MPG's (difference with bio D vs. SVO vs. regular diesel?) - Fuel Economy, Hypermiling, EcoModding News and Forum

ucftabletennis · 09-10-2009, 04:23 PM

Will your vehicle obtain better MPG's by using Biodiesel or even straight vegetable oil, rather than running on regular diesel??

craig138 · 03-29-2012, 10:21 PM

drmiller100 · 03-29-2012, 10:42 PM

diesel is a funny thing. when they went to super low sulphur, we all suffered loss of MPG.

look at this chart, then consider diesel now has less btu's then when it was written.

Biodiesel Fuel

redpoint5 · 03-29-2012, 10:54 PM

Good link. So according to that info, 7-10% drop in mpg due to bio-fuels. What percent BTU drop is ULSD compared to LSD?

Ryland · 03-30-2012, 09:19 AM

People I've talked to said that they didn't notice any drop in mileage, due partly to the added top end lubrication of bio-diesel.
But even if it's a 10% drop in mileage (haven't heard anyone have that happen) it's still a 100% reduction of petroleum diesel and oil crops produce enough oil that farmers can grow their own fuel, press it on site and come out ahead, from what I remember energy input in to making bio-diesel was less then 10% of what you get out of it, corn ethanol is no where near that efficient.

drmiller100 · 03-30-2012, 10:57 AM

actually, biodiesel is MUCH more expensive then ethanol to produce. Biodiesel is from oil - takes a LOT of plant oil to make biodiesel.

ethanol is starch/sugar. lots of starch/sugar in plants. that is the reason ethanol is so much cheaper to buy then biodiesel.

euromodder · 03-30-2012, 11:32 AM

Quote:

Originally Posted by drmiller100

actually, biodiesel is MUCH more expensive then ethanol to produce. Biodiesel is from oil - takes a LOT of plant oil to make biodiesel.

If they stick to rapeseed , that is.
There are plants that yield far more oil than rapeseed or soy.

Ryland · 03-30-2012, 12:41 PM

Quote:

Originally Posted by drmiller100

actually, biodiesel is MUCH more expensive then ethanol to produce. Biodiesel is from oil - takes a LOT of plant oil to make biodiesel.

ethanol is starch/sugar. lots of starch/sugar in plants. that is the reason ethanol is so much cheaper to buy then biodiesel.

Ethanol also gets huge government subsidies, around 50-70 cents per gallon? the person who told me that bio-diesel was not very energy intensive to produce was a farmer who has been growing oil crops for bio-diesel for a number of years now and they wanted to find out for sure how much energy it took them to produce their fuel so they kept records of all the fuel used to produce the fuel they used on the rest of their farm along with electricity used to run the press and all of their other inputs, I wish I could find my notes, but it was a tiny amount of energy was going in to their fuel.

oil pan 4 · 03-30-2012, 01:54 PM

When I would process WVO for use I put almost no energy into it, just a little time.
Even then when Diesel was around $3/gal I could produce at least $30 worth of fuel per hour spent on it, bigger batchs yelded a higher $/hour number, over $40 per hour sometimes.

UFO · 03-30-2012, 03:42 PM

Quote:

Originally Posted by drmiller100

actually, biodiesel is MUCH more expensive then ethanol to produce. Biodiesel is from oil - takes a LOT of plant oil to make biodiesel.

ethanol is starch/sugar. lots of starch/sugar in plants. that is the reason ethanol is so much cheaper to buy then biodiesel.

I don't believe that. Making biodiesel is a very simple process with cheap materials. Ethanol requires large amounts of water and energy to make.

I get slightly better mileage with biodiesel; I attribute that to higher cetane as the energy level of B100 is very close to ULSD.