Solar Panels??

For a nice explanation of solar, try this link: Golden rules of solar Ever so much better than Handy(rant).

Handy Bob is always worth a read for all things solar and 12v and battery.

http://handybobsolar.wordpress.com

You just have to remember that he is focussed on fifth wheel trailers rather than truck campers that move a lot - hence his preference for open cell over AGM batteries.

Shadow Catcher wrote:
...If you have the option high voltage panels in conjunction with a MPPT controller delivers more usable current...

Be careful to check the voltage the panels you are looking at against the voltage the regulator will handle - my MPPT regulator has strict warnings about not to exceed a certain voltage (which isn't very high in its case). My panels don't exceed that voltage, but they get close. So check the specifications before ordering.

Make sure you use good thick wire - thicker than you would expect to handle the current - this will reduce resistive losses in the cabling - you don't get that much power from solar, so you certainly don't want to be losing any.

In my case I found a good deal on a all-inclusive kit. It contained a cheapo Chinese-sourced PWM controller. I decided to go with this, then once I had run it for a couple of seasons and was happy with the solar I upgraded the controller.

Steve.

Desertboy wrote:
Thank you M Mike, That blog answered every question I ever had about solar, and made me think of some new questions/ and then answered them.

Thanks, Desertboy and Pianotuna.

He stated that he works for a company making thin film panels so that is taken care of.
If you have the option high voltage panels in conjunction with a MPPT controller delivers more usable current, basically from sun up to sun down and in shaded camp sites. We have a 185W 66 cell high voltage panel on the top of our teardrop mounted flat feeding a Morningstar SunSaver MPPT. We spent 8 days on the north Shore of Lake Superior last June in a shaded camp site. Loads include a 12 Waeco refrigerator freezer LED lights, TV/DVD, XM radio, water pump,6gal water heater. We lost a little ground each day but at the end of eight days were at 64% SOC. I also have a 145W thin film panel I can roll out in the sun but did not need it.
Morningstar has a paper on the advantage of high voltage panels
http://www.morningstarcorp.com/en/suppo ... rimer2.pdf

Hi Mello Mike,

Solar 101 is excellent!

Thank you M Mike, That blog answered every question I ever had about solar, and made me think of some new questions/ and then answered them.

What I've read so far on this site can be misleading. For example, if your controller has a method of measuring load current, then you better have a controller that can handle the loads you use off your batteries. For example, I use a Morningstar PWM controller rated for 30amp loads. My jacks pull at least 30amps lifting the camper. The nice thing about this controller is that I can switch my load off. Great when storing the camper, I push a button and the load is disconnected via a solid state relay built into the controller.

Also, there are various types of solar panels. The best for size and efficiency is the monocrystal. I use 2 of these;
http://www.amazon.com/Instapark%C2%AE-Black-Mono-crystalline-Solar-Panel/dp/B004OZJ4FY/ref=sr_1_sc_2?ie=UTF8&qid=1386552972&sr=8-2-spell&keywords=monocyrstal+solar+panel


They have a STRONG frame, high quality glass and good efficiency for the size. Also, the Instapark brand makes great connectors and mounts for your camper.
These are white, but they come in black as well. They glue down to your camper roof using either a rubber superglue or any of the sealants used on camper roofs. The white shows them better for photos and also great for white roofs;
http://www.amazon.com/Instapark%C2%AE-ZJ-34W-Universal-Drill-free-Rooftop/dp/B008LMVV1Q/ref=sr_1_8?ie=UTF8&qid=1386553098&sr=8-8&keywords=instapark+mounts



Instapark also makes every type of connector you could need in just about any length. You can make your own as well.



start with a single 100watt panel and if that's not enough, add to it with either a second 100watt or 50 watt panels.

Here's the charger I use. It's small and it can switch in and out either the solar panels, the load or both. It also does full function testing from the front screen as well;
http://www.amazon.com/MorningStar-ProStar-Battery-Controller-30/dp/B0070OS4JS/ref=sr_1_1?ie=UTF8&qid=1386553417&sr=8-1&keywords=morningstar+charge+controller+PS-30



And lastly, if you work for a solar panel manufacturer, why are you not asking the staff there these questions? My bet is you would get some pretty technical advice that won't include all the 'well-it-works-for-me replies you'll get from laymen like us who have, or maybe even have not installed our own idea of what a solar plant should be. Quiz some of your engineering staff. I would bet they would LOVE to bend your ear on what they know. All engineers do you know! Cheers!

You've gotten some great advice so far from some very knowledgeable folks. I wrote this Solar Power 101 article a couple years ago that addresses some of the basics. You may find it useful. Good luck and let us know if you have any more questions.

Solar Power 101

Hi,

Yes take measurements of the roof. If you find a great deal on a 230 watt model that is 48" wide and 75" long, it probably will not fit anyplace on your roof without going over a vent or something. I have a pair of 39" X 60" panels on my roof, they are only 120 watts, that is about the maximum size I would recommend. Lay them out in cardboard first, making sure they will not get shaded by the antenna or A/C or something.

It is best to have them mounted 1" above the roof, the air circulating under them will cool them, and they produce more power when cooler.

I used 2" angle aluminum from Home Depot, 6" long to make brackets for the 4 corners. Ran the power lines down the back of the refrigerator to the controller. Use UV rated grey romex, rated for direct burial works fine (Home Depot).

You want to look for 12 volt panels with nominal out out of around 19 - 21 volts "Open circuit".

Look for a PWM controller rated for 10 - 20 amps.

You can use multible controllers for one battery bank, they will all try to keep the battery full, and will all shut off once you reach 13.8 volts.

This place has a great price on solar panels. SunElec.com

You can look for the balance of the system there or from many other places. I bought my solar panels from this place back in 1999. SolarOnSale.com

I found out about solar systems from this magazine. HomePower.com

Fred.