Which panel do I buy? (1 Viewer)

[Jammel1980]

I’m currently confused (“not difficult” I hear the wife say)

I have a choice between
140W EFTE flexible panel with a 10a MPPT controller

• Peak power: 140W
• Maximum power voltage: 24.2V
• Maximum power current: 5.79A
• Open circuit voltage: 28.6V
• Short circuit current: 6.25A
• Power allowance range: +/- 5%
• Dimensions: 1445*540*3 mm
• Weight: 3.15 kg

And a

150W polycrystalline flexible panel with a 20a MPPT controller

• 
  
  
  • Peak power: 150W
  • Maximum power voltage: 18.7V
  • Maximum power current: 8.02A
  • Open circuit voltage: 22.54V
  • Short circuit current: 8.41A
  • Dimensions: 1547 x 673 x 2 mm
  • Weight: 3.5 kg

Price is not the issue, more along the lines of what am I going to get the most power out of, obviously I know it all depends on the time of year, weather and the angle of the panels etc, my knowledge on this subject is limited to what I have read and what I have remembered so which one would you choose and why?

 

[vwalan]

i say better to get two smaller ones say 80 or 100 wt . then if you get partly in shade you should still have some power.
plus should stones or anything get dropped from bridges if one gets busted the other keeps working . damage a big panel lose it all.

 

[Jammel1980]

That’s a good idea! Thanks, I’ll probably get 2 panels instead now, which type of panel above would you choose though?
One has a higher maximum power voltage and the other has a higher maximum power current. What’s more important?

Thanks

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[vwalan]

all mine are polycrystal. 3 were secondhand in morocco 15yrs ago then later i put 3 new ones on as well.
the newer ones are slightly more efficent .
i did have some mono crystal before again secondhand , they werent as good as the poly but age might again of been the problem, mind they are still in use on my lads van.
all mine are on an ally frame .
all i can say is these days look on ebay . i find the cheapest work.
mount on ally or plastic angle .
i use simple pwm regulators . they work and seem trouble free .
lots use mppt regs but so long as mine are not causing a problem i shall keep using them.
i do have 6x80wt on the roof . plus a 600amp battery bank . powers house fridge . tv , and twintub when away.
so long as the sun shines all ok .

 

[mitzimad]

its the watts that matter so the second one is better

 

[Jammel1980]

Thanks guys, that’s the cheaper kit as well
So I just brought 2 x 100w flexible panel with a 20a MPPT controller.

Next question will be how to install it

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[two]

The first controller is under-specified because it can only pass 120W (10A x 12V) of the potential 140W available. In practice, this may never happen if staying in UK.

If I had two panels, I’d consider getting two controllers. If one panel gets damaged or shaded, it will affect the performance of any others in its bank. Keeping them completely separate would provide greater resilience and maximize output.

 

[Antique]

Hi @Jammel1980

I've been hanging my nose over a similar set -up. Could you let me know where you sourced the components please ?
Will follow this thread with interest.

Best regards
Antique

 

[Freespirit1]

I’m currently confused (“not difficult” I hear the wife say)

I have a choice between
140W EFTE flexible panel with a 10a MPPT controller

• Peak power: 140W
• Maximum power voltage: 24.2V
• Maximum power current: 5.79A
• Open circuit voltage: 28.6V
• Short circuit current: 6.25A
• Power allowance range: +/- 5%
• Dimensions: 1445*540*3 mm
• Weight: 3.15 kg

And a

150W polycrystalline flexible panel with a 20a MPPT controller

• 
  
  
  • Peak power: 150W
  • Maximum power voltage: 18.7V
  • Maximum power current: 8.02A
  • Open circuit voltage: 22.54V
  • Short circuit current: 8.41A
  • Dimensions: 1547 x 673 x 2 mm
  • Weight: 3.5 kg

Price is not the issue, more along the lines of what am I going to get the most power out of, obviously I know it all depends on the time of year, weather and the angle of the panels etc, my knowledge on this subject is limited to what I have read and what I have remembered so which one would you choose and why?

I don't think there is anything much out there to beat the latest CIGS technology fully flexible Solar Panels from http://www.mipvsolarpanels.co.uk/

I actually bought similar panels to the 140w semi flexible ones you quote and they are for sale unused in classified here if that's your choice.

However - having found the MIPV ones I decided to go with them and am extreamly happy with their performance and ease of fitting - they are particularly suited to the hotter areas of Europe when it comes to the question of heat as the Poly and Monocrystaline loose about 40% of output whereas these loose a very small fraction of that at high temperatures.

They are also extreamly good in low light conditions.

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[DBK]

Flexible panels aren't widely used on MHs. Probably because they are generally much more expensive than the rigid ones. But if you have a smooth flat roof there is no reason not to use them and I would just follow the manufacturer's instructions on how to fit them - they will be stuck down with an adhesive.

 

[Freespirit1]

MIPV panels -3mm thick with Sika specially developed self adhesive - rated at 130 mph winds - 340watt in total but plenty room for more. Aerodynamic- no wind noise - very light 3kg each - 25% more energy yield than best Monocrystaline panels - virtually no reduction in output at very high temperatures. Not the cheapest but you have to pay for quality and performance - however very comparable in price to the best semi flexible Monocrystaline ones on the market.

Totally made in North Wales !!! 5yr. Manufacturers warranty - 10 yr Performance warranty!

 

[two]

However - having found the MIPV ones I decided to go with them and am extreamly happy with their performance and ease of fitting - they are particularly suited to the hotter areas of Europe when it comes to the question of heat as the Poly and Monocrystaline loose about 40% of output whereas these loose a very small fraction of that at high temperatures.

Solar panels are said to loose efficiency when hot, and that does not seem at all unreasonable, but they’re only going to get really hot when there’s plenty of sun and demand for electricity is at its lowest. In winter, when you are likely to need it most, I think the ambient temperature will compensate.

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[Freespirit1]

In winter, when you are likely to need it most, I think the ambient temperature will compensate.

A natural assumption - however these CIGS panels are particularly good at low levels of light / sun at dawn and dusk out performing silicon technology!

 

[Rollin]

A natural assumption - however these CIGS panels are particularly good at low levels of light / sun at dawn and dusk out performing silicon technology!

Love the sound of these freespirit!

Did you fit them yourself?

The cables look a bit exposed to my untrained eye - is there not a risk that winds/slipstream could work them loose, or a low branch could snag them?

 

[Freespirit1]

Love the sound of these freespirit!

What total wattage have you got there, and did you fit them yourself?

The cables look a bit exposed to my untrained eye - is there not a risk that winds/slipstream could work them loose, or a low branch could snag them?

Hi Rollin - I've got one 120 watt and four 55 watt panels up there giving me a total of 340 watt but in reality it's more like 360 as the rated wattage is a minimum that they are rated at and each has a test certificate giving actual which is always a bit over.

Yes I fitted them myself but "fitting" is perhaps a tad too much like work lol.

After cleaning the roof - I literally laid them out in their chosen positions - put a few pencil marks around them - wiped the area that they were to be positioned with the activator/ degreaser provided - then peeled off backing paper like a double sided tape and laid them.

I have wired them in series which gives around a total voltage of 106volts and reduces wiring cable size and volt drop in the lines to the controller (rated at Max 150 volt 600 watt input).

The solar cable is 4mm Solar with MC4 connectors and I have used some simple sticky pad cable saddles you can get from RS (Radio Spares).

Since fitting about 5 weeks ago I've been in very wet, windy, hot, humid you name it conditions travelling about 3k miles to the Canaries and no problems.

The cables are actually higher off the roof at about 6 mm diameter than the panels are at 3mm height.

I don't think I need worry about snagging them with a sat dish and roof lights at probably 100 mm proud of the roof. I might actually put some white roof repair tape over the wires which will hide them! and improve slip stream!

For you marine guys out there you can walk all over these panels constantly without any problem and them have a fairly Matt not slip surface tested for marine applications too!

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[Rollin]

a total of 340 watt but in reality it's more like 360 as the rated wattage is a minimum that they are rated at and each has a test certificate giving actual which is always a bit over.

That makes a refreshing change! I'm still getting to grips with all the different ways that panels lose their stated power before hitting the battery!

 

[Freespirit1]

That makes a refreshing change! I'm still getting to grips with all the different ways that panels lose their stated power before hitting the battery!

Yep - that's why I've ditched the semi- flexible ones from Photonic Universe ( very good monocrystaline) but not up to the MIPV.

There's somewhat of an issue with semi- flexible poly or monocrystaline as well I suppose in as much as crystal as the name implies " will not Bend" and although those panels can bend slightly they are subject to very fine hairline cracks in the crystal that you can't see with the naked eye.

The Mipv ones I have can be bent to a minimum radius of 275 mm and come rolled up in a 450mm square box.