New car labels offer QR codes but no grades  EPA, Transportation
Department unveil car labels for comparing efficiency, cost, and
environmental impact among different drive trains, but they drop
letter grade system that automakers balked at.     Each new
label differs slightly depending on the car's drive train or
fuel source. (Click for a PDF of all labels.) Labels in the set
include those for gas, flex-fuel gas-ethanol blends, compressed
natural gas, diesel, hydrogen fuel cell, electric, hybrids, and
plug-in hybrids.  All labels supply the usual combined
city/highway mileage average as well city and highway mileage
separately. But now the label also includes the number of
gallons burned per 100 miles. It gives an estimated annual fuel
cost for the car, and indicates how that compares to the cost of
fueling an average car in that class. It tells you the average
miles per gallon range for cars in that class, as well as the
best MPG achieved by a car in that class.  For alternative-fuel
vehicles, an MPGe (mile