A typical quarter section (160 acre) center pivot covers 128 to 132 acres leaving 4 "wasted corners" covering between 28 to 32 acres available for solar.
So supposedly such a center pivot is then 1/4 mile long. Wouldn't that then be a center pivot that's 1320' long? I think they're using a smaller setup here, but they're not exactly clear about that.
Edit: searching around, that sounds like a 10 tower. The article said they've got a 7. So I think they've got a lot more than I initially guessed and slightly less than your post guessed.
