Ubiquitous PV

Ubiquitous PV here refers to the expected easily-applied, durable and very cheap photovoltaic  surface coatings, (perhaps based on solar cells dye-sensitised solar cell solar cells http://www.adciv.org/upload/thumb/4/4d/Wikipedia_logo.jpg/11px-Wikipedia_logo.jpg technology), that could end up covering most roofs, pavements and roads. This vast distributed energy gathering area has the possibility of providing a significant percentage of the energy requirement of modern society.

Conveniently it would mean that the greater the population concentration in any particular area, the greater the energy generating surface would be.