Amtrak is experimenting with a bio-diesel fueled train … called the Heartland Flyer.
" … nation’s first-ever test of a cleaner and renewable biodiesel fuel blend to power a daily interstate passenger train between Oklahoma City and Fort Worth … research project … on the daily Heartland Flyer train operated by Amtrak … biodiesel blend includes beef byproduct and is provided by a Texas-based vendor."
" … the biodiesel blend known as B20 (20% pure biofuel and 80% diesel) reduced hydrocarbons and carbon monoxide each by 10 percent, reduced particulates by 15 percent and sulfates by 20 percent. … measurements will be taken … at the end of 12 months so any impact of the biodiesel on valves and gaskets can be measured…."
Via: Amtrak LINK