View Full Version : Fuel prices-BTU's per Gal.
jerry wass
May 30th 07, 04:10 PM
Don't like to beat a dead horse, but--
As C.S. Nixon said--"let me make myself perfectly clear"
I agree that a gallon of Mogas has more btu's than a gallon of Avgas
The main reason being--1 gal mogas= 7.422 lbs.
1 gal avgas= 6.978 lbs.
Q.E.D.
GeorgeB
May 30th 07, 08:58 PM
On Wed, 30 May 2007 15:10:29 GMT, Jerry Wass >
wrote:
>Don't like to beat a dead horse, but--
>
>As C.S. Nixon said--"let me make myself perfectly clear"
>
>I agree that a gallon of Mogas has more btu's than a gallon of Avgas
>
>
>The main reason being--1 gal mogas= 7.422 lbs.
> 1 gal avgas= 6.978 lbs.
>
>Q.E.D.
Per Wikipedia, and my friends who do weight/balance calcs, the avgasd
number above is alittle, like 18%, off ...
Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and
this density is commonly used for weight and balance computation.
Density increases to 6.40 lb/US gallon at -40 °C, and decreases by
about 0.5% per 5 °C increase in temperature.[3]
[3] is # ^ MacDonald, Sandy A. F.; Isabel L. Peppler [1941] (2004).
"Chapter 10. Airmanship", From The Ground Up, Millennium Edition,
Ottawa, Ontario, Canada: Aviation Publishers Co. Limited, pp. 265,
261. ISBN 0-9680390-5-7.
AirBP says "AVGAS 100LL: Aviation Gasoline for Reciprocating Engines
with lower maximum lead content. Color: Blue. Flash point: Below 0
degrees F. API gravity: 64-7. Relative density: .6582-.7238".
Water is likely the density of 1.000, and is about 8.34 lb/gal
suggesting the 6 lb/gal is a pretty good number.
I'd like to know the source for your 6.978 ...
Barnyard BOb
May 30th 07, 10:37 PM
Jerry Wass wrote:
>Don't like to beat a dead horse, but--
>
>As C.S. Nixon said--"let me make myself perfectly clear"
>
>I agree that a gallon of Mogas has more btu's than a gallon of Avgas
>
>
>The main reason being--1 gal mogas= 7.422 lbs.
> 1 gal avgas= 6.978 lbs.
>
>Q.E.D.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Jerry,
Your pet horse may be dead...
but, the autopsy is not yet complete.
Check out the posts after yours.
P.S.
You made yourself perfectly clear while absorbed
in computing one error after another. <G>
I simply choose to cut to the chase,
posting what the experts established,
probably, a half century ago.
HOW it's done, matters not to me.
I could have presented the math here,
if required, and had your ambition.
Kudos for your efforts and more importantly...
your willingness to admit mistakes. Takes a
real man to do that.
Be well.
- Barnyard BOb -
jerry wass
May 31st 07, 01:25 AM
GeorgeB wrote:
> On Wed, 30 May 2007 15:10:29 GMT, Jerry Wass >
> wrote:
>
>> Don't like to beat a dead horse, but--
>>
>> As C.S. Nixon said--"let me make myself perfectly clear"
>>
>> I agree that a gallon of Mogas has more btu's than a gallon of Avgas
>>
>>
>> The main reason being--1 gal mogas= 7.422 lbs.
>> 1 gal avgas= 6.978 lbs.
>>
>> Q.E.D.
>
> Per Wikipedia, and my friends who do weight/balance calcs, the avgasd
> number above is alittle, like 18%, off ...
>
> Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and
> this density is commonly used for weight and balance computation.
> Density increases to 6.40 lb/US gallon at -40 °C, and decreases by
> about 0.5% per 5 °C increase in temperature.[3]
>
> [3] is # ^ MacDonald, Sandy A. F.; Isabel L. Peppler [1941] (2004).
> "Chapter 10. Airmanship", From The Ground Up, Millennium Edition,
> Ottawa, Ontario, Canada: Aviation Publishers Co. Limited, pp. 265,
> 261. ISBN 0-9680390-5-7.
>
> AirBP says "AVGAS 100LL: Aviation Gasoline for Reciprocating Engines
> with lower maximum lead content. Color: Blue. Flash point: Below 0
> degrees F. API gravity: 64-7. Relative density: .6582-.7238".
>
> Water is likely the density of 1.000, and is about 8.34 lb/gal
> suggesting the 6 lb/gal is a pretty good number.
>
> I'd like to know the source for your 6.978 ...
My Sources are: a 5 gal can of Avgas bought for break-in purposes on my
rebuilt engine--about two weeks ago, and kept in a S.Steel can of the
variety used for holding Coke/Pepsi syrup at vending booths.--air tight.
good for 125 psi(has to hold the CO2 pressure)
a 5 gal jug of Mogas bought a week ago for my lawnmower.
a 250 CC graduated Lab-type beaker, & a metric balance type scale
accurate to 0.1 gm.
The Avgas weighed 168.3 gms/250cc---The Mogas weighed 179.0gm/250cc----
Please let me know If I made any mistakes in the conversion----If not,
I'll re-weigh two more samples tomorrow..
clare at snyder.on.ca
May 31st 07, 01:45 AM
On Thu, 31 May 2007 00:25:09 GMT, Jerry Wass >
wrote:
>GeorgeB wrote:
>> On Wed, 30 May 2007 15:10:29 GMT, Jerry Wass >
>> wrote:
>>
>>> Don't like to beat a dead horse, but--
>>>
>>> As C.S. Nixon said--"let me make myself perfectly clear"
>>>
>>> I agree that a gallon of Mogas has more btu's than a gallon of Avgas
>>>
>>>
>>> The main reason being--1 gal mogas= 7.422 lbs.
>>> 1 gal avgas= 6.978 lbs.
>>>
>>> Q.E.D.
>>
>> Per Wikipedia, and my friends who do weight/balance calcs, the avgasd
>> number above is alittle, like 18%, off ...
>>
>> Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and
>> this density is commonly used for weight and balance computation.
>> Density increases to 6.40 lb/US gallon at -40 °C, and decreases by
>> about 0.5% per 5 °C increase in temperature.[3]
>>
>> [3] is # ^ MacDonald, Sandy A. F.; Isabel L. Peppler [1941] (2004).
>> "Chapter 10. Airmanship", From The Ground Up, Millennium Edition,
>> Ottawa, Ontario, Canada: Aviation Publishers Co. Limited, pp. 265,
>> 261. ISBN 0-9680390-5-7.
>>
>> AirBP says "AVGAS 100LL: Aviation Gasoline for Reciprocating Engines
>> with lower maximum lead content. Color: Blue. Flash point: Below 0
>> degrees F. API gravity: 64-7. Relative density: .6582-.7238".
>>
>> Water is likely the density of 1.000, and is about 8.34 lb/gal
>> suggesting the 6 lb/gal is a pretty good number.
>>
>> I'd like to know the source for your 6.978 ...
>
>My Sources are: a 5 gal can of Avgas bought for break-in purposes on my
>rebuilt engine--about two weeks ago, and kept in a S.Steel can of the
>variety used for holding Coke/Pepsi syrup at vending booths.--air tight.
>good for 125 psi(has to hold the CO2 pressure)
>
>a 5 gal jug of Mogas bought a week ago for my lawnmower.
>
>a 250 CC graduated Lab-type beaker, & a metric balance type scale
>accurate to 0.1 gm.
>
>The Avgas weighed 168.3 gms/250cc---The Mogas weighed 179.0gm/250cc----
>
>Please let me know If I made any mistakes in the conversion----If not,
>I'll re-weigh two more samples tomorrow..
Sounds right to me. SG has an effect on the energy content, but it is
NOT an indicator of octane. MoGas has a higher energy density than
AvGas (generally).
--
Posted via a free Usenet account from http://www.teranews.com
Barnyard BOb
May 31st 07, 06:23 AM
Jerry Wass wrote:
>I agree that a gallon of Mogas has more btu's than a gallon of Avgas
>
>
>The main reason being--1 gal mogas= 7.422 lbs.
> 1 gal avgas= 6.978 lbs.
>
>Q.E.D.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Not true, Jerry.
Ready Reference Files
Weight of One Gallon (U.S.) of Water, Gasoline, and Ethanol
1 gallon of water equals 8.33 lbs.
1 gallon of gasoline equals 5.8 to 6.5 lbs.
1 gallon of ethanol equals 6.59 lbs.
Source: U.S. Dept. of Energy. Fuel From Farms: a Guide to Small Scale
Ethanol Production. May 1980. Page D-3.
Verified by: JT, 9/98
Disclaimer:
While the Library has verified the information presented in these
files in what it considers to be reliable and authoritative sources,
it cannot take responsibility for nor guarantee the accuracy of the
information presented.
---------------------------------------
Avgas
From Wikipedia, the free encyclopedia
Properties
Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and
this density is commonly used for weight and balance computation.
Density increases to 6.40 lb/US gallon at -40 °C, and decreases by
about 0.5% per 5 °C increase in temperature.[3]
GeorgeB
May 31st 07, 02:16 PM
On Thu, 31 May 2007 00:25:09 GMT, Jerry Wass >
wrote:
>>> The main reason being--1 gal mogas= 7.422 lbs.
>>> 1 gal avgas= 6.978 lbs.
>> Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and
>The Avgas weighed 168.3 gms/250cc---The Mogas weighed 179.0gm/250cc----
>
>Please let me know If I made any mistakes in the conversion----If not,
>I'll re-weigh two more samples tomorrow..
Plugging your avgas numbers into my conversion software, I get 0.371
lb / 0.066 gal for your measurements ... which my calculator gives as
5.62 lb.gal. I didn't run the mogas.
One of us has bad conversion data, maybe both of us.
George
jerry wass
May 31st 07, 02:49 PM
GeorgeB wrote:
> On Thu, 31 May 2007 00:25:09 GMT, Jerry Wass >
> wrote:
>
>>>> The main reason being--1 gal mogas= 7.422 lbs.
>>>> 1 gal avgas= 6.978 lbs.
>
>>> Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and
>
>> The Avgas weighed 168.3 gms/250cc---The Mogas weighed 179.0gm/250cc----
>>
>> Please let me know If I made any mistakes in the conversion----If not,
>> I'll re-weigh two more samples tomorrow..
>
> Plugging your avgas numbers into my conversion software, I get 0.371
> lb / 0.066 gal for your measurements ... which my calculator gives as
> 5.62 lb.gal. I didn't run the mogas.
>
> One of us has bad conversion data, maybe both of us.
>
> George
Doing the simplest conversion---168.3/250.0--= sp.gr.of 0.6732..
0.6732X 8.34(#/gal for h2o)= 5.614 #/gal for Avgas--agreeing with
you--but isn't right---I'm gonna weigh things again--might have been off
on my tare weight. Jerry
Barnyard BOb
May 31st 07, 04:56 PM
Jerry Wass wrote:
>
>Doing the simplest conversion---168.3/250.0--= sp.gr.of 0.6732..
>
>0.6732X 8.34(#/gal for h2o)= 5.614 #/gal for Avgas--agreeing with
>you--but isn't right---I'm gonna weigh things again--might have been off
>on my tare weight. Jerry
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
I don't keep avgas at my house. However....
Weighing 250 cc of 60 degree F. mogas = 190 grams
Specific gravity = 190/250cc = 0.76
0.76 x 8.34 = 6.3384....
MOGAS = 6.3384 lb/gal @ 60 degrees F.
More than close enough for GW Bush gov't work!
Barnyard BOb - definitely beating YOUR dead horse 8-)
jerry wass
June 1st 07, 02:25 PM
Barnyard BOb wrote:
> Jerry Wass wrote:
>
>> I agree that a gallon of Mogas has more btu's than a gallon of Avgas
>>
>>
>> The main reason being--1 gal mogas= 7.422 lbs.
>> 1 gal avgas= 6.978 lbs.
>>
>> Q.E.D.
> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>
> Not true, Jerry.
>
> Ready Reference Files
>
> Weight of One Gallon (U.S.) of Water, Gasoline, and Ethanol
>
> 1 gallon of water equals 8.33 lbs.
> 1 gallon of gasoline equals 5.8 to 6.5 lbs.
> 1 gallon of ethanol equals 6.59 lbs.
>
> Source: U.S. Dept. of Energy. Fuel From Farms: a Guide to Small Scale
> Ethanol Production. May 1980. Page D-3.
>
> Verified by: JT, 9/98
>
> Disclaimer:
> While the Library has verified the information presented in these
> files in what it considers to be reliable and authoritative sources,
> it cannot take responsibility for nor guarantee the accuracy of the
> information presented.
>
> ---------------------------------------
>
> Avgas
> From Wikipedia, the free encyclopedia
>
> Properties
> Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and
> this density is commonly used for weight and balance computation.
> Density increases to 6.40 lb/US gallon at -40 °C, and decreases by
> about 0.5% per 5 °C increase in temperature.[3]
>
Yes, I'm beginning to doubt my measurements, haven't had time to repeat
them yet. Jerry
Roger (K8RI)
June 2nd 07, 06:23 AM
On Thu, 31 May 2007 10:56:21 -0500, Barnyard BOb
> wrote:
>
>Jerry Wass wrote:
>
>>
>>Doing the simplest conversion---168.3/250.0--= sp.gr.of 0.6732..
>>
>>0.6732X 8.34(#/gal for h2o)= 5.614 #/gal for Avgas--agreeing with
>>you--but isn't right---I'm gonna weigh things again--might have been off
>>on my tare weight. Jerry
>-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>
>I don't keep avgas at my house. However....
>
>Weighing 250 cc of 60 degree F. mogas = 190 grams
>
>Specific gravity = 190/250cc = 0.76
>
>0.76 x 8.34 = 6.3384....
>
>MOGAS = 6.3384 lb/gal @ 60 degrees F.
>
>More than close enough for GW Bush gov't work!
A more relevant number is the BTUs per gallon which translaes into MPG
for a given engine.
Automotive gas in California is about 111,500 BTU while E85 is about
81,000, or 72% Straight Ethenol is roughtly 60% or 66,600 BTU.
Alcohol costs more while giving much less energy and MPG. IOW just
going from straight gas to E85 a trip that takes 50 gallons of gas
will take at least 69.5 gallons of E85.
Given todays car gas prices of basically $3.20 per gallon (it's near
$3.50 in michigan) if we take that 50 gallons of gas for a trip at
$3.50 it's 175 USD. Given the same price for E85 (which is actually
more expensive) we come up with $243.25, or an extra $68.25 for the
same trip using E85.
Alternative fuels are in general more expensive to use or implement
than gas. For those fuels to become viable alternatives the cost of
gas is going ot need to go to at least $3.50 a gallon and stay there.
Except for small scale implementation, Hydrogen is much more
expensive.
I spent some time with a consulatant a couple weeks back. His
conclusion for me to go a combination of active and passive solar
power would easily run bet ween $30,000 and $50,000 for this small
home. Yes, I could sell power back to the power company, BUT our rates
are about 8 cents per KWH whichmakes for a very long pay back if I
don't have to purchase any power. Add to that, maintenance on the
syatem and it really starts to get expensive.
Barnyard BOb
June 2nd 07, 07:00 AM
"Roger (K8RI)" wrote:
>>
>>MOGAS = 6.3384 lb/gal @ 60 degrees F.
>>
>>More than close enough for GW Bush gov't work!
>
>A more relevant number is the BTUs per gallon which translaes into MPG
>for a given engine.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Roger,
You are very, very late to this party.
Btu/gal is not only old news, if you follow this thread back....
but of no interest to the 'victims' beating this horse dead!
Sorry. 8-)
- Barnyard Bob - lord luva duck
Roger (K8RI)
June 2nd 07, 07:41 AM
On Sat, 02 Jun 2007 01:00:31 -0500, Barnyard BOb
> wrote:
>
> "Roger (K8RI)" wrote:
>
>>>
>>>MOGAS = 6.3384 lb/gal @ 60 degrees F.
>>>
>>>More than close enough for GW Bush gov't work!
>>
>>A more relevant number is the BTUs per gallon which translaes into MPG
>>for a given engine.
>-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>
>Roger,
>You are very, very late to this party.
>
>Btu/gal is not only old news, if you follow this thread back....
>but of no interest to the 'victims' beating this horse dead!
I've been following the thread Bob, but the only thing I could find
relevant is energy per unit. The only time I care about weight or spg
is when figuring out how much I can carry. <:-0)
>
>Sorry. 8-)
>
>
>
>- Barnyard Bob - lord luva duck
Barnyard BOb
June 2nd 07, 10:23 PM
"Roger (K8RI)" wrote:
> Barnyard BOb wrote:
>
>>
>> "Roger (K8RI)" wrote:
>>>
>>>A more relevant number is the BTUs per gallon which translaes into MPG
>>>for a given engine.
>>-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>>
>>Roger,
>>You are very, very late to this party.
>
>I've been following the thread Bob, but the only thing I could find
>relevant is energy per unit. The only time I care about weight or spg
>is when figuring out how much I can carry. <:-0)
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Hi Roger,
Do these old posts of mine not address your topic of concern?
-------------
MAY 29, 2007
From Wikipedia, the free encyclopedia:
Energy content
Gasoline contains about 34.6 megajoules per litre (MJ/l) or 131 MJ/US
gallon. This is an average, gasoline blends differ, therefore actual
energy content varies from season to season and from batch to batch,
as much as 4% more or less than the average, according to the US EPA.
Fuel type BTU/US gal Research octane
Regular Gasoline 125,000 Min 91
Aviation gasoline 120,200
BTU/US gal
Gasohol (10% ethanol + 90% gasoline) 120,900
( Research octane) 93/94
- Barnyard BOb -
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
MAY 29, 2007
Peter,
After reading your earlier post and having held similar views for
many years, I thought something like this might be of interest.
FWIW, my rule of thumb...
The cruder the fuel, the more btu/gal.
i.e., diesel blows away gasoline @ 138,700 btu/gal
Jet Fuel: Kerosene* 125,800 btu/gal
*Chevron Products Company 2000
- Barnyard BOb - the devil's in the details
-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=-=-=-=-=-=-
MAY29, 2007
Jerry,
Your ORIGINAL ARGUEMENT WAS....
"Hate to disagree. but there are more BYU's in a GALLON of Avgas than
in a GALLON of Mogas. Why?? Avgas weighs more per Gallon..."
Weight of fuel is irrelevant when it comes to btu/gal....
assuming your BYU reference was meant to be btu.
Btu/gal is a VOLUME measurement, not one of weight.
Thank you for your time and patience.
- Barnyard BOb -
Jerry,
Your ORIGINAL ARGUEMENT WAS....
"Hate to disagree. but there are more BYU's in a GALLON of Avgas than
in a GALLON of Mogas. Why?? Avgas weighs more per Gallon..."
Weight of fuel is irrelevant when it comes to btu/gal....
assuming your BYU reference was meant to be btu.
Btu/gal is a VOLUME measurement, not one of weight.
Thank you for your time and patience.
- Barnyard BOb -
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
MAY 29, 2007
Jerry,
I have purposely distanced myself from weight specifics
since my sources state energy content BY VOLUME,
which is the convenient way we buy fuel at the pump.
Found another web site stating values by GALLON, not weight.
[No idea how accurate these values are.]
http://www.jwiwood.com/faq/conversion.html
Too bad they make no reference to avgas.
For grins.....
1 gallon of crude oil ... 138,095 Btu
1 gallon of kerosene or light distillate oil ... 135,000 Btu
1 gallon middle distillate or diesel fuel oil ... 138,690 Btu
1 gallon residential fuel oil ... 149,690 Btu
1 gallon of gasoline ... 125,000 Btu
1 gallon of ethanol ... 84,400 Btu
P.S.
If these figures are reasonably accurate...
It takes MORE than a gallon of crude to produce a gallon of diesel.
Double ditto for residential fuel oil.
- Barnyard BOb -
Roger (K8RI)
June 4th 07, 05:41 PM
On Sat, 02 Jun 2007 16:23:53 -0500, Barnyard BOb
> wrote:
>
>"Roger (K8RI)" wrote:
>
>> Barnyard BOb wrote:
>>
>>>
>>> "Roger (K8RI)" wrote:
>>>>
>>>>A more relevant number is the BTUs per gallon which translaes into MPG
>>>>for a given engine.
>>>-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>>>
>>>Roger,
>>>You are very, very late to this party.
>>
>>I've been following the thread Bob, but the only thing I could find
>>relevant is energy per unit. The only time I care about weight or spg
>>is when figuring out how much I can carry. <:-0)
>
>-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>
>Hi Roger,
>
>Do these old posts of mine not address your topic of concern?
>
Not tht I can find.
I was addressing the energy content in pure Methenol and E85 compared
to gas. Near as I can tell, the rest of the thread compared Gasahol
(10% alcohol), avgas, car gas, and kerosean, or did I miss something?
I rememember I did make a mistake one time<:-))
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