Solar panel expertise Please

[ice_maiden]

ok so I have a bit of extra money that I can put towards stuff I want for my mobile lifestyle. <br><br>I tend to be like Johnny Cash's Cadillac... one piece at a time. So I am starting to collect the parts for my solar array<br><br>So I found this solar panel for 189.00<br><a target="_blank" href="http://www.altersystems.com/catalog/unisolar-128-watt-pv-laminate-module-p-373.html"><br>http://www.altersystems.com/catalog/unisolar-128-watt-pv-laminate-module-p-373.html</a><br><br>I already have 2 trojan 8d batteries and the charge controller will be next.&nbsp; I have read and read and read on solar.... unfortunately I learn by doing. So any expertise will be greatly appreciated.<br>This panel claims 24 volts do I need 12 or can this be split to 12<br><br><br>

 

[ice_maiden]

Thanks Sparky1 ... I will look for a 12v panel then.. I take it you can't split the volts&nbsp; ... yes the 8d's total about 250 lbs BUT... they were free.. when they die I will go with something smaller I think<br>

 

[ped]

You can use 24v&nbsp;but you need an MPPT charge controller. The higher the volts the less amps you will get from it. A 128W panel at 33V like this will only give you about 35-40 amps per day in the summer with an MPPT to take advantge of the higher voltage. That is about equal to a 18V 80W panel with a PWM controller. <BR><BR>And that is a laminate so you have to solder your own junction boxes and diodes. That is why it's cheap.<BR><BR>Here's what I have. It will give you the same amp hours as&nbsp;that 128w and do it&nbsp;with a cheaper charge&nbsp;controller.<BR><BR><A href="http://www.ebay.com/itm/SOLAR-PANEL...&amp;hash=item4843562243&amp;autorefresh=true" target=_blank target=_blank>http://www.ebay.com/itm/SOLAR-PANEL...&amp;hash=item4843562243&amp;autorefresh=true</A><BR><BR><BR>

 

[akrvbob]

Did you notice that panel is 18 feet long?!! Where are you going to mount it? Last year at the RTR we installed two different Unisolar 64 watt systems, but they are only&nbsp; 9 feet long. Both people were going to roll them up and carry them under their bed and then lay them out on the ground every day. We put in a quick disconnect to make life easier. If you are in the Southwest, come by my winter camp and I will help you put your in.<br><br>Those are incredibly tough panels and that is an incredible price for one, just be sure you can make it work for you. The voltage won't be a problem, just buy an MPPT controller. The Morningstar Blue Sky is very highly respected and a decent price. Bob<br><br>

 

[akrvbob]

Sorry, I just read the rest of the posts and I need to make some corrections. First, the Uniroyal panels come complete with its own pre-wired junction boxes, no soldering required. Second, the job of an MPPT controller is to regain all the lost voltage above a nominal 12. Virtually all solar panels are 17 volt and above (I've never seen one that was less than 16 volt) so they all have some power loss--unless you use a MPPT controller that regains all the lost voltage. An MPPT controller will get you at least 25-35% more amps into the battery than a noraml controller, for any panel that is more than a nominal 12 volt, which is nearly all panels. Bob<br>

 

[ped]

<P>Keep in mind though, MPPT's Boost only happens like a 3-stage charger in the bulk stage. They're only in that mode when the batteries are down below ~80% capacity. From 80-100% they act like any other PWM charge controller. So depending on a few factors like the bank size you may not be getting down low enough on a daily basis to really take advantage of their boost mechanism. </P>

 

[ice_maiden]

ok maybe I will skip the panel for now and read some more...&nbsp; or check for a smaller panel ... no I did not notice that that panel was 18 feet long... my van now is only 17 feet (minivan) the next one should be big enough but I don't think I will take that chance... I've kinda got my mind set on the flexible panels... and if I was doing it for my current van it would have to be flexible because it has a raised roof conversion top on it..... all sloping and contoured...&nbsp; <br><br>I have been pricing solar panels for a while so yea I thought that was a really good price for that panel..... If anyone is interested I originally found them on Amazon @ 259. but it seems the same guy is selling them on ebay at 189. You can tell by their user ID<br><br><a target="_blank" href="http://www.ebay.com/itm/128-watt-Fl...of-Panel-Unisolar-Made-USA-/280784910929#shId">http://www.ebay.com/itm/128-watt-Fl...of-Panel-Unisolar-Made-USA-/280784910929#shId</a><br><br>Thanks for the replies everyone<br><br>

 

[akrvbob]

I hate to see you give up on the idea because it really is a great deal. Are you stealth parking in cities? If so then they have to go on the roof, but if you are boondocking in the country you could just set them out to charge during the day and then roll them up and store them inside to drive. Later when you get a fullsized van you could mount them on the roof. Or if you could find a deal on the 64 watt panels they would fit on the roof. Just a thought. Bob<br>

 

[ice_maiden]

oh no, Bob, I am not giving up the idea of solar.&nbsp; Just postponing it for a time I can be more sure I am investing in the right products for what I need... I can handle about any of this... but my solar knowledge is still just a bit lacking.<br><br>Every ideal has it's time ... I just jumped the gun on this one LOL<br><br>