The video above shows Wilson Nelson, the face of Biowillie, saying truckers tell him they get better mileage with biodiesel. I have seen him say the same thing many times about Biowillie. I have heard the owner say the same thing as well. I just finished Willie's book, On the Clean Road Again where he mentions higher mileage several times. Ethanol's disadvantages are mentioned, but not energy content. Biodiesel has less energy content and this means lower mileage than regular diesel. Are those truckers wrong?
There are two types of diesel. B20, 20 percent biodiesel blend, is 2-3 percent less efficient than petrodiesel number 1. Diesel number 2 actually has a difference of 1-2 percent. There is a difference of 8 percent with B100 when compared with petrodiesel. Energy content is the only real determinator of fuel efficiency. So what might the truckers be seeing? Biodiesel's energy content can vary with feedstock. Diesel energy content can vary up to 15 percent depending on the provider and time of year. So it's very possible these truckers used petrodiesel that had much less energy content.
Biodiesel has a higher cetane rating. So there is a performance and lubrication improvement when using biodiesel. It's possible to improve mileage when you improve things like octance. It's well known that many older cars get better mileage with fuel additives. Performance improvement may also help more fuel efficient types of driving. So, there probably are truckers out there telling Willie they get better mileage and they are getting better mileage for sound technical reasons. I have never seen him say energy content is higher, just truckers tell him they get better mileage. So I don't think he has done anything legally wrong but I really think this needs further study. I doubt a large percent of truckers get higher mileage using biodiesel. Sorry, Willie.