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General => General Forum => Topic started by: NM_Shooter on August 20, 2008, 02:05:23 PM

Title: Intensifiers for solar panels...
Post by: NM_Shooter on August 20, 2008, 02:05:23 PM
A company who is local to ABQ is experimenting with using fresnel lenses to overdrive solar panels in an effort to increase the power per $$$ capability.  I asked one of the engineers there if that would cause early wearout on the panel, and he said no.

I started to wonder how difficult this might be to do ourselves.  I am considering using some polished metal panels to reflect additional sunlight onto the surface of the panel to increase the power output of the panel.

This would work best for an active tracking panel, but would also help (somewhat less optimally) for fixed panels as well.  It would just allow more energy during some parts of the day.

Has anyone experimented with this at all?

Regards,

Frank
Title: Re: Intensifiers for solar panels...
Post by: glenn kangiser on August 20, 2008, 02:11:01 PM
Overheating does cut the charge back on panels and I have also heard that it will damage them to use a fresnel on them ---

Not sure what is true though.
Title: Re: Intensifiers for solar panels...
Post by: MountainDon on August 20, 2008, 04:03:21 PM
I don't know anyone who has experimented with this. Glenn, is correct that as temperature goes up the output vgoes down. There may be a point where the panel temp could cause damage; don't know for sure. The panel can actually get hot enough to cause a burn to skin without any intensification.

The converse is true; cold panels put out more power. Enough so as to possibly cause overvoltage problems on cold winter mornings. That's something that must be considered when placing panels in series.
Title: Re: Intensifiers for solar panels...
Post by: MountainDon on August 20, 2008, 05:31:56 PM
I found what I was looking for...

PV panels can run up to 80 degrees C in bright sun (176 F)
Title: Re: Intensifiers for solar panels...
Post by: NM_Shooter on August 20, 2008, 06:32:07 PM
I seem to recall that they were using a fresnel to effectively double the amount of light striking the panel, and that by doing so they hoped to achieve  $$$ efficiencies in the $1 per watt territory (in volume). 

As you guys know, most PVs don't operate anywhere near optimal conditions for exposure.  For instance, I fiddled with my 53W panel, and was never able to get more than about 36W out of it.  They are non-linear though... and to get maximum power you have to have to impedance match the load.  I think some of the more high tech battery conditioners do this.

I suspect that with a small amount of reflected surface i can boost the output of the panel without endangering it.

I have a cheapie panel at home that I may experiment with just for grins!

-f-
Title: Re: Intensifiers for solar panels...
Post by: MountainDon on August 20, 2008, 06:36:32 PM
I'd think that using a reflector like that could boost output some without running into trouble. Let us know how it works out.  :D
Title: Re: Intensifiers for solar panels...
Post by: Dustin on August 20, 2008, 10:27:37 PM
I know of at least two companies that are working on fresnel lens boosted tracking pv panel systems. They don't use traditional panels. They are very small pv panels made to be used in this way (under high heat conditions), so they don't lose efficiency.

One company:
http://www.greenandgoldenergy.com.au/ (http://www.greenandgoldenergy.com.au/)

Emcore makes the solar panel chips.