Thoughts on using 24v panels??
- Thread starter 1leglance
- Start date
4x4junkie
Explorer
So many choices...no wonder people get in a quandary with solar
I like the idea of 1 24v panel for ease of install but I understand the concern over something happening to my 1 panel vs 2 smaller....off road I think that is a very valid concern. I can't seem to find smaller 24v panels, the only size so far is 29x65.
Anyone have any sources?
I hope this thread is of value to others. I have read many of the other threads here....and am still not sure what I want to do
If you're wanting a 24V input to your controller, another option might be to get four 12V panels in whatever size you need, and wire them up as two strings of two panels each (two panels in series making 24V together with another two in series making 24V). You could even go 6 panels for 3 strings of two panels in series each. This might allow you to fill up your rack space with panels more efficiently.
Note that one broken (or shaded) panel in a string would kill that entire string though (so in a 6-panel system as described you'd lose 33.3% of it's capacity to a single panel having an issue, not 16.6%).
Not speaking to electrical but physical characteristics now, I recently had it pointed out to me that, universally, large flatscreen TVs are palletized, shipped and stored standing vertically because when they are transported horizontally they experience increased incidences of cracking due to the way the force is distributed and applied to the large screens. Something to do with the span, weight and g-forces from vehicle movement and such. I believe that glass vendors ship glass the same way for the same reason.
With hard mounted vehicle mounted solar panels I would think that multiple panels would be of a benefit in that the spans of the glass are of a smaller area, and the weight support per panel would be less. Imagine a 2 foot by 2 foot piece of glass suspended around its' perimeter. The amount of g-force applied required to crack it would be much less than 4 1X1 panels as it would be less weight supported over a shorter span.
I haven't experienced this myself as my panels are about 40" by 15" but mine are inside the camper sandwiched between the mattresses and a piece of foam underneath supporting the glass. Someone else who has experience with hard mounted vehicle solar panels while driving off road may be able to address this.
With hard mounted vehicle mounted solar panels I would think that multiple panels would be of a benefit in that the spans of the glass are of a smaller area, and the weight support per panel would be less. Imagine a 2 foot by 2 foot piece of glass suspended around its' perimeter. The amount of g-force applied required to crack it would be much less than 4 1X1 panels as it would be less weight supported over a shorter span.
I haven't experienced this myself as my panels are about 40" by 15" but mine are inside the camper sandwiched between the mattresses and a piece of foam underneath supporting the glass. Someone else who has experience with hard mounted vehicle solar panels while driving off road may be able to address this.
Lance;
You might want to check out this site;
http://solarseller.com/
Info there seems to confirm your report that 24v panels can be used to handle the voltage drop before converting to 12v. However, this seems to apply to long distance runs from panel to POU, which wouldnt be the case on your truck.
Note also the MPPT controllers he is selling, much less than others on the market, and in stock.
You might want to check out this site;
http://solarseller.com/
Info there seems to confirm your report that 24v panels can be used to handle the voltage drop before converting to 12v. However, this seems to apply to long distance runs from panel to POU, which wouldnt be the case on your truck.
Note also the MPPT controllers he is selling, much less than others on the market, and in stock.
rayra
Expedition Leader
If you want to also run a 24v inverter directly off your panels, I've just listed some ProWatt 800s for sale here http://www.expeditionportal.com/forum/threads/135456-ProWatt-800-24V-power-inverters