Filed under: Biodiesel, Hybrid, Toyota, Volkswagen
Biodiesel Jetta uses far fewer fossil fuels than a Prius, says university biodiesel group
I'm not certain when this information was released to the web, but I just discovered it today, via Propel Biofuels. The University of New Hampshire biodiesel group compared the energy use of six vehicles - a Jetta TDI using biodiesel, a Jetta TDI running on petroleum diesel, a Jetta 2.0L with a gasoline engine, a Toyota Prius burning gasoline, a Toyota Fuel Cell vehicle (hydrogen), and a Dodge ESX3 (diesel-hybrid) on biodiesel. But what's really missing from the chart is an explanation of what blend (if any) the biodiesel is.
Anyway, UNH found that the Prius costs less per mile to operate, but the biodiesel Jetta wins - by a lot - the fossil energy input/mile (OK, the Dodge ESX3 concept beats the biodiesel Jetta, but where you gonna find one?). A footnote explains that energy input per mile was "calculated based on 50/50 average fuel mileage and energy balance of creating fuel, using 3.2:1 for biodiesel (when made from soy), 0.83:1 for petroleum diesel, 0.74:1 for gasoline, and 0.5:1 for hydrogen (based on electrolysis of water)" so that it "equals (energy density of fuel )/[(fuel efficiency (mpg))*Energy balance]."
So, all you biodiesel fans and hybrid lovers, what does this chart say to you?
[Source: University of New Hampshire]
Reader Comments (Page 1 of 1)
Jimmy 11:22PM (5/09/2007)
No great surprise here, biodiesel is a fantastic fuel! Based on the UNH numbers a Jetta TDI on biodiesel easily beats the mythical 100mpg Prius hybrid.
Meanwhile, seven years ago the VW 3L Lupo TDI drove around the world, 33,333 km through Africa, Asia, Australia, North and Central America and Europe, using 792.57 litres in an unmodified production car, on real roads in real traffic and driving at realistic speeds. That is 98.9mpg US!
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Mulad 12:43AM (5/10/2007)
Yeah, running the numbers they have, they're talking 100% biodiesel. But yeah, the page is probably pretty old. The Dodge ESX3 concept appeared in 2000. The mileage numbers for the Prius appear to be from the previous generation (up to 2003) vehicle, and the Jetta numbers appear to be from the 4th gen (up into 2005) car. Since that time, the Prius got better and the Jetta got worse. Still, if you are willing/able to run on B100, a Jetta will have a "long gas pump" which used less petroleum, even if you compared it to a hypothetical Prius that ran on 100% ethanol. Even then, the Jetta might be better by half.
Too bad biodiesel still isn't that common, though at least it's getting better every day. Also, too bad that Volkswagen doesn't want anyone using it in higher than 5% concentration, but I digress...
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jcwinnie 9:29AM (5/10/2007)
"OK, the Dodge ESX3 concept beats the biodiesel Jetta, but where you gonna find one?"
Seb, are you not supposed to add neener-neener to that?
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Jimmy 2:45PM (5/10/2007)
I ran some more numbers...
2006 TDI Jetta using EPA city/highway numbers and running on B20 biodiesel blend (from Soy biodiesel as in the UNH numbers) is 2.75 KBTUs of fossil energy per mile.
A 2007 Prius using the EPA city/highway numbers uses 2.99 KBTUs of fossil energy per mile.
So even using just 20% Soy Biodiesel the TDI uses less total fossil fuel. Even if you switch to 2008 EPA numbers, a TDI on B20 still wins.
B20 is not that hard to find either. I think apart from NJ and WV, every state has at least one biodiesel retailer.
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David 4:47PM (5/10/2007)
Have said for a long time biodiesel is the way to go. How many cars and trucks can you buy with diesel engins in the USA? About as many as flexfuel. In either case Detriot does not want to change. Put a flexfule or diesel engin in every car and truck and wahch the petrileum consumption drop.
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RootHub 2:53PM (6/05/2007)
I have a 2006 Jetta tdi that I run on B20 in Los Angeles.
This is my first new car.
I love driving this autmobile.
People are pretty amazed when I tell them that it runs biodiesel without modification, and about the mileage that it gets.
Then when they hear that I'm paying $2.98 compared to the avg $3.50 here in LA.
That's what really gets them interested.
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Roy 4:09PM (6/12/2007)
biodiesel is the best alternative fuel it give the user independence from large companies as the user can make it at his own will if he pleases or buy it of shell (in some places) or off the pump so BIODIESEL is also about INDEPENDENCE
http://boilkerala.blogspot.com
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Rvalencia 10:58PM (6/27/2007)
Use E10 on Prius.
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mark 6:54PM (2/24/2009)
Energy for vehicles is actually a 2 pronged problem. One issue is storage of energy in a transportable form. Biodiesel beats the Prius on this. But the other issue is the energy creation itself. Fossil fuels were created eons ago so they don't need to be created, just refined into a good storage medium like gasoline. Biodiesel is not the answer as an energy source unless we can figure out a way to make the necessary volumes of fuel without using much land for plants, and without using much fertilizer. Otherwise it's a dead end. Billions of gallons of biodiesel would be needed, in direct competition with out stomachs for food.
The Prius on the other hand as a transitional energy user uses batteries to store energy. Right now that energy is from gasoline. With the plug in Prius, that energy can be from any source. The key is storage and only secondarily the creation of energy.
What the Prius has done is expand research in the storage of energy in forms that do not require fossil fuel refining, nor fossil fuel creation.
And another thing. America's safety depends not on not needing Arab oil any more, but on making Arab oil worthless. Biodiesel will never make petroleum worthless, further progress in electricity creation and storage will.
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