Via:41 Fast And Clever Backyard Upgrades You Should Do Now - livingino.com Further info: Rejuvenating solar garden lights — with nail polish! | blog.kriegsman.org
That actually makes sense. An Indian kid came up with a coating for solar cells a few years ago, that not only makes a clear coat, but also domed the cell slightly, this helped focus the incoming light. The end result was a higher efficiency for fixed location solar panels.