74 replies to this topic

[DavidO]

I have to ask the question why a 160 watt solar panel. Is it because FWC does?

 

I have a 160 watt Grape solar panel and it work great so while it is a good choice it is not what I would chose today. The reason that I have a 160 watt panel is that was the highest watt rigid panel that was a 12 volt panel at the time. My panel and  mounting hardware comes in at 26 pounds and that replaced a 17 pound 95 watt factory panel. So only 9 pounds added. If you were to a 24 volt panel the weight goes way up fast to around 40 pounds.

 

Today there are several 12 volt panels that are 180 watts they weight the same as the 160 watt panel and are about the same dimensions. Though 20 watts is not much every little bit helps.

 

The question comes back to which 180 watt panel? I tried Amazon but $300 shipping was crazy. Looking farther you can get a 180 watt Grape Solar Panel at Home Depot for $258. I'm sure that there are better deals to be had with further research.

Edited by DavidO, 11 January 2018 - 04:58 PM.

[Wallowa]

Still planning my build.

 

The plan was to swap over my (2) 100 watt Renogy panels from my truck to my hawk.

 

However...  with the (2) roof vents, it appears they wont fit.  Someone on here provided me a dimension of 38" between the vents.

 

Between the vents is where I would like to mount my panels (or maybe just one big panel)

 

Behind the vents ill be mounting maxtrax'

 

Looking for options.  Anyone use the "NewPowa" brand?

 

Want to maximize wattage, but have the install look clean.

 

Thanks

 

SoCal,

 

Slightly off solar panel question, but you mentioned Maxtrax mounting behind roof vents...how do you plan to mount them?

 

Yes, I plan to spring for a set of Maxtrax and at 45" in length they may not fit in Access Cab area of our Tundra...they are light so a roof mount is my next choice..we have FWC installed 160w mounted on Yakima Trax.

 

Thanks...

 

Now back to solar!

 

Phil

[Vic Harder]

I have to ask the question why a 160 watt solar panel. Is it because FWC does?

 

I have a 160 watt Grape solar panel and it work great so while it is a good choice it is not what I would chose today. The reason that I have a 160 watt panel is that was the highest watt rigid panel that was a 12 volt panel at the time. My panel and  mounting hardware comes in at 26 pounds and that replaced a 17 pound 95 watt factory panel. So only 9 pounds added. If you were to a 24 volt panel the weight goes way up fast to around 40 pounds.

 

Today there are several 12 volt panels that are 180 watts they weight the same as the 160 watt panel and are about the same dimensions. Though 20 watts is not much every little bit helps.

 

The question comes back to which 180 watt panel? I tried Amazon but $300 shipping was crazy. Looking farther you can get a 180 watt Grape Solar Panel at Home Depot for $258. I'm sure that there are better deals to be had with further research.

David,

 

Keep in mind that:

 

1) Your solar controller may drastically limit how much of that power you get to use.  I looked up those panels on GrapeSolar.com  The 180W US made version puts out 19.67v at 9.15A to make 180W.  The typical (PWM) solar controller fitted to our campers from the factory will only make use of a nominal 13.8V (fully charged AGM battery) + 0.5V = 14.3V to push the charge into the almost full battery = 14.3*9.15 = 130W.

 

2) A MPPT controller will try and make the max power, and so get more of that 180W into your batteries.

 

3) The most you are likely to see is 80% of rated power getting to your batteries, given practical realities of dirt/shade/temperature/angles, etc

 

4) The reason for #1 above is because a PWM controller will literally "toss away" higher voltages, and this is why a "12V" panel typically has their cells arranged to limit voltage and maximize current.  Thus, a 12 V panel that makes 10A at 15v = 150W will push more power into your battery via a PWM controller than a 150W panel that makes 25V and only 6A.   

 

5) Given the 80% rule mentioned in #3 - and combining it with the max voltage you can make practical use of = 13.8+.5 = 14.3, can see that you will want a panel that makes the most power at 14.3/80% = 18v. That means a 180W panel that puts ouf 180/18 = 10A.  

 

The Grape Solar panel under discussion is pretty darn close, at 9.15A.  

 

I hope that helps you in your shopping for a panel!

[So Cal Adventurer]

Wallowa

 

I ordered my Hawk with the Yakima tracks.  Based on pics I've seen the tracks continue to almost the very rear edge of the camper.  I am thinking of making some sort of mounting system to mount them rearward of the rear vent in between the rear vent and the rear end of the roof.

[Wallowa]

Wallowa

 

I ordered my Hawk with the Yakima tracks.  Based on pics I've seen the tracks continue to almost the very rear edge of the camper.  I am thinking of making some sort of mounting system to mount them rearward of the rear vent in between the rear vent and the rear end of the roof.

 

 

Right, got that..guess my question was fuzzy...I also have the same tracks from FWC; what I am interested in how you intend to attach the MaxTrax to the Yakima tracks.  I did not see that you have not received your Hawk;  when you do let me know what you figure out for attaching the MaxTraxs. 

 

Thanks,

Phil

[So Cal Adventurer]

Ah, gotcha, correct, I have not got my Hawk yet, supposedly mid February.

 

I will most likely be making a aluminum mounting system from angle iron like they do with the solar panels.

[Wallowa]

Ah, gotcha, correct, I have not got my Hawk yet, supposedly mid February.

 

I will most likely be making a aluminum mounting system from angle iron like they do with the solar panels.

 

 

Just check...my  '05 Tundra Access Cab has 48" of usable width in area where I store most of my gear in stacked rubber maid boxes behind the front seats [I removed the back seats and hardware...now a storage area] and since the Maxtraxs are 45" long I will most probably stow them there rather on the roof....

[So Cal Adventurer]

Just check...my '05 Tundra Access Cab has 48" of usable width in area where I store most of my gear in stacked rubber maid boxes behind the front seats [I removed the back seats and hardware...now a storage area] and since the Maxtraxs are 45" long I will most probably stow them there rather on the roof....

Nice!

Check out my build link below. The rear area where my sears used to be is full now.

[ottorogers]

If anybody here to give me advice on which flexible solar panel to buy I would really appreciate it, I’ve read a few posts hear about which ones to avoid, much appreciated

[rando]

I have only had mine for less than a year so I can't comment on longevity, but the solar Cynergy 120W panels seem to perform to their specifications at least when new.  The problem is no one has had any of these panels for more than a few years, so knowing which ones will last is purely a guess.   

 

Also, with a compressor fridge in shoulder season you will likely need > 120W of panel.   I currently have 240W, which seems to be able to keep up year around, but previously my 160W panel was not quite enough when solar angles were low.