The paper first outlines the challenges the global energy system is facing. It then summarises the present knowledge of energy efficient solutions in all energy using sectors from primary energy to useful energy and, more importantly, from useful energy to energy services (material efficiency...

In the second half of the 20th century we got better at extracting the earth's resources. Much better. So much better in fact, that for 40 years, despite demand for natural resources growing, the cost of those resources decreased. Not anymore. Since 2000, prices for the world's natural resources...