'Smart cities' of the future
Why should I be aware of this?
Smart cities of the future would be self-contained units. Energy for the buildings would come from the powerful weather systems sweeping across their roofs and feeding it down to homes below and vehicles in the streets.
Cars would be electric, and battery charged in garage when enegry supplies are low. Every scrap of waste food, garden trimmings and even sewage would be used to ferment gas.
All about 'smart cities' of the future
With the European Union setting itself the ambitious task of cutting carbon dioxide (CO2) emissions to a fifth below 1990 levels by 2020 - the biggest cuts anywhere in the world – the idea of self-sufficient cities is gaining currency.
"Smart electricity grid"
The system would be centered around a "smart electricity grid" which would allow electricity to flow where it is needed most and dissipate the energy spikes as weather systems sweep through. A smart grid would help stabilize the energy flows, so the more fluctuating energy you have from renewables, the more it makes sense to have a smart grid.
It will be possible to have electric vehicles connected to the grid to store energy at times when too much is produced - and they could feed it back into the grid when there's not enough.
Smart cities would not only gradually reduce energy needs, they would also start producing their own over time. This would bring in an era of breakthroughs and of a technological revolution in the construction sector.
Still a distant dream
Though much of the technology needed is still a distant dream, dmart house concepts are beginning to be practiced in some parts of the world. French construction company Bouygues is working on an office in Meudon, western Paris, which uses 4,000 square meters of solar panels to meet not only its own energy needs but also to export surplus energy back to the power grid.
- The International Energy Agency has estimated that approximately € 500 billion will be invested in European grids by 2030. The deployment of smart grids will play an important role in this. 
- By 2050, North America will need somewhere between 15 and 20 Terawatt hours/year of electric power. 
- The storage, transmission, and distribution technologies of the smart grid of the future—a web-enabled, digitally controlled, intelligent delivery system—must be able to deliver that amount of power to all corners of the continent efficiently. 
- 'Smart cities' are a green vision for the future
- EU cities plan for energy self-sufficiency