text: In industry parlance, the boundaries of the solar generator project would be the fence around the array - even though some of that space is grass or dirt, it is legally part of the generating facility, and is handled that way by NFPA and IEEE codes.
  
  With that in mind, I'd recommend making the landuse=industrial area the same geometry as the fence around the array, with a single object having the landuse and barrier=fence tags.