From the looks of the area it is intended for, trees would make much more sense. These would only be temporary, trees could last forever as they self-replicate.
Anyway, what they do not provide is shade. How fast does the water need to be harvested so as not to evaporate as fast as it is collected. I would guess there is an enclosed container. It would
be nice to know a lot more about how it works. Perhaps they could redesigned to act as a tree starter with the tree growing from/through the centre. The unit would act as a waterer as well as
fence. The farmer they showed on their page would benefit from trees and new farming practices more than a bit of water. This tower could act as a starting point for that as part of a system towards perma/polyculture.