Credible models show that by the end of this century, essentially all of the fossil fuels on earth will be consumed—oil, natural gas, and coal.  Consider the following world model for all fossil fuels:

2009-06-26 Nelder Chart 1

Source: “Olduvai Revisited 2008,” The Oil Drum, by Luís de Sousa and Euan Mearns. Cumulative peak is Data sources: Jean Laherrère for natural gas, Energy Watch Group for coal and The Oil Drum for oil.

By the end of this century – a mere 90 years from now – we must have an energy infrastructure powered exclusively by sustainable and renewable sources.