Thread: I-V characteristic solar cells - light source related questions...

Hello, everyone!!! My name is Niko, researcher in the field of renewable energy sources (solar cells). At this point of my research, I am in the process of setting up I-V characterization system for DSSCs. The only part of the system I don't have is a light source. Since my residual budget is limited (approx. 500$) I am forced to assemble laboratory made light source. My idea is to purchase xenon lamp with wide range of wavelengths, connectable to regular power line, and use it as a light source. However, I am not familiar with methods of measuring light output power (necessary parameter for solar efficiency calculations), spectral response and the uniformity of output power over illuminated area of interest. So, I would appreciate if any of you could share its own experiences on this subject, suggest a method, or correct if something is overlooked.

Thanks in advance!!!

Originally Posted by Niko

Hello, everyone!!! My name is Niko, researcher in the field of renewable energy sources (solar cells). At this point of my research, I am in the process of setting up I-V characterization system for DSSCs. The only part of the system I don't have is a light source. Since my residual budget is limited (approx. 500$) I am forced to assemble laboratory made light source. My idea is to purchase xenon lamp with wide range of wavelengths, connectable to regular power line, and use it as a light source. However, I am not familiar with methods of measuring light output power (necessary parameter for solar efficiency calculations), spectral response and the uniformity of output power over illuminated area of interest. So, I would appreciate if any of you could share its own experiences on this subject, suggest a method, or correct if something is overlooked.

Thanks in advance!!!

If you're trying to measure things like its spectral response, you need a monochromator. On your limited budget, you'll be forced to build your own (or find an inexpensive one on the surplus market). A xenon arc lamp provides a fairly flat output over the octave range spanning 400-800nm, so your choice is a good one. A diffraction grating and a collimator will be the only additional bits you need to build the source. As an undergraduate many years ago, I used a simple replica grating and a bundle of drinking straws (inspired by a design found in volume 1 of the old SEEC series of books). It worked surprisingly well. Using a cheap tungsten bub (automobile brake light, if memory serves) as a source, measuring the bandgap of silicon was straightforward.

The bigger challenge, frankly, is calibration. What are your accuracy requirements?

ETA: Oh, and welcome to the Forum!