'Biofuels' is a broad term that includes the lowest technology, older fuels as well as some of the newest, highest tech fuels.  In contrast to "fossil fuels" that were created millions of years ago, biofuels are "contemporary" materials such as wood, charcoal, and crop and animal waste, all of which are in wide use today throughout the developing world, where they expose their users to highly elevated levels of indoor air pollution, and lead to hundreds of thousands of excess illnesses and deaths each year. In advanced societies, older biofuels, such as wood, have maintained a toe-hold in space heating applications, but the newer biofuels are used primarily in the transportation sector.
Read more
(The success of the biodiesel fuel industry relies heavily on biodiesel testing <http://www.youtube.com/watch?v=s32Ke2VzrqU>, not only at the production level but at the consumer level, where degraded fuel may cause engine failures.  Of major concern to diesel and biodiesel users is the very real possibility that water has contaminated their fuel. (See http://www.youtube.com/watch?v=0YcczdvPyAk).  The potential catastrophic impact of this problem is discussed at length  in this video at: http://www.youtube.com/watch?v=-lh4qhXc_5s&feature=youtube_gdata.
Fleet Fuel's  family of inexpensive biodiesel test kits  is just a click away on the internet at:
<http://fleetbiodiesel.com/biodiesel_testing_and_supplies.html>)