In the long run, an economy that utilizes petroleum as a primary energy source is not sustainable, because the amount of oil in the Earth’s crust is finite. However, sustainability is a misleading concept, a chimera. No technology since the birth of civilization has been sustainable. All have been replaced as people devised better and more efficient technologies. The history of energy use is largely one of substitution. In the 19th century, the world’s primary energy source was wood. Around 1890, wood was replaced by coal. Coal remained the world’s largest source of energy until the 1960s when it was replaced by oil. We have only just entered the petroleum age.31
"Without innovation, no technology is sustainable."
How long will it last? No one can predict the future, but the world contains enough petroleum resources to last at least until the year 2100. This is so far in the future that it would be ludicrous for us to try to anticipate what energy sources our descendants will utilize. Over the next several decades the world likely will continue to see short-term spikes in the price of oil, but these will be caused by political instability and market interference — not by an irreversible decline in supply.
It would appear that the short to medium term problems of energy production are caused by political considerations. Much of the planet's petroleum reserves are controlled by less than stable political regimes i.e. Middle East, Asian and Latin American . This is not, however an issue of supply. Even with regard to reserves under control of the United States the disproportionate power of Marxist inspired "environmental" groups will continue to result in global and national shortages. Look for $100.00/barrel crude oil in the not too distant future.