Peak oil is the point in time when global oil production reaches its maximum and enters into a permanent decline. The Peak Oil year of United States was 1970. It was accurately predicted by M. King Hubbert in 1956. According to Hubbert peak theory, the rate of oil production in any region tends to follow a bell-shaped curve. 

While the peak oil year for the world as a whole is a matter of intense debate, there have been numerous predictions over the years. The two variables that make the peak oil year tough to estimate is demand for oil (effected by population growth and economic development of countries like India and China) and technological advances. For instance, Canada has the world's largest deposits of oil sands. Not all of it is accessible however. But technological advances increase the amount under human reach year after year. 

Nevertheless, the predictions continue to roll out. A recent study by a German Military Think Tank leaked to the internet states that there is "some probability that peak oil will occur around the year 2010." If peak oil is in fact imminent, there will be very serious economic consequences - one other reason to support renewable energy. 

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