In an article in the Atlantic I was reading the other day, a crazy statistic caught my eye:

The Saudis burn about a quarter of the oil they produce—and their domestic consumption has been rising at an alarming 7 percent a year, nearly three times the rate of population growth. According to a widely read December 2011 report by Chatham House, a British think tank, if this trend continues, domestic consumption could eat into Saudi oil exports by 2021 and render the kingdom a net oil importer by 2038.
http://www.theatlantic.com/magazine/...energy/395315/