Ancient Pharaohs, Aztecs and others abandoned cities. Expensive business. Global warming promises inundation of many cities. Some cities will be abandoned as new cities appear in dryer places such as Bill Gates' Belmont Arizona.
Refocussing of smart cities from big brother sensing and people control to energy, food and water independence and magnificent free public transport facilitates cities becoming moveable. IDTechEx report, Smart City Opportunities: Infrastructure, Systems, Materials 2019-2029 explains.
Clearly the city needs reinventing. The smart city concept envisages radical improvements in technology that can hugely improve most aspects and even add new delights. A term like smart city gets highjacked by those selling incremental improvements going on anyway. However major changes are key such as several new and planned cities banning private cars and/ or being energy independent using moveable zero emission electricity generation. No more massive, ugly steel and concrete structures with expensive, slow decommissioning such as offshore wind towers, huge river dams and tidal barrages. In come tethered drones - Airborne Wind Energy AWE - tapping higher winds that are stronger and almost continuous, a MW "propeller" under a moored ship or on the sea floor called "tidal stream power" or wave power working even in continuous one meter waves and of course solar plummeting in price below all others but very intermittent. They are all easily transportable and installed in hours. Move the city if you wish.
In addition, the first three are almost continuous, often needing no toxic, short-lived battery, so they are often base power when only a non-toxic, fit-and-forget supercapacitor is inserted. See the IDTechEx report, Wave, Tidal and Hydro Power 1W-10MW 2018-2038. Houses are already on sale with no infrastructure needed because they grab their own water, treat sewage and make their own electricity. Later versions will add the new generators - solar windows, solar/ supercapacitor bodywork and so on. Partly this is triggered by new vulnerability, with national grids taken down by both cyberattacks and poles and wires collapsing from the increasingly violent weather from global warming. Defend against cyberattack and the increasingly violent weather we have unleashed and if necessary, move the sophisticated city. Not so much "roll the covered wagons" as "ship the luxury house".
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