How much energy does it take to produce a gallon of gasoline?

[NeilBlanchard]

How much electricity and natural gas is used to explore for petroleum, extract it, transport it, refine to gasoline (or diesel, etc.), transport it again, and then pump it into your tank?

Some sites I've found that are trying to answer this question:

Gasoline and Oil

Electricity vs Oil - Planet Better Place

Just to refine the oil to make gasoline, it may take 3kWh or 7.5kWh (plus many therms of natural gas?), so for the refining alone, it could be used to move an EV 30-50 miles -- without using the gasoline!

Can you confirm/deny/correct these numbers?

[Christ]

Answer: Too much.

Moving on... :P

I keed...

[Piwoslaw]

Crossposting:
Fuel production efficiency

[NeilBlanchard]

I have emailed the Union of Concerned Scientists; and hopefully I hear back from them?

[NeilBlanchard]

The point is that grams of carbon per mile for gasoline is usually just counting the carbon contained within the gasoline -- and leaves out the carbon it took to obtain the oil and make it into gasoline; which may be as much as 50% as much as what is in the gasoline.

If it takes 7.5kWh of electricity (plus some natural gas, too) to refine one gallon of gasoline from petroleum -- then why don't we just use the 7.5kWh directly in an EV?

7.5kWh of electricity could move and EV anywhere from 30 to 60 miles or so.

If you put the gasoline in a car that get the national average of 25mpg, you only go 25 miles -- and you should also count the 7.5kWh against that, too. Which lowers the MPGe of the ICE car even further; and it raises the carbon emission to levels far higher than the EV, obviously.

And that is only the energy it took to refine the petroleum -- in reality, you should also count all the other energy inputs to produce the gasoline!

So, an EV is going to be much, much more efficient than a ICE. And using a lot of EV's will likely reduce the overall load on the electrical grid.

[bgd73]

way back when they had steam power doing all the big work.
up to 24 pumps hooked up to a makeshift crank spinning around, mechanical dangers everywhere, boilings into 900F making fuel.

whatever the "watt" today, it is better than ever.


I find astonishing..even in that link about consumption...the fantastically ridiculous leap into doubling consumption exactly coincides with that idiot called fuel injection, making its sloppy butt way into america and the world....why does noone focus on the real facts?

even the EV world is a wild tangent of fantasy, hardly maximizing itself into a heavier purpose for reality...not to menmtion, the by product of using the energy in the long term.Even folks in old cars have had to go einstien themselves to stop the little mysteries...still not conquered....the market and science has to focus on the real consumption.

[Piwoslaw]

Originally Posted by NeilBlanchard

If it takes 7.5kWh of electricity (plus some natural gas, too) to refine one gallon of gasoline from petroleum -- then why don't we just use the 7.5kWh directly in an EV?

7.5kWh of electricity could move and EV anywhere from 30 to 60 miles or so.

That is one of the best reasons for ditching the ICE in favor of electric that I've ever read.

[Christ]

Ok, so thinking back to high school, and the "butterfly" effect that occurs in production circles:

In order to make a gallon of fuel, you need to extract the raw material, which takes fuel.

Then, you need to move the raw material, which takes fuel.

Then, you need to refine the raw material into usable substrates, which takes yet more fuel.

Production of electricity is a lossy operation, using yet even more fuel.

All of the fuel you just used to get fuel was also, at one point, raw, and had the same requirements.

The effect isn't just singular, it's multi-generational. Each KW of energy you use had to come from a previously used KW of energy which came from a previous KW, etc.

[RobertSmalls]

Originally Posted by Christ

The effect isn't just singular, it's multi-generational. Each KW of energy you use had to come from a previously used KW of energy which came from a previous KW, etc.

This reminds me of a fun fact: the green energy infrastructure of tomorrow will be built on the brown energy of today. How much would it cost to build a wind farm, hauling 150' blades and 60-ton nacelles, using battery-electric trucks? And what if the electricity to charge those trucks came from coal extracted using battery-electric mining equipment and delivered by electrified heavy rail?

[RobertSmalls]

Originally Posted by NeilBlanchard

7.5kWh of electricity could move and EV anywhere from 30 to 60 miles or so.

If you put the gasoline in a car that get the national average of 25mpg, you only go 25 miles -- and you should also count the 7.5kWh against that, too. Which lowers the MPGe of the ICE car even further; and it raises the carbon emission to levels far higher than the EV, obviously.[/B]

This is an unfair comparison. An "average" person driving an electric midsized sedan or SUV at 75mph with the A/C on would not be getting 125-250Wh/mi. If you wanted a fair comparison, the best we have available would probably be a Prius (or a PHEV converted Insight or Tahoe?) driven in EV mode, versus the same car driven the same speed on gasoline.





I found the following source: http://www1.eere.energy.gov/industry...fs/profile.pdf
with the relevant info starting on p 19. It mentions that refining represented 7% of the US' energy consumption in 2002. Unfortunately, it doesn't mention how much energy and non-energy products refineries put out that year, so it doesn't give an efficiency number. But it's still worth reading:

64% of the energy used in refining comes from the refining process itself. When refinery gas is burned in a turbine to generate electricity that is used for refining, it is completely wrong to assume this energy could be used to power an EV. Without refining, this energy would be unavailable. Another 22% comes from natural gas, which is often, but not always, mined alongside crude. 12%, or 225 billion KWh, comes from purchased electricity. That's enough for 250 million EV's to drive three thousand miles a year, which is a quarter of what is currently driven.

Maybe we could get where we need to be by halving our fleet average fuel consumption AND halving the number of miles driven?

But the output of the refining process is more than just gasoline for cars. There's also non-energy products, diesel, and other fuels. I look forward to the day when trains, trucks, and airplanes run on renewable, low-carbon electricity (which we don't have), but we're not there yet.

If refining took more energy in than it put out, people would stop doing it. But until contradicted by citation of better sources, I'm going to stick with the DoE's numbers, as I mentioned here: 83% efficient.




I'm going to point a finger at the editor of this EVWorld article and accuse him of either intentionally creating a misleading piece, or having a serious disconnect with reality. A fleet of electric vehicles are not viable given our current usage profile, and shutting down the refineries would not come close to providing enough energy to meet our needs. He is also wrong that PHEVs' only role is to "allow the hybrid drivers to relieve some guilt and feel better about themselves". PHEVs are a stepping stone that will drive the development of plug-in infrastructure, and their liquid fuelling capability makes them viable for one-car families. I believe the author also ignored the 80-something percent efficient charger and ~92% efficient battery (if the Wh/mi figures are at the battery rather than the wall).

I stand behind my 13.4KWh/gal energy equivalence figure, with the caveat that energy equivalence is a poor figure of merit. I suggest a weighted average of energy equivalence, cost equivalence, and CO2-equivalence (at 15.1KWh/gal for grid average). I've still been unable to calculate the carbon footprint of the renewable electricity my utility buys for me, but I know it's not zero.