Flexible Solar Panel Installation

[Mountain_Biker]

Hi, just in case anyone is interested, I have just installed a Flexible type Solar Panel on my Rapido Motorhome. I went this route for weight considerations, more a precaution rather than needing to. The flexible solar panels are about a kilo, the rigid ones are ~8kg plus fittings. I wanted to keep the panel off the roof for two reasons, 1) be able to replace if needed, 2) some concerns from technical forums about the panel getting warm when working and affecting the output - so wanted some ventilation around it and under it.

 

Flexible is an odd name for my solar panel, if is effectively solar pads stuck to a strong aluminium sheet, so reasonably rigid, slightly flexible would be a better term. Mine is a Biard 100w

 

Out of plastic electrical trunking, I made some mounts - front, sides and middle. I reinforced these by pop riveting aluminium rectangular section inside the trunking. These were stuck on the roof with mastic and the solar panel then pop riveted to these (through the aluminium). I could have used self tapping screws but elected for pop rivets, easy enough to drill out. Works out cheaper than buying the mounts for the rigid panels also.

 

The end result has kept the panel off the roof. Other threads have indicated they have stuck the panels direct to the roof, but I wonder how you get them off?

 

Wiring on the Rapido is fairly easy since they pre wire for solar panels, there is a good French thread that gives excellent detail also. In addition to the standard wiring, I stuck a switch in the panel output, just allows me to "switch the panel off". Although the controller i selected has voltage cut off above 13.8v.

 

The regulator I selected has lots of pretty icons on a nice LCD screen, but interpreting the manual remains a challenge....fortunately the factory settings are good enough. But I can time it for dawn and dusk, how on earth it knows that since there is no clock in it, I have not figured out yet. It also has a second output which I could connect to the van battery, but I am not worried about this one.

 

Anyway, chuffed and the battery voltage is up.

 

Why did I want to install a solar panel? We stayed in France this winter for 3 weeks, 95% of the time on aires with no electric, and no charges (euro type charges, not electric type charges)...

 

Anyway, just in case anyone is interested.

[colin]

Had a 30w flexible panel on our old T25, was stuck on with (what i'll call) double sided flashbanding, leaving about 50% of panel with 1/8" gap underneath, no problems with overheating,

Would happily use one again.

[aandncaravan]

If your Solar regulator has a LCD display, I would question its suitability for use in a Motorhome?

For reasons of efficiency the regulator needs to be mounted next to the Power distribution box or the Battery, both often in places where the unit can't easily be viewed.

That is why most Motorhome Solar regulators (not the ones described as being for a Motorhome) have no display or readout as they can't be seen in the outside battery box, in the Garage, under the seats, etc.

 

The problem with the ones with a display is that there is a temptation to mount them up near the roof at eye level, which can drop efficiency 50%. See our Solar pages for why : http://www.aandncaravanservices.co.uk/solar-power.php

 

The best option is a regulator fixed where there is minimum voltage drop, with a remote display like a Watt Meter.

 

Flexible panels (and some cheaper fixed ones) tend not to use Glass, but a 'clear' Plastic (that is why they are so much less heavy) which 'clouds' with age. Have you ever seen Perspex after a couple of years in the sun?

This 'clouding' reduces the amount of light that reaches the Silicon Cells, with a big drop off in power output by 3 years.

 

We would suggest that a flexible panel is best used only where it is proposed to be replaced every 2 years and no other option is available.

 

 

[Curtisden]

RE Regulator location I would agree the nearer to the battery the better. But there is another option and that is a separate gauge/meter which is positioned anywhere and is linked to the regulator by a cable to provide data.

i have one and it works very well.

Re lightweight solar plastic panels I also have one of these and while drop off with clouding is IMO not that great they do discolour I am replacing mine after 3 years due to water ingress, something the manufacturer tells me that have never heard of?

 

[aandncaravan]

The data cable versions can be expensive, the digital Watt Meter (about £19 on eBay) we talk of above is a remote display and can be located almost any where.

 

We have not seen a Flexi panel over 3 years old that was still working properly. Having said that we have only seen about 16 flexi panel installations, most we see are rigid style installations.

 

 

 

 

[colin]

aandncaravan - 2015-05-25 2:59 PM

 

 

Flexible panels (and some cheaper fixed ones) tend not to use Glass, but a 'clear' Plastic (that is why they are so much less heavy) which 'clouds' with age. Have you ever seen Perspex after a couple of years in the sun?

This 'clouding' reduces the amount of light that reaches the Silicon Cells, with a big drop off in power output by 3 years.

 

We would suggest that a flexible panel is best used only where it is proposed to be replaced every 2 years and no other option is available.

 

 

The flexible panel was on our for around 10 years with little if any noticeable drop in efficiency.

 

As for output displays, why bother just let the panel get on with the job.

[Charles]

I haven't bothered mounting my panel. I like the fact i can point it directly at the sun & there's no holes to drill in the van. also it's like brand new still. Just bought a digital ammeter module for my home made controller so I can maximize the output.