CO2 storage have life-cycle CO2 emissions similar to those of gasoline; with geologic CO2 storage, these fuels have near-zero life-cycle CO2 emissions.

A program to aggressively support first-mover commercial coal-to-liquid and coal-and-biomass-to-liquid fuel production plants with integrated geologic CO2 storage would have to be undertaken immediately if the United States were to produce fuels with greenhouse gas emissions similar to or less than petroleum-based fuels to address energy security in the near term.

Whether thermochemical conversion involves coal alone or coal and biomass combined, the viability of CO2 geologic storage is critical to its commercial implementation. This means that large-scale demonstrations of and the establishment of regulatory procedures for CO2 geologic storage would have to be aggressively pursued in the next few years if thermochemical conversion plants integrated with CCS are to be ready for commercial deployment in 2020 or sooner. If such demonstrations are initiated immediately, and geologic CO2 storage is proven viable and safe by 2015, the first commercial plants could be operational in 2020.

Because plants for the conversion of combined coal and biomass into liquids are much smaller than those that convert coal alone, and because they will probably have to be sited in regions that are close to coal and biomass supplies, build-out rates will be lower than for the cellulosic plants discussed above. The committee estimates that at a 20 percent growth rate until 2035, 2.5 million barrels per day of gasoline equivalent could be produced in combined coal and biomass plants. This would consume about 270 million dry tonnes (300 million dry tons) of biomass per year—thus tapping less than the total projected biomass availability—and about 225 million tonnes of coal.

Given the vast coal resource in the United States, the actual supply of such fuel will be limited by its market penetration rather than feedstock availability. At a build rate of two to three plants per year, in 20 years up to 3 million bbl/d of gasoline equivalent could be produced from about 525 million tonnes of coal each year. However, all costs and social and environmental impacts of the associated level of coal production—an increase of about 50 percent—would have to be considered. At a build out of three plants starting up per year, five to six plants would be under construction at any one time.

Costs, Barriers, and Deployment

The committee estimated the costs of cellulosic ethanol, coal-to-liquid fuels with or without geologic CO2 storage, and coal-and-biomass-to-liquid fuels with or

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