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efficiency of infraread cell

efficiency of infraread cell

efficiency of infraread cell

(OP)
What is theoretical efficiency and practical efficiency of infrared photocell.
I know that solar panels operate with efficiency from 5% to something like 35% at best, due to pure response over wide light spectrum.
Does the photocell for infrared radiation only have higher efficiency?
Are there any infrared photocell panel (like solar panels) available?

RE: efficiency of infraread cell

What are you trying to do with these infrared sensors?

TTFN



RE: efficiency of infraread cell

(OP)
I got some idea.
The problem with contemporary solar cell have relatively low efficiency due to narrow range of operation (narrow in terms of wavelength).
All the new design solar panels with high efficiency employ multi layer of sensors that operate in different light wavelength.
Now the question is : what if you convert all light wavelength to one wavelength? Does that approach could lead to higher efficiency eclectic solar panel?

Here is the idea:
Let say we will use only infrared panels. In front of it we will place metal surface painted in black (both sides) so whole spectrum of day light will absorbed. Between the black surface and infrared cell should be gap so radiation is aloud no heat conduction.  
To balance the absorb and transmitted radiation that black surface will have to reach temperature at list 100C (assuming that sun light that reach earth surface have around 1000W per square meter).
One problem is that the black surface will radiate the infrared on both side (to the Sunny side as well as where the infrared panel is place). That mean 50% efficiency (not including the efficiency of infrared panel).
Now what if we discard the infrared that come from the Sun and wanna to recover shorter wavelength (the visible and ultraviolet). I am not sure how big the energy penalty it will hold, but if i am correct the visible light and ultraviolet have pretty high energy density.
Now in order to improve the  efficiency reflective filters have to be employ to hold infrared from escaping in wrong direction (back to the Sun)
The reflective filters are heat control filters.
In this link they call them Hot Mirrors .
http://www.lot-oriel.com/site/pages_pl_pl/products/optical_filters/hot_mirrors.php.

Now is the question what the efficiency of the infrared cells?

 Heat radiation is pretty interesting phenomena. In our environment (at list any temperature that we live) there always heat radiation. The question is can we use it.
1 square meter of black surface radiate almost 453Watts (in theory). If we use some parabolic mirror we could create significant energy potential with out adding any work.
Yes I know that validate second law of thermodynamic.     

RE: efficiency of infraread cell

Sorry, infrared detectors have been around for 40 yrs and every variation has already been tried.

Photon detectors are useless for your application.

Thermal detectors are grossly inefficient for these applications.

TTFN



RE: efficiency of infraread cell

(OP)
I see you miss the point.
I do not looking to invent new infrared detector. As u said that pretty much invented.
The idea is to convert the visible light (that contain many wavelength) to one wavelength and try to use photo cell that is design for that one wavelength. The assumption is that that cell design for one wavelength should have higher efficiency in converting one wavelength then design that try to deal with them all.

RE: efficiency of infraread cell

I didn't miss anything at all.  You misunderstood my answer.

You need to review the existing literature on solar cells.  Silicon is responsive from about 30 nm to 1100 nm.  That accounts for almost half of the solar radiance.  

Converting the visible spectrum into infrared to then convert to electricity is a losing proposition.  

And, as I stated earlier, thermal converters are not particularly efficient to begin with.

TTFN



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