Solar panels generating power in the dark?

[xterrester] "I am still wondering if solar cells are capable of collecting energy from electromagnetic frequencies other than visible light."

Yes, althought this is very sensitive to the specific design of the cells. IR energy is the most common non-visible EM radiation that can be captured and converted by solar cells, but in theory any frequency of EM energy will work if the cells are designed properly for that frequency.

Most commercially available cells are NOT designed to collect energy from any part of the spectrum except the visible. But this is changing as the cost of extending the frequency response drops.

Looks like there is not really enough information in the article to answer your questions.

LB

<i>xterrester</i>
Here is some information on Larrys message.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Demonstration of Infrared-Photovoltaics for a Full-Spectrum Solar Energy System

(Received 19 May 2004; revised 12 May 2005)
A nonimaging (NI) device and infrared-photovoltaic (IR-PV) array for use in a full-spectrum solar energy system has been designed, built, and tested (Dye et al., 2003, "Optical Design of an Infrared Non-Imaging Device for a Full-Spectrum Solar Energy System," Proceedings of the ASME International Solar Energy Society Conference; Dye and Wood, 2003, Infrared Transmission Efficiency of Refractive and Reflective Non-Imaging Devices for a Full-Spectrum Solar Energy System," Nonimaging Optics: Maximum Efficiency Light Transfer VII, Proc. SPIE, 5185; Fraas et al., 2001, Infrared Photovoltaics for Combined Solar Lighting and Electricity for Buildings," Proceedings of 17th European Photovoltaic Solar Energy Conference). This system was designed to utilize the otherwise wasted infrared (IR) energy that is separated from the visible portion of the solar spectrum before the visible light is harvested. The IR energy will be converted to electricity via a gallium antimonide (GaSb) IR-PV array. The experimental apparatus for the testing of the IR optics and IR-PV performance is described. Array performance data will be presented, along with a comparison between outdoor experimental tests and laboratory flash tests. An analysis of the flow of the infrared energy through the collection system will be presented, and recommendations will be made for improvements. The IR-PV array generated a maximum of 26.7 W, demonstrating a conversion efficiency of the IR energy of 12%. ©2006 American Society of Mechanical

<i>source</i>
scitation.aip.org/getabs/servlet/GetabsS...dtype=cvips&gifs=yes

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thebobgy

Back in high school, I did a science project in which I learned that solar panels are quite effective at absorbing ultraviolet light.

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Astrodelugeologist</i>
<br />Back in high school, I did a science project in which I learned that solar panels are quite effective at absorbing ultraviolet light.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">That is quite interesting. Out of curiosity; when you say "absorbing ultraviolet light" do you mean that the panels were generating electricity based on the ultraviolet light alone without a source of visible light?
thebobgy

I wasn't working in a perfectly dark room. There was a small amount of ambient visible light and, I presume, other forms of electromagnetic radiation. There was a small amount of electricity generated by this ambient light.

I worked by exposing the solar cells to different colors of light, and measuring the amount of electricity being produced <i>in addition</i> to that produced by the ambient light.

When all was said and done, white light worked the best. But all of the colors I used, including infrared and ultraviolet light, produced some amount of current. UV light was actually rather effective, better in fact than some of the colors of visible light. I attributed this to the higher frequency of the UV light. The cells performed the worst under IR light, which I likewise attributed to IR's lower frequency.

Keep in mind that I was only in high school when I did this, though...There were probably many problems in terms of controls and even methodology to some degree. I was a teenager, after all.

--Astro

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Astrodelugeologist</i> 09 Aug 2006 : 00:44
<br />I wasn't working in a perfectly dark room...
I worked by exposing the solar cells to different colors of light, and measuring the amount of electricity being produced <i>in addition</i> to that produced by the ambient light.
Keep in mind that I was only in high school when I did this, though...There were probably many problems in terms of controls and even methodology to some degree. I was a teenager, after all.
--Astro<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Thank you Astro, That must have been a truly fascinating Science class. Your message ties in well with Larry’s earlier message. If as you say, the amount of energy produced was “in addition” to the ambient light then I would conclude that may be possible to generate energy in the absence of visible light. You have inspired me to do some testing on my own. Again, thank you.
thebobgy