Toyota November Tops US Electric Plug In Vehicle Sales For November

That too ...
I was referring to the alternative fuel formulas, which has IIRC a 300% fudge factor adoption encouragement. It is why so many US trucks are flex-fuel -- they get the ethanol bump in CAFE calculated MPG. It is the only way they avoid gas guzzler penalties.

 

I guess you'll have to explain what you meant by "effective cost" in your situation. I am assuming that includes delivery charge and taxes because gasoline price includes all that.

Jeff, I think Volt is probably ideal for you but we'll never know how PiP will do for you. The point I was making is that, Volt can be a total opposite for someone else with different source of electricity. Volt sold outside CARB states are not rated SULEV in tailpipe emission, just ULEV. Bad in tailpipe and upstream.

As you see, the issue with Volt is a nation wide issue. My statements were not directed at anyone specifics and there will be exceptions.

 

USB.. presume you realize that outside of CARB states Toyota Prius is only Bin 3 which is below SULEV level.. (that is Bin 2) in non-carb states the Volt (on ICE) is bin 4, so it is still not quite as clean, but both companies are different in/out of CARB states.

However none of these tailpipe emissions consider the actual ICE usage, they are only measured with the ICE running, so if one is at 63% EV and 33% ICE, the effective emissions are 1/3 of the levels stated.

Upstream gas in Colorado is from tar-sands, the dirtiest type of gas to refine. The Volt at least allows me a choice in upstream by allowing me to buy mostly renewable fuel.

 

Sure, the Volt has a wider range of emissions behavior. I can be better or worse by a significant amount than a Prius or PiP depending on mileage driven and the energy sources used.

I figure my effective rate by comparing equivalent utility bills for the same month from before and after I began charging the car. The change in billing plan to EV rate ends up adding an additional monthly cost that typically works out to 8-12 cents for each kWh I used to charge the car. This is a practical way to calculate it and its much simpler than trying to account for all the margin pricing tiers. In any case, the new EV rate won't have tiers anymore and overnight charging will always be 10 cents.
Maybe some delivery and tax charges apply on top of that but it won't make a big difference and some of those would be added on even if I wasn't charging the car.

As for the PiP, it wouldn't be as effective for me. I can sketch that out briefly in a separate post. In any case, I wanted to try something a little different after driving only Prius models for 10 years.

 

MPGe is only idiocy when it isn't used as intended. Which is as a conversion of KWh/100 miles into a format the public prefers and is comfortable with. It can also be used for diesel, CNG, LPG, and hydrogen. Some of those are presented as MPGe on the sticker now.

It could be problematic with energy carriers like electricity. MPG could be a problem if it had to consider the upstream differences of the differing crudes, tar sands, etc. But it is only presenting the efficiency of the vehicle. Like MPG only considers gasoline from the pump, MPGe only considers electricity from the wall, or pump as the case may.

For your question about the plug in and coal powered electric, it would be MPGe. Being an energy carrier, it doesn't matter what made the electricity to the car. Whether coal, gas, wind, solar, hydro, or nuclear made the eletricity, the car's efficiency for getting down the road won't change. The power company buying more wind doesn't change the kWh your home used.

I realized the error in your Rav4 EV and Long Ranger math. You forgot the efficiency of the generator.

 

I asked about OIL powered electric.

I set the EV drivetrain efficiency at 80%

 

You still think the MPGe of the Rav4 plus trailer is 78.6 even though you say it goes 27 miles while consuming 1 gallon of gas?

The definition of MPGe being used by EPA is:

(Total miles) x (energy in a gallon of gas) / (total energy consumed)

Miles per gallon gasoline equivalent - Wikipedia, the free encyclopedia

In other words:

27 MPGe = (27 x 33.7 kWh) / 33.7 kWh

In other words, by definition, if you are ignoring the Rav4 battery and all your energy comes from consuming gasoline then MPGe is the same thing as MPG.

The plugin hybrid MPGe values are near 60 because they are mixing in the energy in the fully grid charged battery pack using a utility factor based on typical driving distance patterns.

 

I sure do. Ergo, the stupidity of MPG(e).

Moreover, the MPG(e) of the RAV+trailer does not change regardless of of the generator efficiency. It could take a HUNDRED gallons of petrol to send ~ 11 kwh of electricity to the RAV that then travels 27 miles. The MPG(e) calc only relies on the wh/mile energy consumption of the vehicle, estimated in my earlier post at about 400 wh/mile. It remains about 78 MPG(e).

 

You're doing it wrong.

 

I don't think so.

The RAV(ev)consumes about 400 wh/mile while towing it's own little fossil fuel generator.
Using 33.4 kwh/gallon as the energy equivalent for petrol,
33.4/.4 = 83.5 MPG(e).

My earlier post had a (hopefully more accurate) wh/mile for the car, thus the slightly lower MPG(e) results.

 

Jeff,

I think Sagebrush wants to talk about the MPGe of the Rav(ev) and everyone else is talking about the combined MPGe of the Rav(ev) with the range extender(ice). Some things get lost in translation.

It's a bit like comparing the PiP's EV mode vs HV mode.

 

As best I can tell from his ultra dry sense of humor, he's trying to make the point that he thinks MPGe is a poor metric because it ignores the original source and generating efficiency of the grid power used to charge the battery.

Of course, this is unknowable to the folks creating a car's Monroney sticker while they do know the efficiency of the builtin gas engine (or EV trailer engine). So, he's removing engine/generation efficiency from the gasoline side of the equation as well. And mumbo-jumbo-presto-chango, the end result of his calculational gymnastics is that the gas engine MPGe (78) is essentially the same as the battery-only MPGe (74).

I'm not very fond of MPGe either. I think it confuses people way more than it helps. I think they should have just kept expressing EV efficiency as kWh per 100 miles and separately displayed the gas engine efficiency as both MPG (for historical reasons) and gallons per 100 miles.

 

My bad about the coal and oil mix up, but that doesn't change my answer. MPGe, as used by the EPA on the window stick, is just for comparing the vehicle efficiency. Since the efficiencies of electric generation and petroleum refining vary, that sticker number ignores them. Has it has done since first implemented.

You need to clarify this:

27.5% is the ICE converting gasoline's chemical energy into kinetic.
The EV 80% is converting electric into kinetic, and the losses of the drive train.​

Where is the accounting of the losses of converting the ICE kinetic into the EV electric?

No, he's talking about the trailer combo, and trying to say that if we ignore the efficiencies of electric generation at the plant, we should ignore them for a generator being towed by the EV.

In which case, he is incorrectly using MPGe for the purpose vehicle efficiency. If he were, hybrids, even non plug ins, would list a MPGe, instead of MPG, number base on the ratio use of motor(electric) and engine(gasoline) during the test.

​

It's a poor metric for well to wheels, but so is MPG. Upstream costs were never the target of vehicle emission regulations which gave us the fuel economy sticker, though.
Energy source per 100 miles would have been better all around, but confused people in a focus group chose MPGe(in the Wiki article).
MPGe does provide for more direct comparisons of other alternate fuels, like CNG and diesel that always like to bring up its energy density advantage.​

 

Heh, I have been accused of this before, but I'm trying to be serious here.

Exactly.

The efficiency of the petrol engine to a very large degree determines the MPG. MPG(e) ignores that efficiency *completely*, even though it is present for all electricity made from fossil fuels. So long as all the cars are using petrol, it is reasonable then to only talk about car MPG. It is not reasonable to talk about MPG or MPG(e) when different fuels (let along carriers) power the cars.

, yes, so long as the petrol engine is exterior to the EV and therefore ignored.

Consider this situation: I buy a RAV EV rated 74 MPG(e). Then I buy the cheapest generator I can find, that runs at about 15% efficiency, and use it to fill up storage batteries in my home (being green and off-grid.) I plug in (how COOL) my RAV EV at home and fill the car up with genuine, to good to be true, clean electricity, incurring about 30% losses along the way.

Calculated out, a gallon of petrol poured into the generator netted me (based on 400 wh/mile) about 8.74 miles. But guess what ? I am delighted, because my 'lectric car gets (tada) 74 MPG(e).

I am not misconstruing the calc; I am pointing out why it is ludicrous. More to the point, I am pointing out that MPG(petrol) cannot be compared to MPG(electric) in any meaningful way.

 

EPA MPGe is the vehicle efficiency. It does not include fuel production (upstream). For an EV, the efficiency is from wall-to-wheel. For gas, it is from tank-to-wheel.

The problem with towing a generator with an EV is, do you consider it on-board or not?

If we don't consider it on-board, then RAV4 EV is rated 78 MPGe (pre-2008 rating) on electricity. We ignore the gas generator inefficiency like we do with the power plants.

If we consider it as on-board, then it will be around 27 MPG (as Darell report). A gallon of gas would go as far as a regular gas RAV4, 27 miles.

Today's MPGe rating takes out 30% to account for higher speed, A/C, heating, etc, so 78 MPGe would really be 55 MPGe today.

 

I think 400 wh/mi is low. RAV4 EV is rated 430 Wh/mi and that's pre-2008 rating. If it tows the gas generator, it'll be even higher.

If we were to calculate backward from Darell's 27 MPG:

33,700 Wh / 27 miles = 1,248 Wh/mi

The gas generator efficiency has to be ~35% to get 437 Wh/mi. If gas generator efficiency is 30%, it is 404 Wh/mi. Perhaps he drove in lighter condition than the old EPA cycle.

 

You may well be right, but the basic argument is unchanged: MPG(petrol) cannot be compared to MPG(electric) in any useful way.

I think it was drivinnation who posted that a 60 MPG(e) Volt is "better" than a 50 MPG Prius. It is that kind of misunderstanding I want our community rid of.

 

As Trollbait points out, we still need MPGe for fossil fuel engines running on CNG etc. it does make sense to compare a gasoline engine against a CNG engine. This is why it makes more sense to consider MPG = MPGe for a gasoline engine and MPGe for a CNG engine along with a suitable energy conversion calculation into the gasoline equivalent value that most people already understand.

So, MPGe for the gas-only aspect of a mythical RAV4 PHEV would be 27, and the mythical CNG variant would be a roughly similar number although the actual engine design and efficiency might be slightly different. To avoid confusion, MPGe shouldn't be used to characterize the grid-charged battery efficiency of the vehicle.

 

This would be a practical and reasonable approach.

 

MPGe is used for hydrogen combustion or fuel cell vehicles also.