Oh, you were serious about using solar. If the device gets structually attached or anchored, then it falls under the NEC.
Walus, I understand you concern of safety. What I am saying is you have a choice of GFCI protection or not. If you are really concern, you can put a lockable cover like a weatherproof while in use cover and put a paddle lock on it if you do not want to use a GFCI device and prevent others to use it. If you are installing for some one else. Tell them the pros and cons and let them decide.