Making portable solar panels less annoying, on the set up side...quick and easy Options

[theresa p]

Thanks Gina

Looks good we tend to be going to Florida once a year now so we will keep that in mind.

Hi Bill

I did call that company they are about 1hr away was thinking of heading down next week. They are a bit more expensive though as I think he quoted me about 600 for a 100wat panel.

Need to gather all my needs first they see what he might suggest.

Thanks to All

Dennis

[Lisa H.]

I bought the panels from Sun Electric in Florida, but it appears as tho the 50 watt panels are no longer available.

They have 120 watt version for 309! THATS CHEAP!

I'm really interested in these Sun 120 watt panels but am not familiar with this type of panel. The website states that these are: "Made with high efficiency back-contact solar cells." The panel looks like it is polycrystalline. What am I missing? Since I'm not the engineering type, can anyone interpret the data/graph and tell me if these panels appear more efficient than say, amorphous or monocrystalline panels? The price sure is attractive.

Also, how large of a controller would one need to purchase if I got this 120 watt panel? Do I need anything else? I'm trying to get the full picture of the costs involved in adding this to my trailer and cost is a real concern. I already have a battery (probably need two with a panel this powerful!)

Lisa

This post has been edited by Lisa H.: May 30 2009, 01:24 PM

[Gina D.]

that panel is spec'd at 6.34 Amps so you could get by with a 7 or 8 amp controller..but I wouldn't do the bare minimum.

personally, the cost to go up is minimal and I would go with a 10 or 12 amp one. I have this one asc 12/12 just in case I add more panels later

It is my understanding that "Multi" crystalline and "Poly" crystalline of the same thing. Kinda makes sense in English.

[Lisa H.]

Gina, you must have responded while I was making a simular post elsewhere on the site. I get that etymoligically speaking, "poly" and "multi" have the same root meanings but the problem is that the description of the panels does not say either. In fact, unless I've just overlooked it, the description states that these panels are "made with high efficient back-contact solar cells." What are "back-contact" solar cells?

I will definitely get the controller that handles a larger load. Better safe than sorry. Thanks for the tip.

[Bill F.]

I'm really interested in these Sun 120 watt panels but am not familiar with this type of panel. The website states that these are: "Made with high efficiency back-contact solar cells." The panel looks like it is polycrystalline. What am I missing? Since I'm not the engineering type, can anyone interpret the data/graph and tell me if these panels appear more efficient than say, amorphous or monocrystalline panels? The price sure is attractive.

Also, how large of a controller would one need to purchase if I got this 120 watt panel? Do I need anything else? I'm trying to get the full picture of the costs involved in adding this to my trailer and cost is a real concern. I already have a battery (probably need two with a panel this powerful!)

Lisa

Hi Lisa,
It's a good idea to understand some of this stuff before you start spending money. For example have you done an Amp/hour calculation based on the intended consumption in your trailer? Maybe you don't need a 120 Watt panel. Have you converted to LED lights yet(1/9 consumption compared to incandescent bulbs)? . LED lights are expensive but cheaper than solar panels! If you need the 120 watt panel the next decision is what type of charge controller makes sense. The ASC12/8 [at] $42 is the inexpensive way to go but consider a PWM or MPPT type controller because they have 3 or 4 level charging which most deep cycle batteries prefer, and the MPPT allows using 24 or 36 volt panels which require much lighter(less expensive) wire between the panel and the controller, and the MPPT can harvest 10%-30% more power from a panel than the cheaper controllers will. The MPPT controllers are roughly $250 but if you can use a smaller panel and treat your batteries better(batteries are expensive as well) then it may make sense. Then you may want to have a battery monitor to know how many amp/hours are in your battery at any given time(eg can I run the furnace thru the night?), about $150. You didn't mention what you have for a battery. When you finish your Amp/hour calculation (without this you really can't make intelligent decisions about any of this equipment) you should have a battery that will store at least twice that many Amp/Hours because you shouldn't run a battery below 50% of full charge.

With LED lights(www.superbrightleds.com), a 115Watt monocrystalline panel, a 105A/H group 27 deep cycle battery, a Blue Sky Solar Boost 2512ix charge controller(see the controller and monitor at www.renewcanada.com), a TriMetric 2020 battery monitor, and some wire etc I will have spent nearly $1,300. The ability to stop and camp almost anywhere, priceless.
Bill

[Gina D.]

Lisa, when I spoke with sun on the phone, they said these were multi crystalline.. I googled multi and poly then and came up with the answer they are the same.

[Lisa H.]

Thank you, Gina, for clarifying what kind of panels they are. They looked like multicrystalline to me but the website did not make that apparent.

Bill,

In answer to your questions, I've been accumulating lots of LED fixtures from superbright.com and other retailers. When finished, my trailer will be a virtual beacon. I even have outdoor LEDs to go around the dog enclosures. I do not have a furnace but will eventually add this. I'd like to go electric with the heater if the solar panel will support one. In the mean time, I'm going to use use my Coleman Fat Cat propane heater. My other electrical draw will be my computer, which I use extensively for work and entertainment purposes. I want to use the laptop as a TV monitor as well. I'd also like to run some computer speakers and an IPOD docking station. My battery is a Marine Deep Cycle group 27 battery.

My brother has an 80 watt panel that I tapped into one week when I was camping and working on report cards out in the desert. I worked on the laptop for 6 hour stretches at a time and kept needing to recharge it. After using the solar panel to recharge the laptop, my brother was only left with 1.5 hours of energy to light his trailer and watch TV. While I'm aware that 120 watts may be overkill, I don't want to feel like my normal activities and work habits will be restricted while boondocking, but I also don't want to spend $1300 for a solar system and all the accoutrements. With the generous help from people like you and others on this website, I hope to learn what I should purchase that will meet my needs in a cost effective manner.

This post has been edited by Lisa H.: May 30 2009, 09:55 PM

[Gina D.]

you also might want to consider jumping up (?) :-P to the wally world group 29 at 125aH.. it's only 90 bones.

I got one the other day, it does just barely squeeze into a group 27 box as advertised and it is heavy, but not so heavy that I can't lift it.

[Bill F.]

Thank you, Gina, for clarifying what kind of panels they are. They looked like multicrystalline to me but the website did not make that apparent.

Bill,

In answer to your questions, I've been accumulating lots of LED fixtures from superbright.com and other retailers. When finished, my trailer will be a virtual beacon. I even have outdoor LEDs to go around the dog enclosures. I do not have a furnace but will eventually add this. I'd like to go electric with the heater if the solar panel will support one. In the mean time, I'm going to use use my Coleman Fat Cat propane heater. My other electrical draw will be my computer, which I use extensively for work and entertainment purposes. I want to use the laptop as a TV monitor as well. I'd also like to run some computer speakers and an IPOD docking station. My battery is a Marine Deep Cycle group 27 battery.

Hi Lisa,
The incandescant light bulbs you are in the process of eliminating draw somewhere around 7 Watts each, but a small electric heater typically draws at least 1500 watts so you may not have room on the roof of your trailer for enough panels to run that one and your axle probably wouldn't support the weight of all the batteries you would need. Stick with propane for heating and cooking. The computer and TV are OK. I went with 115 Watt hoping that it will do the job even on overcast days with it mounted flat on the roof(inefficient position). BTW I think solar and cost efficient may not be compatible.
Bill

[Gina D.]

its actually Dennis asking.. posting on Lisa's account.

Dennis, the absolute best way to use your computer in power critical situations (As in.. you may run out!) is to charge the battery with the computer off, and run the comp off the internal battery only. Thats what your comp battery was designed to do, and charging it while there is no other draw on it is relatively benign to your trailer battery. You are trickle charging that way, not powering it.

As a matter of fact, I don't even USE my trailer to charge mine. I actually have a 100w inverter that I use in my car, not my trailer. I run the battery down to nothing in the comp, and plug it into the car (Off.. car and comp, of course) give it an hour or so and I am back up and running again. I also don't have the slightest concern about my car battery that way. Every time I start my car, whatever minute amount used is recharge in short order.. with the trailer, I can only charge during the daylight.

For travel, I use an Acer netbook that can run for 8+ hours on a charge, but I use a full sized laptop the same way.

I use the car because its neater than having the power supply and inverter lying around in a small space.

Solar can be VERY cost effective once you get past the initial investment. And it need not be expensive (Relatively) to make that investment. The price keeps coming down as the technology and manufacturing methods improve. My 115 watts + all the stuff that goes with it to run it properly was under 500 US. If I had gone with mono crystalline panels, it would have been much higher.. but consider that application... we are not trying to feed back power to the grid, we are powering travel trailers. The 120 watt panel you are looking at cost even less than my 2 50 watt ones, and they are the same type of panels.

With solar, in the long term, once you are done.. you are done. No gas, no maintenance, no repairs. Thus, no additional costs.

[Lisa H.]

With solar, in the long term, once you are done.. you are done. No gas, no maintenance, no repairs. Thus, no additional costs.

I've been waiting for the prices of solar panels to go down and the efficiency to go up. It appears the time has arrived. Solar energy is a beautiful thing! It's so cool that once you have your system set up, you'll never have to go to the gas station to refill a tank or pay an energy bill again. I love the notion of being completely self sufficient.

Also, I wanted to say that I really appreciate all the support and patience that you folks provide neophytes like me.

Thank you,
Lisa

PS-
Who's Dennis?

[Gina D.]

Dennis is theresa ps.... er, hubby?

Sorry!... I am easily confused!!!!