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I've been doing some research on EV's and wanted to get some data on their efficiencies. I found a fairly good set of tests done at INL here (http://avt.inel.gov/fsev.html). Judging from the "revised" figures from the EPA @ FuelEconomy.gov, these older figures seem more aggressive and may be an applicable comparison to 2007 and earlier EPA FE ratings for gasoline vehicles. These comparisons also assume emissions based on a national average of electricity providers. EV's powered by renewable or carbon neutral sources would have infinite MPG on this comparison.

Car|FE Wh/mi|Eqiv MPG*
1994 BAT International Pickup Trojan (77degF)|436|33.1
1994 Baker EV100 Pickup|435|33.1
1994 Unique Mobility Pickup (77degF)|427|33.8
1994 Dodge Caravan Conversion (77degF)|426|33.8
1999 Chrysler Epic with NiMH|372|38.7
1994 Solectria E-10 (77degF)|364|39.6
1994 BAT International Metro Optima (77degF)|349|41.3
1997 Ford Ranger EV with PbA|337|42.8
1999 Ford Ranger with NiMH|315|45.8
1994 U. S. Electricar Pickup (77degF)|304|47.4
1997 Chevrolet S-10 with PbA|292|49.4
1995 Solectria E-10|283|50.9
1998 Chevrolet S-10 with NiMH|276|52.2
1994 U. S. Electricar Sedan (77degF)|260|55.4
1998 Toyota RAV4 with NiMH|245|58.8
1996 Toyota RAV4 with PbA|235|61.3
1994 BAT International Metro Trojan (77degF)|235|61.3
1999 General Motors EV1 with NiMH |179|80.5
1995 Solectria Force|173|83.3
1997 General Motors EV1 with PbA|164|87.9
1994 Solectria Force (77degF)|145|99.4

*Equivalent MPG assumes 14.4 kWh = 1 gal based on GHG emissions (8.88 oz = 1 kWh = 1.7 lbs GHG)

References: http://avt.inel.gov/fsev.html

Neat stuff. I see that the individual vehicle pdfs list weights (at least on the RAV4 EV page) and that would be an interesting column to add to this table.

DAS

I can follow the DC Wh/mile but the AC charging efficiency data (i.e. RAV4 432Wh-AC mile)? Power Factor Correction, 0.825 does not seem enough to account for this difference.
Separate AC power used for Fan cooling of the battery pack during charge and preheat/precool of car may be the cause but I have a feeling I am missing something.


Thanks for the Table
Good Luck
Andrew

I had thought the battery charging efficiency was a bit better than this but from overall efficiency of 56% and dividing by PCF
=(DC-245Wh/AC-432 Wh/m)/(PCF-0.825) would give 68% as the min battery efficiency.

Probably need the AC Wh/m in your table as this is what you will actually pay and will govern your GHG estimates.
Tesla roadster seems to be have max efficiency of about 70% form their recent blog.

Good Luck
Andrew

WHat Ravev pba beating ravev NIMH? HM...

nice stuff :)

Charger efficiency from the grid is part of the pie...
So is the the cycle efficiency of the batteries...

all good stuff....

related although not the scientific labs results you show...

Mike D's 5th wheel looks like about ~120 Wh / Mile for a EV Insight

Garry G's Full EV Insight looks like depending on speed as low as 103 Wh / Mile ... but probably averages up closer to 120 Wh / mile.

Which looks like a EV Insight would even at 14.4 kWh per gallon would average probably close to 120 MPG ( equivalent ) ... and like it was said... if you have greener or cheaper electricity you favor the EV more.

of course charger from grid to battery efficiency and battery efficiency would also need to balanced in.