American drivers notice soaring gas prices. But another fuel – diesel – is also on the rise, and at a much faster pace.

In the U.S., Diesel has mostly been more expensive than gasoline for nearly twenty years. The price gap came about as new rules for cleaner diesel took effect in 2006, as refineries had to run extra ...

A young man filling his vehicle with diesel fuel - Joe Raedle/Getty Images It's rare to pull into any U.S. gas station to find the price per gallon on the diesel pump anywhere near the price of ...