The researchers said current biofuels produced from crops require an increase in crop production, which has its own severe environmental costs. However, second-generation biofuels, such as cellulosic ethanol derived from processed urban waste, might offer dramatic emissions savings without the environmental catch.
"Our results suggest that fuel from processed waste biomass, such as paper and cardboard, is a promising clean energy solution," said Associate Professor Hugh Tan of the National University of Singapore. "If developed fully this biofuel could simultaneously meet part of the world's energy needs, while also combating carbon emissions and fossil fuel dependency."
The team found 82.93 billion liters of cellulosic ethanol could be produced from the world's landfill waste and by substituting gasoline with the resulting biofuel, global carbon emissions could be cut by figures ranging from 29.2 percent to 86.1 percent for every unit of energy produced.
The study that included researchers from the Swiss Federal Institute of Technology in Zurich appears in the journal Global Change Biology: Bioenergy.