Very interesting article from a Californian VC here “Hubbert’s Peak” about when the oil will run out.

Dr. Hubbert (in response to remarks by David Nissen – Exxon): “… [T]here is a different and more fundamental cost that is independent of the monetary price. That is the energy cost of exploration and production. So long as oil is used as a source of energy, when the energy cost of recovering a barrel of oil becomes greater than the energy content of the oil, production will cease no matter what the monetary price may be.” [referenced by Ivanhoe, 1982]

I remember reading about nuclear power stations requiring several years of their energy output just to build them. Wonder if it takes into accounts efficiency