Dzlsabe also wondering. Instead of commercials and trade-shows and Big oil/ag "free-marketeers", maybe gettin that ULSD/B2-20 mix in at least some interstate truckstops would be a start...eh?

Petro-diesel requires about 25% more oil per gallon produced than gasoline. As such...a gallon of B20 will consume about the same amount of oil as a gallone of gasoline. This the primary reason that oil companies and automotives push B5 and B20 blends and never B100.

They don't want to change the game. They just want to make folks feel good, while still retaining our full dependence on oil.

If you are a bio-diesel proponent like me...then push for B100 all the way.

Actually diesel requires less oil per gallon produced than gasoline....and gives significantly better mileage per gallon than gasoline.

Aj

It really annoys me that they concentrate on these low blends - the manufacturers are being far too conservative.

To me, even B20 is a low blend - I use B100 most of the time in my VW car.

B100 and Aj. Please provide documentation. All I hear are assertions by both sides of the diesel debate.

Ok, maybe it is true that Diesel might require more oil per gallon then gasoline, but those part of oil made of diesel we cant break it into gasoline, or require huge energy to really break them into gasoline. Therefore, diesel is diesel, gasoline is gasoline. You cant yeild 100% gasoline or 100% diesel from a gallon of oil, you just get some of both.

Maybe until someday some agricultural giants will take over the energy business from the oil giants. B100 or D100(diesel 100%) really doesnt matter, we consumer only tends to use whatever cheapest available.

The ideal senarior should be each of us play a role in planting this fuel and perhaps make our own fuel. Before this we need to discover a fuel that can have reasonable yeild in small scale with cheap cost. By then every small town will have their own fuel maker. No more big crab shell or mobile tanker dominating the market.

Odograph's source (source link) claims well-to-tank efficiency of 87.9% for diesel, 82.9% for gasoline.

To put it bluntly, B100 is full of hooey.

Maybe due to the fact that diesel require less refinary work then gasoline. Diesel is easier to extract from crudes.

B100, seriously, do you really believe that this is sustainable at the moment?

Those numbers seem pretty close to mine, available here: http://www.mda.state.mn.us/ethanol/balance.html
Aside from the difference in numbers, it's pretty well known that diesel takes less energy to produce than gasoline. The added refining necessary for the new ULSD might narrow the gap, but i expect diesel to continue to be more efficient.
Aj

This guy stating that "diesel requires about 25% more oil per gallon produced than gasoline" posts this same rubbish on nearly every article. He's a broken record. It's not worth trying to prove any points with him, because he just doesn't understand the concept of well-to-wheel efficiency.

He also fails to grasp the fact that high concentrations of biodiesel are not possible RIGHT NOW because of limited supply. So, should we not do anything until we can produce the required biodiesel for 100% blends in every diesel engine?

Gaining the public's acceptance of B5 will lead to higher concentrations over time. You have to start somewhere.

Angelo,

I don't think anybody tries to prove anything to that guy.
Some more knowlagable people know as a fact that diesel takes less energy to produce than gasoline.
But there is number of people that do not know this fact and when they read statments like this multiple times they might actually believe it.
I personally don't believe any of those statments unless I see real data from reliable source.
As old saying goes 'repeat lie until it becomes a truth'.
Thank you Engineer-Poet and Aj for providing source.

Every time I see these posts though, I feel obligated to dispute it for that very reason - people may start to believe it! I understand he's trying to make a point for more biodiesel, so he's probably not bad intentioned.

However, even if we were to discount the fact that diesel requires less energy to refine than gasoline and all of the other variables accounted for in a well-to-wheels measurement, I still find it hard to accept that he continues to ignore the 30% higher energy density of diesel!

Interesting article. There is an error in your table comparing old and new VWs, however. I believe the acceleration times are for 0-100 km/h not mph, since the 1975 model could only attain 87 mph as stated in the same table (also personally verified as a past owner of a 1978 Rabbit diesel with the same engine).

That 30% higher energy density come at a price: higher carbon intensity. 40 MPG Gasoline emits less carbon than a 40 MPG Diesel, but this is largely made up by the (generally) better efficiency of diesels when comparing equivalent engines, but it's something to keep in mind when comparing the numbers.

Schwa. How much less carbon does gasoline emit?

According to EPA:

“…With all other things being equal, today’s diesel engines are projected to achieve up to 40% higher fuel economy than today’s gasoline engines, which is equivalent to about a 29% savings in fuel consumption. Since diesel fuel contains about 15% more energy and carbon than an equal volume of gasoline, a vehicle mile traveled with a diesel engine that has 40% higher fuel economy should reduce vehicle energy consumption and carbon emissions by about 18%. On a life-cycle basis, the total benefit of diesel engines is somewhat higher because there are higher per gallon energy losses for gasoline production than for diesel fuel production…”

http://www.epa.gov/otaq/technology/420r05012.pdf

Finally, some GOOD, HARD FACTS on the issue!

According to TerraPass, a gas engine emits 19.5 lbs CO2 per gallon consumed (http://www.terrapass.com/calcdetails.html#cantfindcar).

Plugging various diesel models into their calculator (http://www.terrapass.com/carboncalc.php) & doing the math yields 22.9 lbs CO2 per gallon, but the "per mile" number is obviously lower due to the better fuel mileage of diesels. Assuming 40% as in Carl's quote from the EPA, I calculated a 16% improvement in emissions.

According to the U.S. Dept. of Energy, using B100 will reduce CO2 emissions by 75% vs. petroleum diesel, or down to less than 6 lbs per gallon (http://www.eere.energy.gov/afdc/altfuel/bio_benefits.html).

Yo B100....What oil/auto companies are pushing B5/B20? With the exception of VW and DC all I see is Bzero. Surely you would concur that a foot or toe in the door is preferable to neither. B100 is not without its problems...namely cold-weather and engine timing/emissions issues.

Yo B100 guy, stop posting that BS about gas being more efficient to produce than Diesel, It is not! and you just make greencarcongress.com look bad, as well as annoying a load of people who feel obliged to put out the facts.
Do you work for the US government or something?

Stop it! ok!

Thanks.