http://www.nhtsa.gov/staticfiles/rulemaking/pdf/cafe/FE-label/FE-label_fact sheet_11242011.PDF
Background http://www.epa.gov/fueleconomy/label/420r10909.pdf
With the various tests/cycles the basic method seems to be; run the car on the dyno THEN recharge it, measuring the electricity drawn from the wall. Obviously this disadvantages electric cars with active cooling systems which will draw additional energy to cool the battery generated by the preceeding test and (depending on the recharging power) the additional heat generated by recharging.
Given that this represents a sort of "road-trip" recharging scenario (though obviously not with a city cycle) does this matter? Well only in the sense that at present, ICE users are used to seeing MPG figures as best case and taking them with a pinch of salt. For EVs, it seems as though the MPGe numbers for some vehicles are not best case.
Draft version here: http://www.smidgeindustriesltd.com/leaf/EPA/EPA_test_procedure_for_EVs-PHEVs-1-13-2011.pdf
Presumably, Tesla will produce something like this: http://www.fiskerautomotive.com/Content/pdf/2012FiskerKarma_EPA_Fuel_Economy_Label.pdf
Background http://www.epa.gov/fueleconomy/label/420r10909.pdf
With the various tests/cycles the basic method seems to be; run the car on the dyno THEN recharge it, measuring the electricity drawn from the wall. Obviously this disadvantages electric cars with active cooling systems which will draw additional energy to cool the battery generated by the preceeding test and (depending on the recharging power) the additional heat generated by recharging.
Given that this represents a sort of "road-trip" recharging scenario (though obviously not with a city cycle) does this matter? Well only in the sense that at present, ICE users are used to seeing MPG figures as best case and taking them with a pinch of salt. For EVs, it seems as though the MPGe numbers for some vehicles are not best case.
Draft version here: http://www.smidgeindustriesltd.com/leaf/EPA/EPA_test_procedure_for_EVs-PHEVs-1-13-2011.pdf
Presumably, Tesla will produce something like this: http://www.fiskerautomotive.com/Content/pdf/2012FiskerKarma_EPA_Fuel_Economy_Label.pdf