Help me buy a solar panel

[Dirtpig]

I need advice on what solar panel to purchase. I have 2 group 31 batteries holding i think 220AH. All we do is dry-camp, only plugged into electricity a couple times. Electrical needs are very minimal, we do not run any electronic gadgets other then the radio/cdplayer. Even lights are not used all that much as we spend 90% of our time outside. In the winter this changes to more lights and more electicity used because of the furnace but i figure solar is going to do very little for me in the winter time if anything. Right now (in summer) we are able to camp for about 5-6 days with the batteries going down to about 12.1-12.2V and then i will run the generator. I am hoping to get away from this generator use all together.

We live/camp in mountainous terrain so i would say 6hrs of good sunlight at best, probably fair amount of shadows during the day cast onto the panels from trees as well.

I already have a solar panel controller (Specialty Concepts Mark15, 15amp) I was thinking a 100watt solar panel would maybe be OK, should I go bigger? Should I add more then just 1 panel? Tons of room on the overhead cab part of the camper but its slightly angled downward.

What do you think?

Good brandname? specs to look out for?

Probably purchasing in quartzsite AZ unless you know of a good place to buy.

[Reddog1]

It has been years since I bought my panels. I bought from Northern Arizona Wind & Sun. They were easy to talk to, about as helpful as anyone could be. I called them several times while deciding what I wanted. They had several employees, and at the time a couple were relatively new to solar. They did not hesitate to say they did not have an answer to a given question, and always ask someone else at the store, or found the answer and called me back.

I felt very strongly about tilt panel mounts. The owner said he would sell them to me, but advised against it. I ask why and he responded it is too easy for people to forget and leave them up, resulting an damaged panels and/or roof. He also said before long, I would find that even though it was a gain, most tire of the raising the panels. As it turns out, I made my own mounts, and he was right it did not take long to tire of the process. Maybe in some parts of the country it is worth while, but not for me.

Northern Arizona Wind & Sun is pretty diverse, not specializing in RVs only. They have many solar related products for many applications. There are a lot of self proclaimed experts that read a little, and pass on information that may not be entirely true. What I really liked about Northern Arizona Wind & Sun is their product line is so huge they do not have to sell products using untruths. You want it, they have it and will sell it to you even while advising you against the purchase and explaining why.

Northern Arizona Wind & Sun also has a Forum, Solar Electric Power Discussion Forum by Northern Arizona Wind & Sun, with pretty good info from the Forum members.

As I said, it has been years since I have purchased from these guys, but I doubt they have changed much, other than for the better,

Wayne

[pianotuna]

Hi covered,

Shade tolerant panels have diodes between each and every cell. Amorphous panels are better in low light conditions--but take up much more space per watt. But shade is to be avoided if possible.

[covered_wagon]

Thank you Kerry and Pianotuna. I've heard some panels cannot do well even if only one corner of the panel is shaded. I think it depends on whether each cell is wired together in series or a single circuit. Something along those lines anyway.

Do all you guys have the multi crystal type (they look like a crystal surface) or the other type more like a single consistent facing?

[CA_Traveler]

2oldman wrote:

kerry4951 wrote:
I never saw a need to make my panels "tilting".. The solar dealer in Quartzsite actually recommmended against it.

You might if you are camping in winter.

I'd like to know the reason behind the recommendation against it. It's likely the dealer is 'reading' you and agreeing with you to enable him to more easily sell you another panel.

The two major Q dealers are in the business of selling and installing. Flat mounted means more sales and neither dealer is above that. I've talked to both of these dealers and would not consider using either one for advice or installation.

But a good reason not to tilt besides roof climbing is wind. With a strong wind gust you might be up on the roof making repairs.

[pianotuna]

Hi covered wagon,

In leafy shade, at solar noon, I get 80 to 100 watts from 256 watts of panels. That works out to about 35 amp-hours per day returned to the battery bank.

I do have Uni-Solar panels which tend to be more effective in low light situations than most other designs.

[kerry4951]

covered wagon wrote:
Are solar panels a viable solution even for a camper that only camps in the shade?

You should still get some action from the solar. I park under an enclosed carport with only the front end open. The panels never get direct sun, but they still produce enough to keep the batteries up to par while the TC is stored.

[covered_wagon]

Are solar panels a viable solution even for a camper that only camps in the shade?

I've been using my Honda to charge.

[pianotuna]

Hi Tom,

You may find the handybob site wordy and it has some information that is dated at best.

Try these sites instead:


http://rvroadtrip.us/library/12v_system.php

http://rvroadtrip.us/library/solar_install.php

[Tom_M1]

Wayne, you summed things up nicely.
Here's some web sites that I found helpful:
jackdanmayer.com
rvroadtrip.com
handybobsolar

[Reddog1]

My suggestion is to look closely at your where you can mount your panel/s. Mount the minimum solar panels you think you may need, but make sure your wiring and control panel will allow for adding panels if you decide to add later.

Do not waste money on tilt mounting. It will be great the first few times out. You climb out on the roof, drawing a crowd to impress them with your solar. The will not be impressed, when it is raining while you are outside lowering them. They will have a good laugh when you drive off having forgot to lower the panels. If your mounts are really strong, you may not only destroy your panel/s, but rip your roof apart also. Mine tilt, but only when I am experimenting with them. Technically, tilting adds more watts, but realistically, in the long term a waste of time in my opinion.

I installed two 65 watt panels, one on each side of my escape hatch. I can stand on my bed, reach through the hatch and clean the panels. Why two 65 watt and not one 130-watt? I can loose (shade or physical damage) one panel, and still have 60-watts. I did pay $40 more for two panels. Neither panel is perfectly horizontal, and with experimenting with leveling the panels, I can see no noticeable difference. In theory horizontal would be best.

I have one 100 AH AGM battery. I have no parasitic loads. I lived in my TC for four nights per week, for five years with no hookups. I started my generator about four or five times per year to charge the battery. That was with several days without sun. I ran my lights, TV and laptop, for about 4 to 6 hours per day.

I have a Wave3 and all LED lighting. I use my furnace only for backup or quick heat. I have had my system for about seven or eight years, and I have no need for a second battery or additional solar. I have space on my TC for at least an additional 260-watts. I have space for an additional 100 AH battery. I do live in California, lots of sun.

I think Quartzsite AZ or a RV specialized solar distributor would be my last choice to buy solar for my TC. It is kind of like buying a T-shirt at a tourist shop. If you have no mechanical skills, no time, no interest, lots of money, then Quartzsite AZ or a RV specialized solar distributor is a good choice.


Wayne

[trail-explorer]

http://www.amsolar.com/ is another place to look in to. They have a variety of panels and controllers.

Also consider upgrading to LEDs for you lighting too. Here's some plug and play LED replacements that a number of TC owners are using.

[pondlady]

If it were me, I'd just buy one panel, get the tilt brackets and try to not park under trees. If you're parked in the summer for 5 days it is probably feasible and cost effective to get on the roof and tilt the panel. If you park under trees the panel(s) won't get enough sun to work properly, be it one or two....IMHO.

[AnEv942]

agree & 14% isnt that bad at least compared to some-
http://sroeco.com/solar/ is a good source of info-one of many. Enough to confuse even more.
I personally went with a 'name' in case of warranty issue. Course I cut the silly MC connectors (and warranty) off so I could hardwire.

[KD4UPL]

Don't be too concerned about solar panel efficiency. That is basically just an expression of physical size versus output. Efficiency is very important when you are paying for the "fuel", with solar the "fuel" is free. A 100 watt panel that is 17% efficient will be slightly smaller than a 100 watt panel that is 14% efficient. That's about it.

[2oldman]

kerry4951 wrote:
Just read the previous post by AnEv942 and that describes to a "t" what the dealer told me and why.

IF those reasons are good enough for you, so be it. Many I've talked to try to 'eliminate' tilting by buying more panels.