Hi guys, a few of us were free camping at the weekend when I noticed the solar panels on the other vans were raised about 1/2" off van roof, my panel is mounted hard on the van roof. one of the guys said that I would be losing efficiency another said not, its an easy job to raise it but do I need to ?. on another point when connected to the car does the solar panel still juice up the battery or does the car over ride it ? I have a portable 120w panel ( same as van ) and were going to plug it in to the Anderson plug on the van, or is that to simple. Cheers
My research (driving everyone potty with questions, and surfing the net), showed me that the rated watts of a solar panel, are calculated using a formula when the back of the panel, is at 25 C. Also the back of the panel actually heats up, when it is working. Also the hotter the back of the panel, the less efficient it is. I interpreted this to mean that the panel should not be mounted flat on the roof, as it would not allow a breeze to cool it down
Simple alloy angle L plate pop riveted to panel with stainless screws through roof . About 20mm is enough . With sikoflex on both joins .. Check out the solar sub section .. For pics
Hi guys, a few of us were free camping at the weekend when I noticed the solar panels on the other vans were raised about 1/2" off van roof, my panel is mounted hard on the van roof. one of the guys said that I would be losing efficiency another said not, its an easy job to raise it but do I need to ?. on another point when connected to the car does the solar panel still juice up the battery or does the car over ride it ? I have a portable 120w panel ( same as van ) and were going to plug it in to the Anderson plug on the van, or is that to simple. Cheers
Hi Bass,
I think the answer about raising the panel has been answered. Yes it is considered better because it allows the temperature to stay cooler and that is good for efficiency. The standard distance quoted is 50mm clear.
To the second question. If the car is plugged in to the van it will only charge from the car when the motor is running and the voltage rises up to charging voltage. So if I read you correctly, if you are just parked then plug in your other panel. This assumes that it feed into your solar regulator with the other panel. If not then wire in another plug so it does. Without more information that is all I can say.
On the subject of panels keeping cool. If you have them free to the air at the back and propped up at an angle the panels stay a lot cooler that lying flat, be that on the roof or on the ground. My observations show this may increase the current by 20 to 30 % on a hot day. It also helps that it faces them to the sun better of course.
Jaahn
-- Edited by Jaahn on Wednesday 20th of April 2016 09:23:06 AM
Yea not realy when everything is hot .. But hopefully you'll have enough sun anyway .. A few holes carefully drilled on side supports maybe? But possibly easier to add another panel with gap ? Hmm ?? After initial cost ., It's like having another 50 more HP from your toe engine .,
The standard distance quoted is 50mm clear.
It also helps that it faces them to the sun better of course.
