The computer simulation model estimates the societal costs (the so-called externality costs) due to:

• Greenhouse Gas Pollution
• Oil imports
• Urban air pollution

The total societal costs are enormous... reaching over $300 billion to $500 billion per year as shown in the following graph.  Adding hydrogen-powered fuel cell electric vehicles to plug-ins and biofuels saves $340 billion per year compared to the gasoline HEV base case.

The annual societal costs for the US for each scenario follow the same trends as each of the three societal ills (greenhouse gases, oil consumption and urban air pollution:

• Business-as-usual: 100% gasoline cars: the total societal costs increase steadily over the century, reaching over $510 billion each year
• Gasoline hybrid electric vehicle base case scenario: adding hybrids does slow the growth of societal costs, but they still reach over $360 billion by 2100
• Gasoline plug-in hybrid scenario: plugging in HEVs cuts the societal costs to $230 billion per year, or a savings of $130 billion compared to the base case HEV scenario
• Biofuel plug-in hybrid electric vehicle scenario: Adding biofuels like cellulosic ethanol to the mix reduces societal costs to $150 billion by the end of the century, saving $210 billion annually
• Fuel cell electric vehicle scenario: total societal costs would fall to “only” $30 billion per year by the 2080 time period with the fuel cell electric vehicle scenario, or an annual savings of $330 billion by 2100 (the BEV and hydrogen ICE HEV scenarios would have similar savings)

The costs of these pollutants were derived by averaging multiple estimates from the literature. Some were based on estimates of the health costs of the pollutants; others were based on the cost of implementing corrective measures to eliminate or reduce the pollution. The net average pollution costs for each pollutant were as follows:

The derivation of these pollution and crude oil import costs (including an estimate of the military costs of protecting our lifeline to Middle East oil) is included in a paper published in the International Journal of Hydrogen Energy in December 2009.