Some relevant facts:
- Oil is the primary energy source in developed countries. The percentage of power to developed countries supplied by oil is 40%.
- Discoveries of new oil sites peaked in 1962 and have been declining rather dismally since then. They are now at one fourth of that peak, and are approaching levels comparable to oil discoveries in the 1920s.
- The amount of oil consumed every year is four times the amount of oil discovered every year.
- Energy resources must produce more energy than they consume, otherwise they are called "sinks" (this is known as the "net energy" principle). About 735 joules of energy is required to lift 15 kg of oil 5 meters out of the ground just to overcome gravity -- and the higher the lift, the greater the energy requirements. The most concentrated and most accessible oil is produced first; thereafter, more and more energy is required to find and produce oil. At some point, more energy is spent finding and producing oil than the energy recovered.
- In 1995, Petroconsultants (now known as IHS Energy Group), the world's leading provider of data and analysis for oil exploration and production, published a report for oil industry insiders titled "World Oil Supply 1930-2050" which concluded that world oil production could peak as soon as the year 2000 and decline to half that level by 2025. Large and permanent increases in oil prices were predicted after the year 2000.
Now, the general conclusion is that oil extraction will peak around 2009, and by 2030-2050 will have completely ceased.
Alternative energy sources will not suffice. Many are in rather small quantities as it is, so would deplete rapidly as well. Others are impractical as is (solar power produces 100 watts per square meter of paneling exposed to bright sunlight, enough to power one lightbulb). Hydroelectric, wind, hydrogen, natural gas, etc. show some potential, but there may not enough time to implement these before lack of oil reduces the overall power available, and hence the power available with which to implement these other power sources is itself substantially reduced. Nuclear power, if used on the scale that oil is now, would create huge amounts of radioactive waste, and the time issue applies to nuclear as well. Coal, which does work fairly well as an emergency option to switch to, is a huge pollutant and with coal it is difficult to regulate energy output.
There is currently no viable, complete alternative to oil, and while an acceptable solution is possible (likely?), if starting now consumption is reduced substantially while changing the energy infrastructure, the real problem is the fact that it's not acknowledged as a definite immediate issue (global warming has nothing on this) so it's going practically unaddressed to the public. The implications of this on our economy and lifestyle are unpredictable, but at worst this can even lead to one of sundry scenarios of global chaos and a threat to civilization itself.
For more, I suggest http://www.gulland.ca/depletion/depletion.htm, which has some further links of its own. There are many books, but without reading them in full The End of Oil by Paul Roberts ($26.00, Houghton Mifflin 2004 0618239774) is very good and Out of Gas by David Goostein ($21.95, W. W. Norton 2004 0393058573), makes a good brief summary.