Off grid camping tips

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Actually solar module designs haven't changed much in decades. It's a pretty mature technology, they are just much much cheaper now than they used to be. 
The bottom line is that solar cells are made from crystalline silicon. Like all crystalline materials, they are brittle. They will flex because they are thin but they will quickly develop small fractures and ultimately break. If you get a standard glass module then the nice thick glass superstrate will keep everything rigid as well as protect the cells from impacts like hailstones. The "flexible" modules have
a thin polymer superstrate that will not protect the cells from impacts or keep them rigid. Just check the warrantiy difference, glass modules come with 25-30 year warranties, "flexible" ones with 1 to 5 years tops. Generally the glass modules are cheaper too. 

The other issue lostagain raises is attaching to the roof. Solar modules are dark in color to absorb light. If you directly attach a "flexible" module to the roof it will make  both the roof and the module hot, which is bad for both. Glass modules can be stood off the roof a little so they and the roof stay cooler. 
There is also something solar modules can develop called hot spots. This occurs if a solar cell is damaged or broken. All the cells in your module are in series to build up the voltage (individual cells are only good for about 0.5V each) so the current is the same running through of them. If one cell begins to fail it will still be forced to carry the current of all the others so it will get hot. It can get very hot to the point where it burns or discolors the encapsulating materials and, if directly attached, the surface its attached to as well.

There is plenty of flat space on an rPod roof to mount a glass module, or you can leave it unattached and locate it where you want at the campsite. 

There is one type of flexible peel and stick solar module that you can mount to a curved roof surface, if you can find one. These were made by a company called Uni-Solar and are truly flexible, because they are based on a thin film deposition of amorphous (not crystalline) silicon on a stainless steel substrate. Because the thin film silicon is not crystalline, it can't develop fractures. You can even roll them up. The drawback with these modules is they are terribly inefficient, about 1/3 the efficiency of standard crystalline modules. That's why Uni-solar went out of business some years ago, but you can still sometimes find them on ebay etc. If the low efficiency doesn't bother you because you have enough room to mount what you need then you can try one of these, but they're big. They do still heat up the roof becasue of their dark color but they don't generally develop hot spots. 

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offgrid Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 23 Jul 2018 Online Status: Offline Posts: 5290	Topic: Off grid camping tips Posted: 23 Feb 2020 at 7:27am
	Actually solar module designs haven't changed much in decades. It's a pretty mature technology, they are just much much cheaper now than they used to be. The bottom line is that solar cells are made from crystalline silicon. Like all crystalline materials, they are brittle. They will flex because they are thin but they will quickly develop small fractures and ultimately break. If you get a standard glass module then the nice thick glass superstrate will keep everything rigid as well as protect the cells from impacts like hailstones. The "flexible" modules have a thin polymer superstrate that will not protect the cells from impacts or keep them rigid. Just check the warrantiy difference, glass modules come with 25-30 year warranties, "flexible" ones with 1 to 5 years tops. Generally the glass modules are cheaper too. The other issue lostagain raises is attaching to the roof. Solar modules are dark in color to absorb light. If you directly attach a "flexible" module to the roof it will make both the roof and the module hot, which is bad for both. Glass modules can be stood off the roof a little so they and the roof stay cooler. There is also something solar modules can develop called hot spots. This occurs if a solar cell is damaged or broken. All the cells in your module are in series to build up the voltage (individual cells are only good for about 0.5V each) so the current is the same running through of them. If one cell begins to fail it will still be forced to carry the current of all the others so it will get hot. It can get very hot to the point where it burns or discolors the encapsulating materials and, if directly attached, the surface its attached to as well. There is plenty of flat space on an rPod roof to mount a glass module, or you can leave it unattached and locate it where you want at the campsite. There is one type of flexible peel and stick solar module that you can mount to a curved roof surface, if you can find one. These were made by a company called Uni-Solar and are truly flexible, because they are based on a thin film deposition of amorphous (not crystalline) silicon on a stainless steel substrate. Because the thin film silicon is not crystalline, it can't develop fractures. You can even roll them up. The drawback with these modules is they are terribly inefficient, about 1/3 the efficiency of standard crystalline modules. That's why Uni-solar went out of business some years ago, but you can still sometimes find them on ebay etc. If the low efficiency doesn't bother you because you have enough room to mount what you need then you can try one of these, but they're big. They do still heat up the roof becasue of their dark color but they don't generally develop hot spots.
	1994 Chinook Concourse 1995 RV6A Experimental Aircraft 2015 Rpod 179 - sold

Pod People Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Senior Member Joined: 22 Sep 2011 Location: Chapel Hill,NC Online Status: Offline Posts: 1065	Posted: 23 Feb 2020 at 7:58am
	I would agree with GlueGuy that a suitcase system works great with the R Pod. We have used the Renogy 100 watt suitcase system for about 3 years and love it. We have a 25' cord and it allows us to move the panel around for maximum sun while still parked in the shade most of the time. the 100 watt system and 2 six volt golf cart batteries takes care of our power needs for almost any length of trip Vann
	Vann & Laura 2015 RPod 179