The decoupling of fossil fuels from growth in economic activity has been proceeding rapidly for most of the 21st century and is analysed globally in terms of structures and technologies for energy efficiency and for switching to renewable energy in the world's cities. This is leading to the decline of coal and oil. The evidence suggests that the changes are based on demand for the structures and technologies that are emerging, facilitating a disruptive process. The rise of renewable cities can therefore be expected to accelerate.