Let's be fair on the high-mileage EVs

[aerohead]

Originally Posted by theunchosen

I still don't get where people are coming off saying EV is so in efficient.

How many different ways do I have to lay out the numbers?

EV rapes gas. . .in all aspecs except for power density(its hard to compete batteries to fuel 6 pounds to several hundred)

theunchosen,hang on! One of a certain very large car companies' legal eagles once said that Americans had to be pushed to the "brink" before they would act.I think we're close.There's a great deal of consensus on big issues now that didn't exist ten years ago.With Lithium Ion technology(we have a lot of lithium) and renewable energy streaming on line,and especially in light of the global economic situation,and environmental concerns,I feel like we're close to that tipping point.I think plug-in EV will be a household word before long.

[theunchosen]

Well. . .it will be kind of meaningless to have that many plug-in hybrids.
Unless regulations on nuclear power are lifted, there will be massive power outages.

Part of the enormous cost of nuclear power is having it inspected fifty times before you do any construction and a twenty more times per year.

I'm ok with the project being checked by someone from the outside(just in case someone makes a mistake) but the enormous up front cost and time for the inspections keeps nuclear from being a viable option. Overseas most companies that try to go nuclear go belly up because the inspections take them over project deadlines and they are not able to meet contracts or start paying off the loans they took to build the plant.

[NachtRitter]

Seems this thread has gone a bit OT...

I had originally interpreted the OP point to be something to the effect of: There should be a consistent method of determining FE for both electric and ICE vehicles. Put x amount of energy in, and get y amount of 'work' (measured by distance driven) out. Missed the part about assuming that the gasoline had to be converted to electricity so should knock off 50%. I don't think that makes any sense.

The WTW discussion is interesting, but does not / cannot address the question of mpg equivelance adequately. Once the gasoline is in my tank, the mpg value doesn't change as a result of the efficiency of the refinement process. But that is what mpg measures. Nor do the electrons in the battery cause the EV to go further if they were generated by wind versus by coal or gasoline. There is simply too much variance in the 'WTP' (well to pump, or 'well' to plug) to come up with a dependable number.

Not sure why it can't be as simple as agreeing on an energy equivalent between electricity and gasoline, and then measuring how much goes into the "tank". The charger connection is the measurement interface (just as the fuel pump is for the ICE) between two "black boxes"... doesn't matter (for the purposes of MPG measurement) what happened to create the energy before, nor how exactly the energy is converted to forward motion after. Agree on where the measurement takes place for EVs... before or after the charger. There, done.

I've always felt that EVs are better overall (when considering WTW), but trying to incorporate that point into an mpg equivelant measurement (which is not WTW to begin with) just won't work.

[trebuchet03]

Originally Posted by NachtRitter

The WTW discussion is interesting, but does not / cannot address the question of mpg equivelance adequately. Once the gasoline is in my tank, the mpg value doesn't change as a result of the efficiency of the refinement process. But that is what mpg measures. Nor do the electrons in the battery cause the EV to go further if they were generated by wind versus by coal or gasoline. There is simply too much variance in the 'WTP' (well to pump, or 'well' to plug) to come up with a dependable number.

I completely agree....

I think the complaint from the OP is rooted in that mpg is a poor metric for comparison. Potentially, but that all depends on the information one is trying to convey. MPG is understood by a VERY large group of non-experts - the most important group. If everyone could tell the difference between the Brayton and Rankine cycle, we probably would never be expressing units in MPG to begin with


Off topic, but there's been quite a few wild assumptions in this thread.... For one, the assumption of 100% coal power... I see the locations of many members, and they're not all in one place. As the grid is one large connected system, power generation efficiency should be the composite efficiency of all power sources weighted by dependence.

I live near a natural gas fired plant that allegedly uses an ultra critical turbine design - that sort of plant can get damn near 50% efficient with reheat phases and proper cooling towers (it has the stereotypical "nuclear" natural draft design - everyone thinks it's nuclear, it's not). For me to get that sort of well to wheel efficiency while someone else gets something different would be unfair


EIA - Electricity Data, Electric Power Capacity and Fuel Use, Electric Surveys and Analysis

Someone else can finish that analysis I feel it would be interesting, but fruitless as it conveys an apparently mystic number understood only by experts.

[dcb]

Originally Posted by NachtRitter

...Not sure why it can't be as simple as agreeing on an energy equivalent between electricity and gasoline...

LOL, even that is not simple

From the wiki discussions on gasoline:
BTU per gallon of gasoline

• 1 kilowatt hour = 3,412.14163 BTU

But nobody seems to know how much energy is supposed to be in a gallon of gas.

• 1 Gallon = 124,000 Btu (rounded to nearest 1000)(based on U.S. consumption, 2007)DOE
• 1 Gallon = 115,000 Btu ORNL
• 1 Gallon = 114,100 Btu About.com
• 1 Gallon = 114,063 Btu NAFA.org
• 1 Gallon = 114,000 Btu EPA
• 1 Gallon = 110,400 Btu/gallon in California [www.vta.org/bart/documents/final_eir/vl_1_ch_4_08_energy.pdf VTA]

• 1 Gallon = 114,000 Btu/gallon according to NIST. They came up with the GGE concept in 1994.NIST

I will assume NIST's figure for 114,000 Btu per gallon of base gasoline is their standard, since they are the ones behind the GGE concept. EPA's figure agrees with this in most places. Kgrr (talk) 16:02, 1 January 2009 (UTC)
Even some government institutions cannot be internally consistent:

• 1 Gallon = 115,400 Btu/gallon ORNL

This figure seems to gain a lot of traction:

• 1 Gallon = 114,264 Btu/gallon AFDC
• 1 Gallon = 114,264 Btu/gallon Province of Alberta, Canada
• 1 Gallon = 114,264 Btu/gallon Chemistry course

[NachtRitter]

dcb,

Ha ha... Wow!

Nevertheless, it seems like in the tiny slice of the world represented by this forum, it should be possible to agree on one of those conversion standards so that the EV comparison in mpg numbers are at least consistent with each other. Either the forum moderators can "dictate" the conversion to be used, or they could put it up for a vote. The way the current fuel log works, using the agreed-upon conversion would be voluntary, or the fuel log could be modified (says the guy in the peanut gallery) to accomodate electric vehicles with a field for KWh consumed instead of gallons (with the conversion to mpg being done in the code). Or even forget about the conversion, and just record and display the miles/KWh (though I definitely agree with Trebuchet that the fuel-based measure of mpg or L/100km is something the vast majority of folks can grasp).

It is in that sense that I meant "simple"; no need to figure out (or fight about) the correct WTW factor that needs to be applied.

I don't think it really matters which conversion is used for BTU in order to determine the KWh equivelant... after all, gasoline, diesel, and ethanol each have significantly different BTU equivelants yet we still use the same mpg measure for each one. Consistency is really more important.

[bennelson]

Yipes! What a thread!

In the upper-left corner of the Ecomodder home page, there is a listing of the top 10 most efficient vehicles on Ecomodder.

The ranking is in Miles-Per-Gallon. That's what our culture expects to hear when they want to know economy of a vehicle.

I use "Miles Per Gallon equivalent" when talking with the general public because people GET MPG. If I am talking with an electric vehicle person, I will speak of watt-hours-per-mile. They will get that.

Electric and gasoline ARE apples to oranges! It is a bit difficult to compare the two.

Electric vehicles are a bit like democracy - the worst thing out there except for everything else!

Perhaps we need a listing of vehicle economy where it is listed in watt-hours-per-mile - then just make all gasoline vehicles convert to that!

[Coyote X]

Just to be annoying to everyone, what about other sources of making a car go?

natural gas, propane, diesel, etc? The energy output/creation cost of diesel is different than gasoline so should there be a conversion for a gallon of gas to a gallon of diesel? The other two are gasses so a gallon by volume doesn't mean much without pressure and temperature. Also the same issues as electric are present with the gasses in how you compare to gasoline.

None of them are similar so to get a comparison to compare one to the other is not easy. There are so many ways to measure them. Well to tires natural gas locally here would win since it is just coming straight out of the ground and ran to the houses and a small pump that doesn't take that much power to build pressure slowly and refill the tank. So there is no transmission loss of any sort on natural gas here it would be just the bit of power used for the pump and the engine efficiency.

Pretty much any measurement is going to be arbitrary and can be argued either way so I just say admit it is an arbitrary decision and just explain it as best as possible. I would rather have the top 10 split up into categories just for the people who want to see how good they are doing in relation to similar vehicles(be good for categories and searches). But an overall top 10 is always going be biased and give an advantage to one type of car over the others. I would also say double the pollution output of the coal plant. You guys have no idea how much pollution the mines generate to mine coal. Imagine 50 large rock truck tires dumped in a hole and burned. That is typical for tire disposal

For my car I am not sure if I am even going to bother with measuring electric usage regularly. My electric bill is always the minimum amount and charging the car isn't going to change it so to me it is basically free

[dcb]

I did want to come back to cost for a bit.

Average US cost for gasoline in 2007 in terms of KWH ~ $0.25/kWh (I know, I know)

Average US cost for electricity in 2007 $0.09/kWh

People may not understand WTW and mpge, but everyone understands cost.

Yes, have standard conversion built in and applied to the whole garage. Diesels should probably have a correction factor too by that logic.

[NachtRitter]

Hmmm... maybe the right measure should be cost per mile... except then it would be argued what the baseline monetary system should be used...

BTW - I understand there is a revamp of the top 10 list in the works, according to http://ecomodder.com/forum/showthread.php/garage-over-epa-question-7580.html.