HEALTH COSTS OF AIR EMISSIONS

Climate change and health costs of air emissions from biofuels and gasoline
Jason Hill,Stephen Polasky,Erik Nelson,David Tilman,Hong Huo,Lindsay Ludwig,James Neumann,Haochi Zheng and Diego Bonta

Abstract

Environmental impacts of energy use can impose large costs on society. We quantify and monetize the life-cycle climate-change and health effects of greenhouse gas(CHG) and fine particulate (PM2.5) emissions from gasoline ,corn ethanol,and cellulosic ethanol. For each billion ethanol-equivalent gallons of fuel produced and combusted in US,the combined climate-change and health costs are $469 million for gasoline ,$472-952 million for corn ethanol depending on biorefinery heat source(natural gas,corn stover,or coal) and technology,but only $123-208 million for cellulosic ethanol depending on feedstock(prairie biomass,Miscanthus,corn stover,or switchgrass). Moreover,a geographically explicit life-cycle analysis that tracks PM2.5 emissions and exposure relative to US population shows regional shifts in health costs dependent on fuel production systems. Because cellulosic ethanol can offer health benefits from PM2.5 reduction that are of comparable importance to its climate-change benefits from GHG reduction,a shift from gasoline to cellulosic ethanol has greater advantages than previously recognized. These advantages are critically dependent on the source of land used to produce biomass for fuels,on the magnitude of any indirect land use that may result,and on other as yet unmeasured environmental impacts of biofuels.

Proceedings of the National Academy of Sciences of the United States of America ,February 2,
2009