The computer simulation model calculates the US oil consumption every year over the entire 21st century for each alternative vehicle scenario. The results show that hydrogen-powered fuel cell electric vehicles will have to be added to plug-in hybrids and biofuels to achieve energy “quasi-independence,” which we define as meeting all our petroleum needs (including non-transportation uses) from the American hemisphere in a future crisis:

To summarize:

• Business as usual--100% regular gasoline cars: oil consumption rises as more cars travel more miles each year, even though the model assumes increasing fuel economy for regular cars
• Hybrid electric vehicle (HEV) Scenario: converting more and more cars to hybrid electric vehicles reduces oil consumption, but oil use rises slightly again in the last half of the century due to increasing vehicle miles traveled
• Gasoline Plug-in hybrid electric vehicle (PHEV) scenario: plugging-in gasoline HEVs also cuts oil consumption as shown by the orange curve above; by the end of the century, oil use in the light duty passenger (cars and trucks) would stabilize at 30% below 2009 levels
• Biofuel (Cellulosic ethanol) Plug-in hybrid electric vehicle scenario: running the plug-in hybrids on biofuels such as cellulosic ethanol cuts oil use even more, reaching the level that could be supplied by non-OPEC nations (the upper red dashed line in the graph) by 2070
• Fuel cell electric vehicle scenario: adding hydrogen-powered fuel cell electric vehicles to the mix would eliminate nearly all oil consumption from the light duty vehicle mix by the end of the century; fuel cell electric vehicles would also reduce oil use by 2060 to levels that could be supplied exclusively by oil from the American hemisphere

The two secondary scenarios, hydrogen-powered ICE hybrids and battery-powered EVs would achieve approximately the same oil reductions as the FCEV. However, we consider these two secondary scenarios to have a lower probability of success in terms of reaching 98% of the light duty vehicle market (cars and trucks) as assumed in the model.

This computer model assumes that PHEVS enter the marketplace five years before hydrogen-powered FCEVs:

Despite this early lead, the PHEV scenario only reduces oil consumption by 6.3% by 2030, relative to the base case HEV scenario, while the FCEV scenario would cut oil use by 14.7%; thus the hydrogen-powered FCEV scenario cuts oil consumption 2.3 times more than the PHEV scenario:

The hydrogen FCEV scenario cuts more oil consumption since no oil is used in producing hydrogen, while the PHEVs still rely on gasoline for some of their travel.

For the full technical details of our computer simulation results, see the August 2009 International Journal of Hydrogen Energy article. For a detailed description of the input assumptions for these models, see another article published in December of 2009.