What's The Story On Winter And Summer Blends Of Gas?.......

[global1]

I just heard a report on radio news here in Chicago that we can expect gas prices to go up to $4.60 per gallon in the summer. The reasons they gave were: 1. tensions in the Middle East; 2. increased demand in summer and 3. the changeover from the winter to summer blend.

Why do we change blends? What is the purpose of that? Is there a valid reason for it or is is just there to provide the oil companies with a good excuse to raise prices?

[Atman]

1. Well, once upon a time...

Seriously, this story if full of shit, and totally backward. Gas is funny stuff, and I'm sure some DU scientist will eventually post the formulas, but the reality is that gasoline burns differently at different temperatures. So, in the winter, the gas has a different formulation than the gas you put in your car in the summer. And the winter stuff gets shittier mileage. And it is MORE EXPENSIVE. That is where the fairy tale comes in. The summer gas should cost LESS, not more, because of the formulation. The fact that the refineries have to change over means nothing, they've had to do that for years.

It sounds like a total BULLSHIT EXCUSE to me.

.

[Mopar151]

8. The cost issue has to do with the relative cost of various gasoline components.

The "high aromatics" are in great demand, because of their higher natural octane, clean burning, and the market for other uses (think lacquer thinner here). And the lesser components can be made more easily from the more common "sour crude".
F'r instance, Sunoco now makes only racing gasoline in their old Marcus Hook, NJ refinery - because that refinery is set up for nice, expensive, Lybian or Saudi sweet crude.

[NoGOPZone]

10. However, Sunoco will be selling Marcus Hook as they exit the refining business

They will still retail gasoline.

http://www.thestreet.com/story/11238966/1/sunoco-to-exit-the-refining-business.html

[Mopar151]

17. They may well spin off the race gas business.

Union 76 did - they are now Rockett Brand, run by the same guy who ran the business under Union 76. Also, the New England distributor for Sunoco Race Fuels has been bragging about the dedicated refining and transport for race fuel - A sellout to a consortium of distributors could be in the offing.

[TheWraith]

2. Yes, actually it's required by the EPA.

"Summer" gas is a slightly lighter form of gas than winter gas, and evaporates more easily, making it more eco-friendly and likely to produce less persistent pollution. However, it's not as efficient in cold-weather months--the different consistency makes it harder to start cars, and smog isn't the same kind of problem in the winter.

[global1]

12. Is It Possible To Formulate A Compromise Blend That Could Be Used Year Round......

something that has the characteristics of both of the current summer and winter blends? Don't we have oil or gasoline chemists that could come up with something like this or don't the oil companies want to come up with a compromise. Seems to me with all this talk about alternate forms of energy that the oil companies would want to throw us a bone once and awhile to make us think that they are not so bad.

[TheWraith]

13. Truthfully, I don't know.

Chemistry is probably my weakest subject scientifically, so I don't really know that much about the practical aspects of hydrocarbon mixing. I do know that it's generally speaking more complicated than it sounds--when producing gas "cocktails" it's necessary to balance volatility, engine performance, evaporation inside the tank, behavior in the fuel system, etcetera, in such a way that it not only minimizes pollution but also works for every single vehicle ranging from the most modern to old 1960s models still on the road.

That said, the difference in blends is mandated by federal law, not something that oil companies choose to do or would be willing to do without being required.

[Mopar151]

22. Maybe. In a moderate climate, in some cars.

And it'll work about as well as "all season" tires do - that is, pretty crappy compared to high-performance snow or summer tires, especially at the extremes of climate and performance.
This isn't a new problem, but it's one of a battery of excuses that are trotted out when the speculators are skimming value off the top, and refineries are being closed to keep supplies short.

[Mopar151]

3. We change blends because the temperature changes.

Has to do with some physical carachteristics of the various gasoline blends - the major one being volatility. Winter blend gas vaporizes more easily, to aid in cold starting and operation - while summer blend is less prone to "vapor lock" - literally boiling in the fuel line, blocking the flow of liquid gasoline.
This carachteristic also has a lot to do with unburned hydrocarbon (HC) emissions. In pre-emission control LA, about half the HC emissions were vapors released from vehicle and storage fuel tanks.

[appleannie1]

4. On a certain date all stations have to change over from the winter blend to the summer blend.

It has to do with pollution and how it burns. For the last couple years they have used that to say there are shortages and have raised prices. It is total bull because the rules have been the same, the date of change over has been the same for many years so it is not some great surprise. They could easily start making the blend that they will need in advance to eliminate any shortages.

[izquierdista]

5. Good reason to run on diesel

Tinkering with the vapor pressure for summer and winter conditions is a non-problem.

[JustABozoOnThisBus]

9. I thought diesel was even more temp-sensitive

... that the summer "blend" will gel or turn waxy in cold weather, making starting difficult.

Is that false?

http://en.wikipedia.org/wiki/Winter_diesel_fuel

[TheWraith]

14. You're correct, pure diesel turns to a gel at 17.5 degrees.

Additives typically bring the gel point down to -10 degrees, and some can go as low as -20, however there are still "summer" and "winter" blends of diesel, since some of those winter additives can cause the fuel to gel at warmer temperatures.

[Bandit]

6. Because of Temperture

Normally furnaces use number 2 diesel instead of heating oil #1 diesel. Number 2 diesel is less refined and has a tendency to sludge up at low temps. So if your tank is not buried and above ground a blend of the two is used to prevent problems...It usually is not a problem in trucks unless the truck is left to sit for a spell...Number one diesel or heating fuel as it is commonly called does not need to be blended if that is what you normally use..

[banned from Kos]

7. all three of your reasons (1,2,3) are true every year. I notice many fear-mongering stories

like this now.

Right-wingers use fuel prices as a tactic although the peak was 2008 under Bushy-Boy.

[TexasProgresive]

11. Here's some good information from the OilDrum

According to this piece the gasoline has to be formulated to raise the boiling point in summer where it gets very hot -like Texas. This limits the about of gasoline vapors escaping into the atmosphere which is a source of air pollution.

http://www.theoildrum.com/story/2006/9/13/234043/431

[qb]

15. I believe the science, but I also believe in price manipulation.

Something "happens" to trigger a price increase, and the price increases instantaneously.
If the situation reverses, the prices drift down ever so gradually.
Meanwhile, the oil companies rake in billions.

[Proud Liberal Dem]

19. I've long believed (and I stand by this)

that all the major oil execs meet in the bowels of a smoke-filled room somewhere every morning and come to a mutual agreement on a daily "excuse" for having to hike gas prices that they immediately hammer out and deliver to all major media outlets.

either that or they just randomly spin a "wheel of excuses" to get their talking points for the day. I still haven't worked out how price drops factor into it though they're probably smart enough to realize that they can't keep prices sky-high forever. Either that or they're just doing it to mess with our minds.

[banned from Kos]

20. No chance. OPEC? Yes. Exxon and PVSDA or Statoil or Petrobras? No way.

"all the major execs" = thousands with different interests.

[Proud Liberal Dem]

21. I'm really only being half-serious

I know logistically what I wrote sounds ludicrous but so are the oil companies IMHO.

[hunter]

16. Modern fuel injected cars don't care so much.

Back in the olden days when most cars had carburetors, a car that got summer gas in the winter would refuse to start. The gasoline would just sit in the engine as a puddle.

If an old car got winter gas in the summer it wouldn't stop. When you turned the ignition off the car would "diesel" and continue to run as gas continued to vaporize in the carburetor. Or when it was running it would get "vapor lock" when the fuel would start boiling in the fuel lines and block further flow of liquid gasoline from the tank, or boil in the carburetor and flood the engine with too much gas.

Gas that vaporized too easily in the summer was also an environmental problem since the fuel systems of old cars weren't sealed. Any gasoline that vaporized was simply vented into the air.

Modern engines have sealed fuel systems, and the fuel injectors work at high pressure. The fuel injectors disperse liquid gasoline as a much finer mist than a carburetor does, which improves winter starting, and the much higher fuel system pressures reduce problems with premature vaporization of the gasoline.

But newer cars will eventually vent gasoline vapors if the pressure gets too high, and they won't run quite as cleanly when they first start on out-of-season gas, which is now the primary reason for the switch, other than supporting older vehicles like my truck.

Still, changing the blend is a silly reason to raise prices. It's not like the oil companies are caught by surprise every time the seasons change...

Or maybe the pointy haired bosses of giant corporations really are bozos incapable of looking beyond the next financial quarter; maybe the change of seasons does catch them by surprise every year... "Holy shit! It's going to be summer again! Oh no! We'll have to reformulate our gasolines! And there are tensions in the Middle East and demand is up!! Dear God! How could this happen to me?"

[Mopar151]

18. Dilbert's pointy-haired boss is alive and dumb as ever

Throughout American business.