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It costs 6kW to refine a single gallon of gasoline. We can shift our energy away from the refineries as their demand tapers off.

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I'd say that number is a bit suspect as the amount of work to refine Texas Sweet (WTI) vs the more difficult to refine oil you find from Venezuela or the entire Middle East (it is heavier or more "sour") is vastly different. This gives a primer on it:

http://canaryusa.com/crude-oil-refinery-primer/

>> the entire Middle East

Except for Saudi sweet. There is plenty of very high quality oil in Saudi Arabia, which is no doubt in the heart of the "middle east". (Iraq and the UAE also produce sweet crude.) The really nasty stuff, the really energy-intensive gunk, is the tarsand bitumen from Canada. Saudi oil is positively green in comparison.

https://en.wikipedia.org/wiki/Sweet_crude_oil

>> The term sweet originates from the fact that a low level of sulfur provides the oil with a mildly sweet taste and pleasant smell.

I wonder who took it upon themselves to taste all the different kinds of crude oil to classify them by flavor... Job for a grad student?

Wasn't oil used medicinally for a while after its discovery? Not ingested, but rubbed on your skin to ease joint pain?

More than for "a while". Oil was discovered hundreds, thousands, of years ago. It used to seep out of the ground in many places (See the opening sequence of The Beverly Hillbillies). Only once we started pumping it did all the surface seeps dry up.

Fun fact, it still does, in 2019, seep out of the ground in downtown Los Angeles. Literally on the miracle mile sits the La brea Tarpits. You can see the pond with oil bubbling out of the water. If you're ever in Los Angeles, it is a very memorable thing to visit.

https://tarpits.org/

Oil prospectors invented the terms when they were combing the backcountry looking for oil, without access to proper chemical labs.

I just found this humorous clip of the Trailer Park Boys, which alludes to the tastes of various types of gasoline: https://youtu.be/RXtePW4v8zs

Much to most of KSA's oil is full of heavy sulfur content and is considered sour. Virtually all of the Texas oil is considered sweet. WTI (Texas Sweet) is basically the benchmark for the best oil. Some of the best oil (sweet) in the middle east traditionally was from Libya, but since team america world police took out Gadaffi it has been a mess there. I'm not very familiar with Canadian oil as we don't need much of it here.

https://www.oilandgasmiddleeast.com/drilling-production/3496...

""" Saudi crude is generally a mix of heavy to medium sour oil, which is generally high in sulfur and yields a decent amount of residual fuel and vacuum gasoil. """

https://en.wikipedia.org/wiki/Sour_crude_oil

""" The major producers of sour crude oil include ... Saudi Arabia """

I wasn't meaning they have no sweet light crude oil, only that it is the overwhelming minority of what they have.

https://www.reuters.com/article/us-middle-east-crude/analysi...

6kWh to refine a gallon of gasoline? That's not a bad conversion rate given that the energy in a gallon of gasoline is 33-34kWh.

I suppose you'd want to include transportation 'costs', and off gassing (edit: I meant flaring), etc, etc.

The typical internal combustion engine is only ~30% efficient, getting only ~10 kWh of energy out of that gallon.

Indeed. That does not, however, impact the actual energy available in a gallon of gasoline.

Technically the 6kWh of energy spent on refining (or any other work) is itself subject to inefficiencies in generation, transmission, etc. It would also suffer from inefficiencies in the electrical storage and motive portions of an electric vehicle as well. And at the end of the day even if there were perfect 100% conversion it would still only be 6kWh of energy available vs 33-34kWh.

I think the point is that the energy inputs required to produce a gallon of gasoline could approximately power an EV vehicle roughly the same distance that a typical ICE could go on a gallon of gasoline. A quick google search seems to back that up.

I'm not sure I'm seeing the same comparisons that you are regarding travel distances. A Tesla Model 3 uses 24-29 kWh/100 miles (depends on drive/battery options) which would be 4-5 gallons of gasoline. That would be 20-25MPG assuming the 10kWh/gallon ICE which is pretty low for a mid-sized sedan. An Accord hybrid pulls around 48MPG, while a Dodge Charger Hellcat SRT manages an EPA combined 23MPG (hardly a typical ICE given that it puts out 707 horsepower).

The average MPG in the US is around 25mpg[1]. So assuming that 6 kWh of electricity from the grid (big assumption, see below) is used to refine a gallon of gas, then it seems like the math pencils out. Of course the MPG average includes trucks and SUVS, etc, so not a perfect comparison but very much in the ballpark.

Regarding the 6kWh number, I have been having a lot of trouble confirming it. Some stuff I have read says that refineries are major consumers of grid electricity. Others claim that they can produce most of their energy needs from the oil distillates on-site. My best guess is that it probably depends on how old the refinery is, because it seems like the older reports/estimates tend to mention the electricity consumption, whereas the newer ones mention the 'on-site' energy generation/consumption. I think a lot of the energy demand of the refinery is used for heating, so burning the oil distillates would be way more efficient than using grid electricity for that. So, it may just be the case that older refineries are way less efficient than newer ones, and the 'EV vs ICE' comparison depends on how modern the refineries are in your area.

[1] https://www.reuters.com/article/us-autos-emissions/u-s-vehic...

The Model 3 gets 126 MPGe.

That is incorrect. You have to compare the 6kWh where it is used (at the refinery) and the 10kWh available on the vehicle. Both numbers already include the inefficiencies and therefore are comparable.

Which gives to a mere 4Wh of additional power extracted from gasoline.

A "mere 4kWh of additional power" is 67% additional power.

Pretty lousy for something that we consider a primary source of energy.

That's true, but it does ignore the waste heat, which in winter months is used to warm the passenger compartment. It's one thing EVs do have working against them, though it doesn't make up for the huge efficiency gain EVs have overall.

I know several coworkers who prefer to drive their EV in the winter because it heats up quicker (waiting ~5 minutes for the ICE to warm up the car vs. an active electric heater that starts right away)

Yes, but they're having to actively use battery power to do that, instead of just passively using waste heat from the ICE engine. So this greatly reduces their range. It probably works out fine for them because the car's maximum range is probably much greater than their commute distance, so they probably have battery capacity to spare and burning some of it on heat isn't a big deal as it gets recharged at home every night (and maybe also at work). If they had more "range anxiety", however, they probably wouldn't be so eager.

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