Whilst I think its a good idea its going to be nearly obligatory to grow your own if you want to have access to fresh fruit and veg in the near future.
I don't think it can solve several key issues.
1) you are never going to be able to sustain any city of significant size (and with mega-cities, its just not possible) in terms of food with food grown in or immediately adjacent to the city. In order (and we see this as far back as 1st cent bc rome) to sustain a large urban population your just going to have to rely to a large extent on large monoculture farming and the necessary logistics to get this into the city.
2) I don't see how this can be applied likewise in a city setting for potable water
3) again with energy
Why 1-3, just can't get the economies of scale you need to produce these in the numbers a large urban environment requires, within that urban environment.