"Fully Charged" - Robert Llewellyn's excellent video podcast on EV's

[NeilBlanchard]

Matt,

887 + 66% = 1472 < 4423 + 17% = 5174

or

887 + 66% = 1472 < 2250 + 17% = 2633

I very much doubt that it only takes 17% of a gallon of gasoline to produce that gallon of gasoline. The would be 33.4 x 17% = 5.7kWh. Nissan says it take 7.5kWh just to refine a gallon of gasoline, let alone all the rest. It might be as high as 10kWh/gallon, all told.

You have not convinced me, that 1472 is greater than 5174 or 2633.

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Doing this sort of math is fairly arbitrary and capricious though, I think. It is like saying that since only ~20 gallons of gasoline and 10 gallons of diesel come from 42 gallons of oil, we need to account for the other 12 gallons by adding 8 to the gasoline and 4 to the diesel... So, for every gallon of gasoline or diesel you burn, you really are burning 1.4 gallons... bogus math!

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The efficiency of the drive train is accounted for in the BTU/mile (or MPGe) number.

EV's are now approaching 80-85% here, while most ICE's are stuck below 20%. Now, you might say; wait Atkinson cycle engines (like in the Prius) are up to 38% efficient! But they can only run at peak efficiency a small part of the time, and by definition, and system that requires a transmission is going to be off peak much of the time. There are transmission losses, and a warm up period, and all that heat production means crappy end use efficiency!

And as I said, the BTU/mile or MPGe number accounts for the efficiency of the entire drivetrain as a system. End use efficiency is what it is all about! If you can only use ~15-20% of the energy you put into the car (on a good day), then that multiplies the inefficiencies of the upstream energy. EV's are so much more efficient in this stage -- look at the heat output!

MPGe tells the story in the vehicle -- X-Prize did this right.

Now, for the carbon footprint, sure you have to take full account of ALL the energy used along the way FOR ALL THE TYPES OF ENERGY, and no matter where it comes from. The electricity used to refine oil *may* come from the process itself, but if the generation of electricity is low efficiency for EV's, then it is the same for the embedded electricity used to refine gasoline -- for purposes of carbon footprint. Ditto for the natural gas used in refining. And for oil extraction, etc.

The article I linked to in the "How much Energy does it take..." thread talks about 1.5% of all California's electricity is being used just for extracting oil. Even if it is really >1%, then that is still enormous. Refining oil takes a lot more than that, plus natural gas, so if you use all that energy for running the EV's directly, then I am fairly certain that you come out way ahead.

[dcb]

can we forget all that baggage and talk about efficiency?

Originally Posted by Patrick

Yes, but one in, what, 1,000,000 people may be willing to build their own car? Definitely not mainstream. And the dolphin doesn't meet crash test requirements or have what most people would consider necessary conveniences.

[Patrick]

Originally Posted by NeilBlanchard

The cost of EV's will come down when they're in mass production.

Agreed. And I hope they do. Soon. But the sales prices out now are all we have to work with.

Originally Posted by NeilBlanchard

And what does the cost of purchase have to do with the efficiency of the vehicle?

Nothing, but the videos posted are rather disingenuous in trying to show that EVs save the owner money, which they don't once the purchase price is included. The purchase price must be included in any cost/benefit analysis.

And don't try to tell me you "saved" enough through EV efficiency to buy a battery pack when you haven't paid off the car price difference yet.

Originally Posted by NeilBlanchard

I doubt very much that the carbon footprint for the Prius's gasoline included the well-to-wheels. Need I mention again, that a car that burns fuel refined from petroleum is consuming as much electricity as the EV is PLUS the gasoline/diesel. 3-5 days "cooking" the oil into fuel takes a lot of additional energy; including electricity (with it's own embedded carbon) and natural gas (which includes it's drilling, transportation, etc.).

Can you tell me how much energy is embedded in gasoline? Because, if you want to be fair, then you have to take this into account.

Edit:

Toyota RAV4 EV: 887 BTU/mile
Toyota Prius: 2250 BTU/mile
Toyota RAV4 Gas: 4423 BTU/mile

(From: Gas Mileage, greenhouse gas emissions, air pollutant emissions and safety ratings of new and used alternative fuel vehicles)

How can 887BTU/mile emit the same carbon as 2250BTU/mile? It is 2.5X higher for the Prius -- is exploring for oil, drilling, transporting, storing, transporting, refining, storing, transporting, storing, and then pumping it into your Prius really that much more efficient than the electric grid? If so, then prove it.

I already did. Fueleconomy.gov uses the GREET 1.7 model, which is well-to-wheels. It's already figured in. If you don't like it, go argue with the DOE and Argonne National Labs.

"Our carbon footprint shows a car's CO2 emissions in tons per year, along with the CO2 emitted in producing and distributing the fuel."

The bottom line with all of this is that EV proponents have to be honest about their limitations as well as touting their advantages before EVs will be widely adopted. Only telling half the story will result in disgruntled buyers who will spread the word and kill off any potential foothold in the marketplace that EVs may have gained.

[NeilBlanchard]

Right, efficiency and carbon footprint are related but separate issues. And costs and efficiency are related, but separate issues. I am trying to untangle these conflations.

Electric drive vehicles are far more efficient, as end use devices, than are ICE driven vehicles. The fact that gasoline is so "compact" and diesel even more so, *masks* the fact that today's ICE's are pretty dismally inefficient. The largest available battery pack today is worth only about 1.5 gallons of gasoline. This alone forces an EV designer to make better decisions.

And the question of efficiency of the energy chain for electricity is a lot less difficult than it is for oil. I think we need to add in a "cost" for spills and military spending that subsidizes our oil habit; among other things.

So, I think we should use MPGe to compare efficiencies; as the X-Prize has done.

[NeilBlanchard]

[NeilBlanchard]

A hybrid this time (which is a little off topic...):

[NeilBlanchard]

Next episode!

[NeilBlanchard]

New series with a more general focus:

[NeilBlanchard]

[Varn]

Just wondering where all this extra grid power is going to come from. to power electric cars.

About the only new power stations that I have noticed were the big gas turbines which are raising the price of natural gas through the roof and wind energy which around here mainly provides wind energy in the day when the winds are blowing.

How many years ago did california have those rolling brownouts because their grid was over loaded.

I don't see myself driving a "coal" fired auto.