一辆车的一生：
100,000miles/(20mile/gallon) = 5,000 gallon gas ~ 21,000 gallon crude oil ~500 barrels of crude oil. （已经相当保守）
>600,000,000 passenger cars travel the streets and roads of the world today.
>50,000,000 new cars produced every year.
Oil needed for next 20 years only:
6E8 x 500/2 = 1.5E11 barrels for current cars （现车算一半油需）
5E7 x 20年x (1.05^20) x500 ~ 1.35 E12 barrels for new cars (5% growth annually)
So, ~ 1.5E12 barrels are needed for all cars produced before 2031.
Total oil reserve is 1.24E12 in 2010 (http://en.wikipedia.org/wiki/Oil_reserves)
（不是所有原油能有效开采，只有部分原油有较高汽油转化率）
结论：如果现行能源架构不发生根本变化，新能源汽车不能有效推出，考虑到美元贬值，十年内油价到上$300绝非危言耸听, 这辈子见到$500/桶油不见得是长寿！
