Only like what, 20 years they say?
There's several different estimates.
The problem is the useage of oil is still on an exponential (very high) increase in the US. The production is a so-called "bell-shaped" curve. It accends, reachs a peak and then decends. It's like a hill. The top of the hill (according to the most recent estimate) is Thanksgiving of
this year. From then on (again, according to this estimate), petrolium production is all down hill.
Unless we do something, we're going to have a massive problem.
Whether or not the estimate I've described above is accurate or not, this WILL be a problem we'll have to face in our lifetime.
