Some tips to ease the pain at the gas pump
11-13-2007, 02:55 PM
#1
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Some tips to ease the pain at the gas pump
What you always wanted to know and were afraid to ask....how do we compensate for the rise in gasoline prices???? Now, we know....
I found this quite interesting, sorry if you don't.
Gas Pumping Tips from someone in the Petroleum pipeline business!!
I've been in petroleum pipeline business for about 31 years, currently working for the Kinder-Morgan Pipeline here in San Jose, CA. We deliver about 4 million gallons in a 24-hour period from the pipeline; one day it's diesel, the next day it's jet fuel and gasoline. We have 34 storage tanks here with a total capacity of 16,800,000 gallons. Here are some tricks to help you get your money's worth.
1. Fill up your car or truck in the morning when the temperature is still cool. Remember that all service stations have their storage tanks buried below ground; and the colder the ground, the denser the gasoline. When it gets warmer gasoline expands, so if you're filling up in the afternoon or in the evening, what should be a gallon is not exactly a gallon. In the petroleum business, the specific gravity and temperature of the fuel (gasoline, diesel, jet fuel, ethanol and other petroleum products) are significant. Every truckload that we load is temperature-compensated so that the indicated gallonage is actually the amount pumped. A one degree rise in temperature is a big deal for businesses, but service stations don't have temperature compensation at their pumps.
2. If a tanker truck is filling the station's tank at the time you want to buy gas, do not fill up; most likely dirt and sludge in the tank is being stirred up when gas is being delivered, and you might be transferring that dirt from the bottom of their tank into your car's tank.
3. Fill up when your gas tank is half-full (or half-empty), because the more gas you have in your tank the less air there is and gasoline evaporates rapidly, especially when it's warm. (Gasoline storage tanks have an internal floating 'roof' membrane to act as a barrier between the gas and the atmosphere, thereby minimizing evaporation.)
4. If you look at the trigger you'll see that it has three delivery settings: slow, medium and high. When you're filling up do not squeeze the trigger of the nozzle to the high setting. You should be pumping at the slow setting, thereby minimizing vapors created while you are pumping. Hoses at the pump are corrugated; the corrugations act as a return path for vapor recovery from gas that already has been metered. If you are pumping at the high setting, the agitated gasoline contains more vapor, which is being sucked back into the underground tank so you're getting less gas for your money.
Hope this will help ease your 'pain at the pump'.
I found this quite interesting, sorry if you don't.
Gas Pumping Tips from someone in the Petroleum pipeline business!!
I've been in petroleum pipeline business for about 31 years, currently working for the Kinder-Morgan Pipeline here in San Jose, CA. We deliver about 4 million gallons in a 24-hour period from the pipeline; one day it's diesel, the next day it's jet fuel and gasoline. We have 34 storage tanks here with a total capacity of 16,800,000 gallons. Here are some tricks to help you get your money's worth.
1. Fill up your car or truck in the morning when the temperature is still cool. Remember that all service stations have their storage tanks buried below ground; and the colder the ground, the denser the gasoline. When it gets warmer gasoline expands, so if you're filling up in the afternoon or in the evening, what should be a gallon is not exactly a gallon. In the petroleum business, the specific gravity and temperature of the fuel (gasoline, diesel, jet fuel, ethanol and other petroleum products) are significant. Every truckload that we load is temperature-compensated so that the indicated gallonage is actually the amount pumped. A one degree rise in temperature is a big deal for businesses, but service stations don't have temperature compensation at their pumps.
2. If a tanker truck is filling the station's tank at the time you want to buy gas, do not fill up; most likely dirt and sludge in the tank is being stirred up when gas is being delivered, and you might be transferring that dirt from the bottom of their tank into your car's tank.
3. Fill up when your gas tank is half-full (or half-empty), because the more gas you have in your tank the less air there is and gasoline evaporates rapidly, especially when it's warm. (Gasoline storage tanks have an internal floating 'roof' membrane to act as a barrier between the gas and the atmosphere, thereby minimizing evaporation.)
4. If you look at the trigger you'll see that it has three delivery settings: slow, medium and high. When you're filling up do not squeeze the trigger of the nozzle to the high setting. You should be pumping at the slow setting, thereby minimizing vapors created while you are pumping. Hoses at the pump are corrugated; the corrugations act as a return path for vapor recovery from gas that already has been metered. If you are pumping at the high setting, the agitated gasoline contains more vapor, which is being sucked back into the underground tank so you're getting less gas for your money.
Hope this will help ease your 'pain at the pump'.
11-13-2007, 04:25 PM
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hmmm...that one about filling up when the tank is half full makes alot of sense to me.
for some reason i seem to go like 200 and some change miles on the first half tank of gas, but then the second half seems to just evaporate and i only get another 100 or so.
i know the gas tank isn't shapped 100% even top to bottem, but that would explain it a bit.
for some reason i seem to go like 200 and some change miles on the first half tank of gas, but then the second half seems to just evaporate and i only get another 100 or so.
i know the gas tank isn't shapped 100% even top to bottem, but that would explain it a bit.
11-13-2007, 05:37 PM
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Regarding #1, fuel tanks, generally underground, stay at a constant temperature, and as a result, temperature above ground does not influence the temperature underground much. According to the email, expansion means you are getting less fuel at higher temperatures than cooler. OK, but that expansion and cooling occurs AFTER the fuel is pumped from underground. You still have the amount of fuel you pumped, but it will expand as the day gets warmer again.
Very long NIST fuel station testing PDF:
http://ts.nist.gov/WeightsAndMeasure...Course_302.pdf
Very long NIST fuel station testing PDF:
http://ts.nist.gov/WeightsAndMeasure...Course_302.pdf
11-13-2007, 06:50 PM
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Originally Posted by HeathenBrewing
Regarding #1, fuel tanks, generally underground, stay at a constant temperature, and as a result, temperature above ground does not influence the temperature underground much. According to the email, expansion means you are getting less fuel at higher temperatures than cooler. OK, but that expansion and cooling occurs AFTER the fuel is pumped from underground. You still have the amount of fuel you pumped, but it will expand as the day gets warmer again.
Very long NIST fuel station testing PDF:
http://ts.nist.gov/WeightsAndMeasure...Course_302.pdf
Very long NIST fuel station testing PDF:
http://ts.nist.gov/WeightsAndMeasure...Course_302.pdf
It was another toasty day on June 19, when representatives for the California Division of Measurement Standards showed up at a gas station in Riverside to check the temperature of the gasoline in the tanks.
What they discovered lent evidence to the allegation that consumers are being shortchanged by gasoline retailers and the oil industry.
The temperature in the underground tanks at the station was 94.4 degrees at 1 p.m. that afternoon, hotter than the roughly 90-degree air temperature, according to the agency's official log.
The measurements were part of a statewide survey that is coming amid allegations that an annual $2-billion rip-off is occurring nationwide because of hot gas.
As students of high school chemistry know, some liquids, particularly gasoline, expand when they get hot. But a gallon of expanded hot gas contains less energy, even though gas stations charge the same amount.
The energy content of a gallon of gasoline is based on fuel at 60 degrees. At the wholesale level, all transactions of gasoline are adjusted for the volume of gasoline or diesel when the fuel is at 60 degrees.
Each 15 degrees above the 60-degree standard increases the volume of the fuel by 1%. So each gallon of that 94.4-degree gasoline in Riverside contained 2% less energy.
You might say that amounts to a few cents per gallon. But the cents add up. The Owner-Operator Independent Drivers Assn., an organization representing truck drivers, estimates that the oil industry pockets about $2.3 billion annually from such overcharges. Long-haul truckers, who drive more than 100,000 miles per year, can get dinged by more than $700 annually, the group says.
"Southern California is the epicenter for this problem," John Siebert said. It has high temperatures, lots of cars and obviously a layout that requires absurd amounts of driving.
The association's estimates and other similar estimates are based on gasoline temperature data compiled by the National Institute of Standards and Technology, using environmental monitors on underground tanks at 1,000 stations across the nation. The data showed that gasoline in many middle-tier and Southern states is consistently above 60 degrees. In some cases, temperatures have popped over 100 degrees, said Siebert.
What they discovered lent evidence to the allegation that consumers are being shortchanged by gasoline retailers and the oil industry.
The temperature in the underground tanks at the station was 94.4 degrees at 1 p.m. that afternoon, hotter than the roughly 90-degree air temperature, according to the agency's official log.
The measurements were part of a statewide survey that is coming amid allegations that an annual $2-billion rip-off is occurring nationwide because of hot gas.
As students of high school chemistry know, some liquids, particularly gasoline, expand when they get hot. But a gallon of expanded hot gas contains less energy, even though gas stations charge the same amount.
The energy content of a gallon of gasoline is based on fuel at 60 degrees. At the wholesale level, all transactions of gasoline are adjusted for the volume of gasoline or diesel when the fuel is at 60 degrees.
Each 15 degrees above the 60-degree standard increases the volume of the fuel by 1%. So each gallon of that 94.4-degree gasoline in Riverside contained 2% less energy.
You might say that amounts to a few cents per gallon. But the cents add up. The Owner-Operator Independent Drivers Assn., an organization representing truck drivers, estimates that the oil industry pockets about $2.3 billion annually from such overcharges. Long-haul truckers, who drive more than 100,000 miles per year, can get dinged by more than $700 annually, the group says.
"Southern California is the epicenter for this problem," John Siebert said. It has high temperatures, lots of cars and obviously a layout that requires absurd amounts of driving.
The association's estimates and other similar estimates are based on gasoline temperature data compiled by the National Institute of Standards and Technology, using environmental monitors on underground tanks at 1,000 stations across the nation. The data showed that gasoline in many middle-tier and Southern states is consistently above 60 degrees. In some cases, temperatures have popped over 100 degrees, said Siebert.
And if you think the Oil companies aren't making money on this, then look at this:
the industry's arguments fall apart when you look at what happened in Canada in recent years. In general, Canadian gasoline is below 60 degrees, meaning consumers there were getting a break. The oil industry sponsored legislation that required temperature compensating equipment to protect itself from dispensing free gasoline.
11-13-2007, 07:08 PM
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Originally Posted by TheScionicMan
I disagree. Ground temps can change a lot over the course of a day, depending on your climate and proximity to large bodies of water, etc.
8000-gallon tanks do not dramatically change temperature in daily cycles. The insulated, fiberglass tanks tend to keep fuel at the temperature it was delivered… for a long time. Ask a station attendent for the automatic gauging meter report. It will tell you the temperature of the fuel in the underground tanks.
Besides, gas pumps deliver fuel by mass ... even with a density changed, flow is regulated not by volume, but mass (i.e. quantity of molecules).
This is one of the many many stories that "sounds good" on the surface, but when you analyze it, its full of holes.
11-13-2007, 07:17 PM
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The association's estimates and other similar estimates are based on gasoline temperature data compiled by the National Institute of Standards and Technology, using environmental monitors on underground tanks at 1,000 stations across the nation. The data showed that gasoline in many middle-tier and Southern states is consistently above 60 degrees. In some cases, temperatures have popped over 100 degrees, said Siebert.
And if its false, why are they doing it in Canada where the benefit is not in the Oil Companies favor? That speaks volumes.
11-13-2007, 07:34 PM
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Originally Posted by TheScionicMan
Ground temp may stay more constant if its solid ground. What if its a tank underneath a few inches of concrete with the sun shining on it for 8-10 hours?.
The thermal coefficient of thermal expansion (β) of gasoline is 9.5 x 10–4. Plug it into this equation
ΔV = βVΔT (C°)
To make a long story short, for a 20 gallon tank in a car, the difference is 0.008 gallons for each degree C. And this, remember, is for each degree the UST changes, NOT when the ambient air temp changes. Most tanks are 8000 gallons as well and hold temperature extremely well.
Originally Posted by TheScionicMan
And if its false, why are they doing it in Canada where the benefit is not in the Oil Companies favor? That speaks volumes.
If you are really interested in saving $$$ at the pump, learn how to drive CORRECTLY (not aimed at you personally, just a general statement).
11-13-2007, 07:49 PM
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What can I do at the gas pump to ensure that I am getting what I pay for?
Many factors draw motorists to a gas station, and price is near the top of the list. To be sure that you are being charged the correct amount based on the posted price, do the following:
--Keep in mind that your vehicle tank capacity in the owner's manual is only an estimate. It may hold more or less than the stated capacity.
--Check the prices posted on station signs that list the grade of gasoline and type of service you select (full, self, cash/credit). Make sure it is the same as the price per gallon on the dispenser face for the grade and type of fuel. Carefully note any qualifications or conditions required to obtain the discount for the cash/credit price.
--Make sure that the numbers on the face of the dispenser for SALE and GALLONS are set to ZERO before you begin pumping gas. If the previous sale still appears on the dispenser when you start pumping gas, you can become the victim of an "inflated" purchase.
--Multiply the indicated gallons delivered by the price per gallon to assure that the dispenser is correctly computing the price. (If you do not have time to do this at the station, get a receipt or write the numbers down and do the math at home.)
--If you make a credit card purchase, check to be sure you have been charged the correct amount and take your receipt with you.
--At full-service stations, observe attendants as they fill your tank or add liquids such as oil, transmission fluid, engine coolant to be sure they add the entire product. Ask the price of these products before the attendant opens the containers.
My advice, find a station that's 1 or 2 cents less, call it even, and find something useful to do with your time, like work on peace in the Middle East or global warming.
11-13-2007, 08:01 PM
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Originally Posted by TheScionicMan
And if you think the Oil companies aren't making money on this, then look at this:
the industry's arguments fall apart when you look at what happened in Canada in recent years. In general, Canadian gasoline is below 60 degrees, meaning consumers there were getting a break. The oil industry sponsored legislation that required temperature compensating equipment to protect itself from dispensing free gasoline.
According to Brendan Hawley, “there’s no penalty or there’s no unfair unadvantage gained by the use of ATC.” Hawley is with the Canadian Petroleum Products Institute in Ottawa, an organization that represents the refining and marketing sectors. He doesn’t like to talk about the effect temperature compensation has on volume; the more important issue, he says, is energy.
“If it’s warmer than 15 degrees, you’re getting more product than what you pay for,” Hawley says. “When you’re at 15, below 15 degrees … it takes less volume to achieve that same energy content. “You’re getting the same energy content in slightly different volumes. Lower in winter, higher in summer.”
Hawley says it doesn’t matter that you’re getting less volume, because you’re still getting the same amount of energy and your car will still travel the same distance.
i thought it was just me haha
11-13-2007, 09:34 PM
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I think people should be informed on a topic of such importance. Last thing we need is another wacky gimmick fuel saver, like miracle magnets and vortex generators.
Then again, ignorance is bliss......
Then again, ignorance is bliss......
11-13-2007, 10:28 PM
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Originally Posted by HeathenBrewing
."...the NIST found that the average annual temperature of fuel stored in those underground tanks was 64.7 degrees...."
No where near the 100 degreees mentioned i nthe article.
No where near the 100 degreees mentioned i nthe article.
11-13-2007, 10:35 PM
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Originally Posted by TheScionicMan
Originally Posted by HeathenBrewing
."...the NIST found that the average annual temperature of fuel stored in those underground tanks was 64.7 degrees...."
No where near the 100 degreees mentioned i nthe article.
No where near the 100 degreees mentioned i nthe article.
But that does nothing to address thermal expansion of liquids though.