Solar panels simply suck.
For those wanting more of a technical detail as to the short-comings of current solar-cell technology, let me start by posting the fact that from what I can find related to current solar cell technology, the highest efficiency is listed as 44.7%. To quote one often cited claim:
“German Fraunhofer Institute for Solar Energy Systems, Soitec, CEA-Leti and the Helmholtz Center Berlin announced today that they have achieved a new world record for the conversion of sunlight into electricity using a new solar cell structure with four solar subcells. Surpassing competition after only over three years of research, and entering the roadmap at world class level, a new record efficiency of 44.7% was measured at a concentration of 297 suns. This indicates that 44.7% of the solar spectrum’s energy, from ultraviolet through to the infrared, is converted into electrical energy. This is a major step towards reducing further the costs of solar electricity and continues to pave the way to the 50% efficiency roadmap. “
Read more at: http://phys.org/news/2013-09-world-solar-cell-efficiency.html#jCp
The problem is that most commercial solar cells in use and available fall short of this mark, by a huge degree from what I have read and been told. Imagine only around an 18% to 23% efficiency.
Most tech can work with this even given the low efficiency except for one major category: illumination. This is where the solar panels suck factor enters into the conversation. Solar powered light are dim, weak and sadly a joke.
Still, with that said, I found one that works rather well if you do not mind spending a few extra dollars.
When I first purchased these, they were $66 each. I tested one and was so please with the output, I purchased another. Even given the harsh bright-white output of these, I am still considering replacing four halogen-based landscaping lights with four of these.
Still, after two years of use, a big problem developed. One that I did not know anything about when it comes to solar panels oxidation.
UV radiation will cause the protective covering of solar cells to break down and turn cloudy. This, in turn, will cause the solar cells efficiency to drop even more and mot be able to recharge the batteries the lights use at night.
I have contacted the manufacturer of the lights and read several blogs and articles about how to recondition and restore the solar panels. This included anything from toothbrush and toothpaste as a polishing abrasive to emery cloth and oil. I decided to try a different product based upon the oxidation of a similar plastic used in a major product most of us use every day, or rather every night: headlights.
I picked up a Rain-X Headlight Restoration Kit at a local Advanced Auto.
I started with the older and heavily oxidated solar light and was amazed at the results. Unfortunately, I did not take any before and after pictured of this solar light. Fort the sake of this blog, I did take pictures of the second solar light I reconditioned.
Yes, that is my reflection on the solar cell. This is after waiting a few minutes for the final sealant to dry. I do not know how long this finish will realistically last.
The current wisdom appear to be that an automotive UV polish or similar protective substance should be applied twice a year.
I’ll have to test that out over the summer.