follow one of two scenarios. The first tracks the maximum capacity build experienced with grain ethanol (about a 25 percent yearly increase in capacity over a 6-year period); the second scenario is an aggressive capacity build rate that is approximately twice that achieved for grain ethanol. The two scenarios project 7–12 billion gallons of cellulosic ethanol per year (about 0.3–0.5 million barrels of gasoline equivalent per day) by 2020. Continued aggressive capacity build could conceivably achieve the Renewable Fuel Standard’s8 mandated capacity of 16 billion gallons of cellulosic ethanol per year by 2022, but this would be a stretch. Continued aggressive capacity build could yield 30 billion gallons of cellulosic ethanol per year by 2030 and up to 40 billion gallons per year of cellulosic ethanol by 2035. The latter would consume about 440 million dry tons of biomass annually and replace 1.7 million barrels per day of petroleum-based fuels.

Coal-to-Liquid Fuels with CCS

If commercial demonstrations of coal-to-liquids fuel production with CCS were begun immediately and CCS were proven viable and safe by 2015, commercial plants could be starting up before 2020. The subsequent growth rate could be about two to three plants per year. This scenario would reduce dependence on imported oil, but it would not reduce CO2 emissions from transportation. At a build-out rate of two plants (at 50,000 bbl/d of fuel) per year, 2 million bbl/d of liquid fuels would be produced from 390 tons of coal annually by 2035, at a cost of about $200 billion. At a build-out rate of three plants per year, 3 million bbl/d of liquid fuels would be produced from 580 million tons of coal each year. The latter case would replace approximately one-third of the current U.S. oil use in light-duty transportation and increase U.S. coal production by 50 percent. At a build-out rate of three plants starting up per year, five to six plants would be under construction at any one time.

Coal-and-Biomass-to-Liquid Fuels

The technology for co-fed biomass and coal plants is close to being developed, and several commercial plants without CCS have in fact started to co-feed bio-

8

The Renewable Fuel Standard (RFS) was created by the 2005 U.S. Energy Policy Act; the Energy Independence and Security Act of 2007 amended RFS to set forth “a phase-in for renewable fuel volumes beginning with 9 billion gallons in 2008 and ending at 36 billion gallons in 2022.” The 36 billion gallons would include 16 billion gallons of cellulosic ethanol.



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