7.5 kWh of electricity to produce a gallon of gasoline?

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indyflick said:
So Rik, if refining gasoline is so efficient, what accounts for the fact that petroleum refineries in the US in 2005 used 48,891,000,000 kWh of electricity?
Well, as I come off the southbound Benicia bridge at night I see what looks like a hundred acre forest all lit up like Christmas trees off to the right. I think that's a Shell refinery. That's got to be a huge amount of electricity spent lighting the sky, and unless they use photons reflected off smoke plumes in the refining process, I don't think it counts as part of the kilowatts per gallon of gas.
 
indyflick said:
So Rik, if refining gasoline is so efficient, what accounts for the fact that petroleum refineries in the US in 2005 used 48,891,000,000 kWh of electricity?
indyflick, assuming that number is correct, that's 1.2% of the 4,055,423,000,000 kWh of electricity produced in the US in 2005.

In 2005, US oil refineries produced 17,800,041 B/d of refined products = 6,497,014,965 B/yr = 272,874,628,530 gal/yr.

48,891,000,000 kWh per yr / 272,874,628,530 gal per yr = 0.179 kWh per gallon

It's not even close to 7.5 kWh per gallon.

Source for 2005 US production of refined products and electricity: US Energy Information Administration http://tonto.eia.doe.gov/cfapps/ipdbproject/IEDIndex3.cfm
 
Rik said:
indyflick, assuming that number is correct, that's 1.2% of the 4,055,423,000,000 kWh of electricity produced in the US in 2005.

In 2005, US oil refineries produced 17,800,041 B/d of refined products = 6,497,014,965 B/yr = 272,874,628,530 gal/yr.

48,891,000,000 kWh per yr / 272,874,628,530 gal per yr = 0.179 kWh per gallon

It's not even close to 7.5 kWh per gallon.

Rik, are you messing with us? You have the formula backwards. It would be:
272,874,628,530 gal per yr / 48,891,000,000 kWh per yr = 5.58 kWh per gallon. Of course this is just the refining process consumption of electricity. When the entire supply chain is considered, I suspect it would be well above 7.5 kWh. Some say over 12 kWh. I'm starting to view gasoline as simply a combustible store of consumed electricity.
 
UPDATE... I divided incorrectly in the last step. As pointed out by Rik and evnow, this analysis is not correct. This analysis actually indicates 22,587,642,000 kWh / 132,488,160,000 gallons of gasoline = 0.17 kWh per gallon of gasoline in the refining process.

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BTW, the 272,874,628,530 gal per yr is total refined product from the refinery. In my analysis a few pages back, I applied a 46.2 percentage to both the electricity consumed and to account for the percentage of gasoline produced versus all other refined product.

Here's the analysis again:

Electricity consumption by petroleum refineries in the US in 2005 was 48,891,000,000 kWh
http://www.nationmaster.com/graph/ene_e ... ies#source

Gasoline composed 46.2% of all US refined oil products in 2005
http://tonto.eia.doe.gov/dnav/pet/pet_p ... _pct_a.htm

Therefore, we take 46.2% of the total electricity used by the US refineries in 2005 for galoline production. So that would be 22,587,642,000 kWh of electricity. (48,891,000,000 kWh * .462)

In 2005 US refineries produced 132.4 billion gallons of gasoline
http://www.eia.gov/dnav/pet/hist/LeafHa ... frpus2&f=w

Download the spreadsheet and use the 2005 data on gasoline production. The data is the weekly U.S. Refinery and Blender Adjusted Net Production of Finished Motor Gasoline (Thousand Barrels per Day). So you need to add up the weekly totals, multiply by 7 to get the full weeks, multiply by 1000 (data is thousands), and multiply by 42 because there are 42 gallons in a barrel. That gets you to 132,488,160,000 gallons.

132,488,160,000 gallons of gasoline / 22,587,642,000 kWh = 5.86 kWh of electricity consumed for every gallon of gasoline produced in the US in 2005.
 
indyflick said:
Rik, are you messing with us? You have the formula backwards. It would be:
272,874,628,530 gal per yr / 48,891,000,000 kWh per yr = 5.58 kWh per gallon.

No - Rik is right.

Let us say 10 Gallons of gas requires 100 kwh. So how much does 1 Gallon need ? 100 kwh / 10 Gallons = 10 kwh / 1 gallon. Look at the units to tell you how to calculate.

Since a lot of the refineries even produce their own electricity (apart from using NG etc) - this would be a small amount. Need to look at total energy consumption as I've been saying.
 
indyflick said:
132,488,160,000 gallons of gasoline / 22,587,642,000 kWh = 5.86 kWh of electricity consumed for every gallon of gasoline produced in the US in 2005.
Look at the units you are working with. You calculated gallons per kWh, while it's kWh per gallon we're interested in.
 
No - Rik is right.

Let us say 10 Gallons of gas requires 100 kwh. So how much does 1 Gallon need ? 100 kwh / 10 Gallons = 10 kwh / 1 gallon. Look at the units to tell you how to calculate.

Yep, I mangled it. 1000 apologies.

Nissan.... PLEASE tell us how you derived the 7.5 kWh statistic.
 
evnow said:
Since a lot of the refineries even produce their own electricity (apart from using NG etc) - this would be a small amount. Need to look at total energy consumption as I've been saying.
I found a document that shows all the refineries in California and their on-site production and usage of electricity. See Table 3-1 here http://www.eia.doe.gov/emeu/steo/pub/special/california/june01article/carefinery.html

For 92% of California's refining capacity (data for the other 8% is not reported)
Total Electricity Consumption: 913 MW
Co-generation Capacity: 1038 MW (= electricity produced by refineries)

Consumption per day: 913 MW * 1000 kW/MW * 24 h/day = 21,912,000 kWh/day

So if in the future all of California's refineries were shut down after a conversion to non-petroleum based fuels, it might not create any additional electricity capacity in the state since the refineries' co-gen units would probably shut down as well. This would free up the natural gas that is used by the co-gen units to make electricity and steam, as well as the natural gas that is burned in refinery heaters and used to manufacture hydrogen.

Total capacity of these California refineries: 1840 mbpsd = 1,840,000 B/day = 77,280,000 gal/day

Electricity used per gallon: 21,912,000 kWh/day / 77,280,000 gal/day = 0.284 kWh / gal

There is also in Table 3-3 a breakdown of electricity usage for each type of unit in a typical 100,000 B/d = 4,200,000 gal/d oil refinery, which adds up to 732,397 kWh/d.

Electricity used per gallon: 732,397 kWh/d / 4,200,000 gal/d = 0.174 kWh / gal

So either way, it's still well under 1 kWh/gal.
 
indyflick said:
Nissan.... PLEASE tell us how you derived the 7.5 kWh statistic.
Nissan botched it with this number, but I'll give them a pass since they are a car company and not an oil company. I'm assuming that for the calculations that matter to their core business, Nissan knows what they are doing. Besides, it was probably just the Nissan marketing guys who did this. I don't believe that any Nissan engineer would have made this mistake.
 
Rik said:
Nissan botched it with this number....

They probably picked it from some study - but is probably presented wrong. I won't be surprised if the total energy input to get oil (from well to tank) is 7.5 kwh / gallon.
 
evnow said:
They probably picked it from some study - but is probably presented wrong. I won't be surprised if the total energy input to get oil (from well to tank) is 7.5 kwh / gallon.

To your earlier point, at the very least, we need to look at the combined electricity kWh as well as NG energy consumed at the refinery. Then the statistic would be stated as kWh of energy used to refine a gallon of gasoline. It was just looking to me that just their electricity consumption on its own was high enough to make the case.
 
evnow said:
Rik said:
Nissan botched it with this number....

They probably picked it from some study - but is probably presented wrong. I won't be surprised if the total energy input to get oil (from well to tank) is 7.5 kwh / gallon.

The number is going to be significantly different if the well is in East Texas and the refinery is in Texas City as compared with a refinery in Louisiana and a source well in Iraq or Saudi Arabia.

And the energy use jumps more if we expand to other factors that allow the oil to flow - destroyers and jets burn a LOT of fuel...
http://www.iags.org/n1030034.htm
NDCF report: the hidden cost of imported oil

The National Defense Council Foundation (NDCF), an Alexandria, Virginia-based research and educational institution has completed its year-long analysis of the “hidden cost” of imported oil. The NDCF project represents the most comprehensive investigation of the military and economic penalty our undue dependence on imported oil exacts from the U.S. economy. Included in this economic toll are:

Almost $49.1 billion in annual defense outlays to maintain the capability to defend the flow of Persian Gulf Oil – the equivalent of adding $1.17 to the price of a gallon of gasoline;
The loss of 828,400 jobs in the U.S. economy;
The loss of $159.9 billion in GNP annually;
The loss of $13.4 billion in federal and state revenues annually;
Total economic penalties of from $297.2 to $304.9 billion annually.
If reflected at the gasoline pump, these “hidden costs” would raise the price of a gallon of gasoline to over $5.28, a fill-up would be over $105.

One striking figure was the cost of the periodic oil shocks the U.S. has experienced over the past three decades which NDCF estimates at from over $2.2 Trillion to almost $2.5 Trillion.

Prior to completion the study underwent an exhaustive peer review by a panel comprised of seventeen individuals with a broad range of expertise including representatives from government, industry and major environmental organizations.

In addition to detailing the costs of America’s import dependence, the NDCF report also outlines the benefits of shifting the U.S. transportation sector to non-petroleum derived fuels.
 
evnow said:
They probably picked it from some study - but is probably presented wrong. I won't be surprised if the total energy input to get oil (from well to tank) is 7.5 kwh / gallon.
Besides oil refining, the other major use of energy in a well-to-tank analysis is oil production (getting it out of the ground). The transportation and marketing of oil and refined products is relatively small by comparison.

The same source of electricity used to refine oil also has some numbers for oil extraction here:
http://www.nationmaster.com/graph/ene_ele_con_by_cru_pet_fie-electricity-consumption-crude-petroleum-fields
This indicates 33.636 billion kWh to extract oil in the US in 2005.

In 2005, the US produced 8,321,800 b/day = 349,515,600 gal/day = 127,573,194,000 gal/yr of crude oil. (source: US EIA)

So the electricity usage per gallon for oil extraction in the US = 33.636 billion kWh/yr / 127,573,194,000 gal/yr = 0.26 kWh/gal. So it still well under 1 kWh/gal. I don't know how much of this electricity comes from byproducts of petroleum production but it might be a lot. I don't believe they run high voltage power lines out to offshore oil platforms, for example. I think they generate their own electricity on site using byproducts of petroleum production.

If we added up all electricity used to take oil from well to tank it's going to be under 1 kWh/gal. Not anywhere near 7.5 kWh/gal.

In the US, a tiny fraction of the petroleum-based fuels produced is burned to make electricity, and this produces about 54.2 billion kWh/yr of electricity. In some other countries a larger fraction of oil products is used for electricity production. The US exports some petroleum-based fuels that are burned in other countries to make electricity.

I think a more interesting metric would be the amount of natural gas used to take oil from well to tank. We'd need to add up the natural gas used to make electricity and steam, and the natural gas used in fired heaters. We could compare this how much electricity could be delivered to EV batteries if all that natural gas was instead used to make electricity, though we need to subtract the 54.2 billion kWh/yr produced from burning refined fuels in the US and however much electricity is created from the petroleum coke, etc. that the US exports to other countries. If we do that I'm believe the bottom line will still work out to a lot less than 7.5 kWh/gal.

The natural gas used as feedstock in the manufacture of hydrogen for hydrocrackers and hydrotreaters in oil refineries would not "count" for this purpose because it isn't a "fuel" used in a well-to-tank calculation. Hydrogen is a raw material that is used to make refined products just as the petroleum is a raw material used to make refined products.
 
How shall we account for the amount of finished gasoline we import from Europe?

Do any of the record keepers track how much energy is used on a drilling and/or production rig?

If the goal of the exercise is simply to find some numbers to discredit the 7.5 kWh number, than you've done it. If the goal is to understand well to pump energy use we might want to put away the calculator and start by defining the bounds of the problem first.

Or am I completely missing the point?
 
AndyH said:
How shall we account for the amount of finished gasoline we import from Europe?

Do any of the record keepers track how much energy is used on a drilling and/or production rig?

If the goal of the exercise is simply to find some numbers to discredit the 7.5 kWh number, than you've done it. If the goal is to understand well to pump energy use we might want to put away the calculator and start by defining the bounds of the problem first.

Or am I completely missing the point?
Andy, I don't think you are missing the point. Depending on what the question is, we can bound the problem differently. And it does get complicated.

For me personally, the interesting question is the transition of the economy away from petroleum, and how that would impact energy balances. I have seen studies suggesting that the existing electrical generating capacity in the US is already adequate if the ICE light transportation fleet was replaced with BEV vehicles, so long as we charge our BEV's during off peak hours. NG fired electrical generators that normally slow down or shutdown during off peak hours would need to keep running. We would need to develop substitutes for other refinery products, and aircraft fuels will still need to be high energy density liquids.
 
AndyH said:
If the goal of the exercise is simply to find some numbers to discredit the 7.5 kWh number, than you've done it. If the goal is to understand well to pump energy use we might want to put away the calculator and start by defining the bounds of the problem first.
I kinda started this thread with the following goal.
indyflick said:
I would like to know if Nissan have a white paper available which shows how they derived the "7.5 kWh of electricity to produce a gallon of gasoline" figure. There are some on the Internet who say it's actually more like 12 to 13 kWh. Other say it's 5 kWh. Still others say its less than 1 kWh.
Not trying to discredit Nissan, just trying to understand their analysis. How did Nissan bound the problem? What were their sources and assumptions. Just looking for a simple white paper.
 
Check this out lots of information.

http://www.teslamotorsclub.com/showthread.php/4392-Carbon-footprint-clarification?p=48703#post48703


refining the oil to gasoline
85.5% Petroleum Refining Efficiency: 340 ppm S Conventional Gasoline
From 2001 GM Global Alternative Propulsion Center (GAPC) study done by ANL.

http://www.transportation.anl.gov/pdfs/TA/166.pdf

83.0% Petroleum refining and distribution efficiency
Electric and Hybrid Vehicle Research, Development, and Demonstration Program; Petroleum-Equivalent Fuel Economy Calculation (published in year 2000)

http://www.epa.gov/EPA-IMPACT/2000/June/Day-12/i14446.htm
 
Rik said:
AndyH said:
How shall we account for the amount of finished gasoline we import from Europe?

Do any of the record keepers track how much energy is used on a drilling and/or production rig?

If the goal of the exercise is simply to find some numbers to discredit the 7.5 kWh number, than you've done it. If the goal is to understand well to pump energy use we might want to put away the calculator and start by defining the bounds of the problem first.

Or am I completely missing the point?
Andy, I don't think you are missing the point. Depending on what the question is, we can bound the problem differently. And it does get complicated.

For me personally, the interesting question is the transition of the economy away from petroleum, and how that would impact energy balances. I have seen studies suggesting that the existing electrical generating capacity in the US is already adequate if the ICE light transportation fleet was replaced with BEV vehicles, so long as we charge our BEV's during off peak hours. NG fired electrical generators that normally slow down or shutdown during off peak hours would need to keep running. We would need to develop substitutes for other refinery products, and aircraft fuels will still need to be high energy density liquids.

Actually, it isn't complicated at all when we use pvs or other renewable resources to charge our cars. As the saying goes, "Keep it simple." :D
 
Extensive WellToWheel analysis for Europe.

http://ies.jrc.ec.europa.eu/WTW

Specifically see this doc : http://ies.jrc.ec.europa.eu/uploads/media/WTT_Report_010307.pdf

Section 3.1 deals with Oil production, transportation & refining. Petrol uses 14% and diesel 16% of energy from well to tank or about 5 kwh of energy.
 
evnow said:
Extensive WellToWheel analysis for Europe.

http://ies.jrc.ec.europa.eu/WTW

Specifically see this doc : http://ies.jrc.ec.europa.eu/uploads/media/WTT_Report_010307.pdf

Section 3.1 deals with Oil production, transportation & refining. Petrol uses 14% and diesel 16% of energy from well to tank or about 5 kwh of energy.
Interesting report, thanks for the pointer. I have a couple of questions. First, I assume you calculated this from 14% of 36.6 kWh per gallon of gasoline, correct? That would be 5.124 kWh. But how did you derive the 14%? It looks like 8% in the chart, what am I missing?

Second, I believe MJ/MJ means the megajoules of energy required to produce an energy product which has one megajoules worth of stored energy, correct? The study says (on page 17) that gasoline MJ/MJ is 0.08. I read in this article that's it's more like 0.20 to 0.25 and gasoline from shale is 0.56 to 0.87!
 
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