ABSTRACT
In a historical perspective we live in a very special time. This is the fossil era where humanity is consuming Earth’s vast resources of oil, gas and coal. The consumption and depletion of this energy treasure only happens once. Cheap and easily available fossil fuels made the agricultural green revolution possible, which again led to an enormous growth in the world population from 1 billion in 1800 to 7 billion today. The population growth and unsustainable development paths have lead to an explosion in the consumption of resources and energy. But we live on a finite planet; unlimited economic growth is not possible and resource limitations will sooner or later halt the growth.
