In 2007, the U.S. Congress mandated the blending of biofuels such as corn-based ethanol into gasoline. One of the top goals: reducing greenhouse gas emissions. But today, the nation´s ethanol plants produce more than double the climate-damaging pollution, per gallon of fuel production capacity, than the nation´s oil refineries, according to a Reuters analysis of federal data. The average ethanol plant chuffed out 1,187 metric tons of carbon emissions per million gallons of fuel capacity in 2020, the latest year data is available. The average oil refinery, by contrast, produced 533 metric tons of carbon. The ethanol plants´ high emissions...