Report considers the impact of dedicated energy crop production
In early January, the USDA Economic Research Service published a report, titled “Dedicated Energy Crops and Competition for Agricultural Land,” that examines three policy scenarios that could create a market for bioelectricity using dedicated energy crops. The scenarios include a subsidy for bioelectricity generation, a national renewable portfolio standard (RPS) and a national cap-and-trade policy to limit carbon dioxide emissions.
Within the report the ERS explains that dedicated energy crops, such as switchgrass, are viewed as potential renewable feedstocks for both liquid fuels and bioelectricity in the U.S. Markets, however, do not currently exist for large-scale use of the resource.
According to the report, each scenario provides 250 terawatt-hours (TWh) of electricity generation from switchgrass and approximately 50 TWh from forest residue.
The research shows a policy that provides incentives for 250 TWh of electricity generation per year from switchgrass would require approximately 25-29 million acres of land in 2030. In comparison, the report shows approximately 33 million acres of cropland is currently used to grow corn used in ethanol production. Generation of 250 TWh of electricity from switchgrass along with 50 TWh from forest residue would require 234 million short tons of dry biomass in 2030.
According to the ERS, modeling suggests switchgrass production, as a share of total crop land, would be highest in Appalachia, the Southeast and the Northern Plains. On an acreage basis, the results show 11.1 million acreas in the Northern Plains, 8.6 million acres in Appalachia, 4.2 million acres in the Corn Belt, and 3 million acres in the Southeast.
The report indicates switchgrass cultivation, when coupled with reduced acreage for nonenergy crops, would reduce soil erosion by 5 percent nationally, 17 percent in Appalachia, 12 percent in the Southeast, and 9 percent in the Northern Plains. In addition, the amount of nitrogen lost to water would decline by approximately 4 percent when compared to the reference case.
According to the results of the analysis, a national RPS could reduce emissions by 10 percent. Cap-and-trade was shown to decrease emission by 40 percent, but increase the price of electricity by 55 percent. Alternatively, a bioelectricity subsidy could reduce emissions by 1.2 percent, with the price of electricity declining by 0.5 percent.
A full copy of the report can be downloaded from the USDA ERS website.