leave all sorts of stuff out around camp and leave for a few hours, though. I know theft is a very common problem in some areas but not so much here.

I've seen less bulky setups, but my panels are heavy. With the case, definitely up around 30lbs or so. Not totally sure. I keep them in the back of my truck in the case, against one side with a ratchet strap holding them in place. To get them out, set up, and put the case away back in my truck it takes probably 5 minutes. Mine is a real simple set up. I have attachments at the battery terminals that stay there, screwed down with the other battery cables. That wire has a disconnect, and my panels just plug right into that. So I just reach up under the battery/propane cover, grab the loose wire/connector, and plug my panels in.

[IMEd]

Some have said,

1) “Between trips, the rooftop panels need to be covered, which could be a real pain. “
Quite the opposite is true. You want the solar panels to keep your batteries charged when your rig is in storage. Don’t cover them.

2) .”..panels blowing off when traveling..”
Properly installed solar panels will not blow off while traveling. In fact, properly installed panels can be quite difficult to remove.

[Byron Kinnaman]

Originally Posted by Ed Colorado

Some have said,

1) “Between trips, the rooftop panels need to be covered, which could be a real pain. “
Quite the opposite is true. You want the solar panels to keep your batteries charged when your rig is in storage. Don’t cover them.

2) .”..panels blowing off when traveling..”
Properly installed solar panels will not blow off while traveling. In fact, properly installed panels can be quite difficult to remove.

Properly installed is the operating phrase.

[sharpstick]

Originally Posted by Jane P.

For one thing, if your campsite is in the shade, your rooftop panels won’t work.

I would just store them inside the RV. They aren't that heavy. I would make sure they are stored flat so they don't fall over. In addition to carrying them to a sunny spot, having them portable makes it easier to tilt them so they are perpendicular to the sun. This is more important than most people think if you want to maximize charging.

[stevebaz]

I use 2 small 30 watt panels connected together with a 2 foot or so wiring and about 20 foot lead. I drive to a spot and put these two panels along side the roof escape hatch. Being tied together straddling the roof hatch keeps them from blowing off the roof and from being easily walked away when not in camp. Some day I will no longer be able to climb up on the bed to put these up so then they will become ground mounted. If I can't climb up to put panels on the roof I sure can't clean panels permanently mounted up there. If I had a Scamp 19 then maybe I would rethink mounting panels on the roof. With the loft bed and much more real estate to work with I could see going roof mount. I would put an escape hatch there if there isn't one already. Out west we camp year round so pitching the panels from top of trailer to the side can be important in the winter time.

[WaltP]

I have a 160W roof mounted panel and a 100W portable with a long extension cord (10 gauge).
I find the combination very flexible for almost all situations. I also have a 1500W inverter that I use for a microwave and other AC appliances.
The portable is a Renogy suitcase and I just lay it flat on the floor while travelling.

Walt

[Tioga George]

Hi Everybody!

My rig consists of a Ford Transit tow vehicle and a 13-foot Scamp.

I've mounted a 250 watt solar panel on the Ford Transit's roof. The solar panel's output cable is routed thru the roof and connects to a Renogy battery charge controller located in the Ford's storage area.

The solar battery may be located inside of the Ford or inside the Scamp.

In order to cable the Scamp to the solar power, a solar cable goes thru the Ford's floor and runs next to the 7-pin connector. To provide for solar cable disconnect, a 20 amp connector and matching 20 amp plug are used.

George


.

[Gompka]

I have found that a renogy 100 watt panel will fit behind the upper bunk (back of the couch) in my scamp 13.

[Jon Vermilye]

One advantage of rooftop panels is they work while you are driving. Again, I prefer both.

[ehoepner]

I have one 80 watt solar panel mounted on the roof of my 17 ft Casita SD. That panel has been there for 7 years now. It is permanently mounted, it gets covered during the time I have the trailer covered. It has travelled thousands of miles with no special treatment. Oh, it needs to be washed every now and then to get the bugs off the front edge and clean the panel itself.


My purpose for this solar panel is to recharge the battery when we are dry camping. I have a group 29 battery installed. It takes about 4.5 hours under full sun to recharge the battery. If we are parked in the shade it takes all day. When we are dry camping we use the lights, the water pump, and the furnace. The frigirator and the water heater are on gas.


We do not have a TV, we are camping, away from home. During the day we hike and are generally outside all day. At night we play games, read, or play a movie.

The solar panel puts out enough power so that if we stop at a restaurant to eat I don't have to turn the frigirator off to keep from running the vehicle battery down.


The setup and operation is very simple and it does what I need it to do. I'm very happy with what we have.

[Jim Bennett]

I went with the idea of using both in my recent installation. I mounted 240W directly to the roof, and carry an 80W for times when the gain on the trailer is poor. In 1 1/2 years now I have yet to use the portable, as the rooftop ones have always fully charged the batteries by early afternoon or earlier.

[Jane P.]

Walt, thank you for your response. I would appreciate more details re your microwave. My energy requirements are fairly modest, but when preparing dinner, I need my generator to power my microwave. Usage can vary from several minutes defrosting and heating up frozen entrees to nuking vegetables and other side dishes.

So, with solar, your 1500W inverter will power your microwave? How much power does your microwave draw with the inverter at dinner time? Do you have to limit microwave usage? If so, what is the maximum amount of time you can use the microwave? After you finish using your microwave, can you continue to use other appliances before bedtime, or are your batteries depleted?

Thanks,

[Jon Vermilye]

Originally Posted by Jane P.

Walt, thank you for your response. I would appreciate more details re your microwave. My energy requirements are fairly modest, but when preparing dinner, I need my generator to power my microwave. Usage can vary from several minutes defrosting and heating up frozen entrees to nuking vegetables and other side dishes.

So, with solar, your 1500W inverter will power your microwave? How much power does your microwave draw with the inverter at dinner time? Do you have to limit microwave usage? If so, what is the maximum amount of time you can use the microwave? After you finish using your microwave, can you continue to use other appliances before bedtime, or are your batteries depleted?

Thanks,

There are two major things to consider on using a microwave - battery capacity & the ability to recharge the battery.

I can be specific with my system. 320 watts of solar on the roof & a 160 watt portable panel added when necessary. Batteries are a pair of 6V deep cycle with 220 amp hour capacity. When in a semi permanent location (more than a week) I tilt my rooftop solar panels to take advantage of a better angle to the sun than flat. It is rare that I need to add the portable panel even during the low angle winter sun & short days if I tilt the panels. When parked in the shade, I usually add the portable panel. During the high angle summer sun, I usually don't need to tilt the rooftop panels.

As to the microwave, I have an RCA 700 watt (900 watt input) microwave running on a 1500 watt GoPower sine wave inverter. It draws around 90 amps at 12V when running on full power. How long I can run it depends on what I expect to have in the way of sunlight to recharge the batteries. I prefer not to go below 80% on the batteries, although you won't do much damage going as low as 50%.

If the microwave was the only thing drawing from the batteries, I could expect to be able to run it for a little less than 1/2 an hour at full power before the batteries would get down to 80% (assuming they started at full). Unfortunately, I have many other loads since I'm just about full timing (3-4 months in the desert without hookups) so a half hour run would be impractical. I generally use it to reheat left overs, a frozen burrito or fast meal, frozen soup, etc. Typical runs are under 5 minutes. With those typical runs, I can still use the rest of the trailer appliances, although if there is going to be multiple days without sun in the future, I switch to the propane stove or oven or cook outside (I prefer to do that most of the time anyway).

This year I replaced the RCA 700 watt microwave with a Panosonic Inverter, a NN-SD372S. While it is a 950 watt vs the RCA at 700 watts, it doesn't draw much more because of the inverter technology. It draws less at lower powers & defrost which is easier on the batteries & food, since a standard microwave switched full power off & on to defrost or run at lower than full power. We will see if it is an improvement.

Hope this helps...

[WaltP]

Jane
My microwave is a 700W unit.
How much you can use it will depend a lot on your battery capability. I probably should have said that I have 2 6v golf cart batteries, which makes a big difference.
If those batteries are charged to the max I found I could
Run a Black & Decker 12 cup coffee maker, and following that
Run the microwave for 11 minutes.
The 12 cupper makes enough coffee to last me 2 or three days, storing the coffee in a stainless steel thermos.
So other mornings I'll use a regular 2 slice toaster and heat a couple of cups of coffee in the microwave.
During the day I'll typically run the microwave several times to reheat some coffee and the solar panels will recharge the batteries.
I generally don't need the inverter much in the evening, except maybe to reheat a precooked meal, 2 or 3 minutes. Using it much in the evening will mean no use the next day till mid day.
Of course cloudy days limit usage but having the two solar panels does help a lot.

I hope that helps.

Walt

[Jane P.]

Byron,
Thanks for your thoughtful response. Regarding you portable panels, where do you store them when underway? How heavy are they? How easy, and important is it to position and reposition the panel in relation to the sun?

FYI, I primarily dry camp for several weeks at a time, and have tricked out my trailer to minimize energy usage: I converted to (warm) LED lighting years ago, installed LED Captain reading lamp over my Gaucho couch & the dinette. I also strategically placed 12 volt “cigarette”/USB outlets in the cabin. I am very careful to turn off the water pump when not in use. I also exchanged my single battery with two marine batteries.

As an aside, my MO is to reduce cabin lights in use as the evening advances. The Captain lamps are great additions. They allow each of us to read and write without disturbing the other. If one of us need to take a dog out in the middle of the night, my husband uses the reading light to dress without disturbing me.

But, the pièce de résistance is battery powered “voltage” candles for the dinette area (dinners by candlelight and minimal illumination before bed) and the bathroom (as a night light). These candles mimic the real thing, add a sense of warmth to the cabin’s ambience, and allow me to forego bathroom ceiling light in the middle of the night. The ones I bought have in timers, so I don’t have to get out of bed. I bought one on Amazon several years ago, and a second candle at Home Depot earlier this year.

All these things have worked well. A generator sits on my trailer’s back porch, and I go several days between charges. The only additional thing I can do I is add solar.

I have no idea how many amps per hour I currently use or will need in the future. Your questions remind me to get a high quality voltage meter.

I need my generator for the microwave, and would love a solar system which let me bypass the generator and continue to satisfy my nightly energy usage. I do not watch television, but I do listen to a 12 volt auto stereo system whenever I am in the trailer.

The trailer came with an AC, but ... hey. On warm days, I’d like to maximize air flow through the trailer. To that end, I plan to add ceiling vent and Maxifan aft of the AC unit. I can envision using a 12 volt fan all afternoon & night, and have no idea how this would add to my load. So, I may require solar in the future.