Italian architects have dreamed up a "Vertical City." The building has 180 floors and it is anchored to the bottom of the sea. Vertical City would create its own energy. It is covered in photovoltaic glass, which generates electricity, making Vertical City energy independent.
It's designed for optimal air and light circulation, so people can grow gardens throughout the tower. Vertical City is only a sketch for now, but it's designers hope it can provide the blueprint for future sustainable cities.