But once you've got reasonably cheap and plentiful energy, what's the big incentive for growing locally. If trucking it from Kansas to NYC doesn't pollute as mu

But once you've got reasonably cheap and plentiful energy, what's the big incentive for growing locally. If trucking it from Kansas to NYC doesn't pollute as much, reasons for building those towers diminish somewhat. Of course, it's slightly different if you've got plentiful energy, but no good way to transmit/store it. Lots of solar panels all over the city to power its greenhouses. Or windmills in Chicago.