DBK [RE-wrenches]

[Marco Mangelsdorf]

Thanks, Peter.  Yes, I do understand that light has both a particle and wave
nature.  What sounds hokey to me is to claim, as the DBK folks do, that a
photon can have a wavelength.  Kinda like saying, if limburger cheese could
have holes, then it would be Swiss cheese.  The question: can a photon have
a wavelength?

Marco
ProVision

-----Original Message-----
From: Peter Parrish [mailto:peter.parrish at calsolareng.com] 
Sent: Sunday, June 11, 2006 11:38 AM
To: RE-wrenches at topica.com
Subject: RE: DBK [RE-wrenches]


Let's be careful here. 

I am a physicist and I have to tell you that light exhibits both a
corpuscular nature (the photon) and a wave nature. This is one of the
fundamental consequences of quantum mechanics.

Having said that, the radiation from the Sun that reaches the earth's
surface can be characterized as a "spectrum" (roughly speaking a curve of
flux over wavelength). 

I am not sure what the total flux (watts per square meter) is over all
wavelengths, but the sun's spectrum peaks in the visible (and less
consequently in the ultraviolet and less in the infrared.

Single crystal or polycrystalline silicon solar cells have their peak
efficiency in the infrared at 1.1 microns, so much of the sun's spectrum is
not utilized. Multiple junction solar cells are tuned to work at different
wavelengths to address this problem.

What we are talking about here is factors of five or ten (20% efficiency or
10% efficiency) not factors of 100.  

As far as electrons are concerned, the ones that can produce net (i.e.
useful external) current are created by photons that get into the
semiconductor junction. That is, they are "born in the junction". Whether or
not, once born, they make it to the external terminals of the solar sell and
become useful current, it another matter and part of the efficiency
equation.

I hope this helps to clarify some of the issues.

- Peter Parrish

-----Original Message-----
From: Marco Mangelsdorf [mailto:marco at pvthawaii.com] 
Sent: Saturday, June 10, 2006 10:18 AM
To: RE-wrenches at topica.com
Subject: DBK [RE-wrenches]



Check this out from the DBK website:

 

ABOUT THE JIL-3000

 The current pictures reflect the prototype version of the new model
JIL-3000. In the manufactured version all cells will be recessed and the
surface will be smooth. 

 Question: How do you get so much power from a solar panel?

 Answer: We have overcome three major obstacles of typical solar panel on
the market: 1) photons which have too short a wavelength bounce off and are
not absorbed; 2) those with too long a wavelength go thru the panel and end
up as heat; 3) and lastly electrons that sit on the skin and fail to go thru
the junction. 

 

Now, I'm not a physicist, but I didn't know that photons possessed
wavelength.Has the nature of light changed that much since I was in college?

 

 

Marco Mangelsdorf

ProVision Technologies, Inc.

Electrical Contractor C-26351

69 Railroad Avenue, A-7

Hilo, Hawai'i 96720

(808) 969-3281

(808) 934-7462 fax

 <http://www.provisiontechnologies.com> www.provisiontechnologies.com

 


[Non-text portions of this message have been removed]


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