Gasoline-powered internal combustion engines (ICEs) on motor vehicles have become much more efficient and cleaner-burning over the last century. But with more cars on the road, each traveling farther every year, oil consumption and pollution continue to rise.

As the populations of developing nations such as China and India aspire to greater mobility, the planet’s ability to supply sufficient fossil fuels and to absorb the greenhouse gas and urban air pollution will become severely strained.

In the United States, the transportation sector accounts for:

• 28% of all greenhouse gas emissions
• 68% of all oil consumption
• Between 36% and 78% of all urban air pollution

If we are to curb pollution and enhance energy security, we must begin the transition away from nearly total dependence on petroleum for the transportation sector.

Another example of evolving societal threats: rapidly rising consumption of coal in China and to a lesser degree in India threatens huge increases in greenhouse gas emissions:

BP Gulf of Mexico Disaster: Deepwater Horizon explostion & Fire April 22, 2010: