closure, and legal procedures needed to support the broad-scale application of the technology and would provide the needed engineering data and other information to determine the full costs of geologic storage of CO2.

COSTS, CO2EMISSIONS, AND SUPPLY

This section compares the life-cycle costs, CO2 emissions,5 and potential supplies of the alternative liquid fuel options for technologies deployable by 2020. The result of its analyses is a supply curve of fuels that use biomass, coal, or combined biomass and coal as feedstocks.

It should be noted that the supply curve does not represent the actual amounts of fuels that would be commercially available in 2020. Those supplies could well be smaller because of critical lags—both in the decisions to construct new conversion plants and in the construction itself—as discussed in the deployment section that follows. In addition, some of the coal and biomass supplies that appear to be economical might not be made available for conversion to alternative fuels because of logistical, infrastructural, and organizational issues or because they have already been committed to electric power plants. The analyses show how the potential supply curve might change with alternative carbon dioxide prices and alternative capital costs.

As mentioned earlier, the committee worked with several research groups to develop the costs and CO2 emissions of the individual conversion technologies and the cost of biomass. The analyses presented in this section use those inputs to derive life-cycle costs and CO2 emissions for the alternative fuels.

To examine the potential supply of liquid transportation fuels from non-petroleum sources, the committee developed estimates of the unit costs and quantities of various biomass sources that could be made available. The committee’s analysis was based on use of land that is currently not used for growing foods, although the committee cannot ensure that this land would not be used for food production in the future. The estimates of biomass supply were combined with estimates of supply of corn grain to satisfy the current legislative requirement to produce 15 billion gallons of ethanol per year. The analysis allowed the estimation

5

This section only assesses CO2 emissions because the committee was unable to determine changes in other greenhouse gases throughout the life cycle of fuel production. Such changes, however, are likely to be small.



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