Cannot comment on cleanliness or warmth when asked, but solar charging is possible. Put this on a backup power supply I made to power the electronics off a large deep cycle battery. My biggest gripe is with the menus and instructions. Tells you which buttons are which, but doesn't explain what the context menu options are, so try and fail to some extent with all settings. It appears to be solar powered so I think if you don't mind making adjustments this is a cheap option. I would recommend other brands that are in the same price range, do the same job and are much easier to use.
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