The Minnesota Senate takes up Gov. Tim Pawlenty's proposal Monday to raise the ethanol levels in Minnesota's fuel supply from 10 to 20 percent by 2012. The ethanol debate is multi-faceted, pitting farmers against car makers and environmentalists--who disagree about the net environmental impact of ethanol production--against each other. Taking everything into account, from reduced emissions and domestic energy cultivation to market distortions and voided vehicle warranties, is more ethanol a good idea?