TomT said:
Because the EPA only reports what exists at the time of their certification of a vehicle, regardless of the type. They aren't in the crystal ball business. There are simply too many variables.
hill said:
I'm going to GUESS this thought I'm having will fall within the purview of the OP. 73 Mile Range - It dawned on me that with 'expected' range loss over the life of the pack, I wonder WHY didn't EPA plan for that event by putting average numbers into their EPA window stickers. IOW, if owners can expect (for example) to be down at least 20% capacity when they hit mile 'X' ... then why wouldn't EPA flesh out that point. It seems obvious now (what with Arizona owners rightly airing their issues) that "non-new" info would be helpful in owner/buying decisions - but most aren't so forward thinking to try to put an average number on range when you have 3, 4, or 5 years worht of miles on the odometer.
Tom, there's no crystal ball needed. All EPA has to do is add some print on the Monroney along this line:
"All batteries lose capacity as they age. The rate that capacity is lost is affected by a variety of factors, including but not limited to how deeply you discharge your battery between charges, the number of charge cycles, the rate at which you charge, ambient temperature conditions and driving habits. Consult your owner's manual for more details on how to make your battery last longer.
"Vehicle batteries are generally considered at the end of their useful lives when they have lost 20%-30% of their original capacity. When the battery capacity has decreased by 20% (80% of original capacity remaining), the EPA range given above will decrease to 'XX' miles [in this case, 58] under the same conditions. When the battery capacity has decreased by 30% (70% of original capacity remaining), the EPA range given above will fall to 'YY' miles [51 miles in this case]."
Simple, and gives the public the same info that someone with more experience working with storage batteries routinely takes into account when deciding what size battery pack is needed. Or they could just put EPA range at 80%/70% (and maybe 75%) capacity on the sticker, and keep all the fine print in the owner's manual. The important thing is to make the public aware that range when the battery is
new should not be used when calculating whether a BEV has adequate range for your needs.
Personally, I think they shouldn't even put the range while new on the sticker, only the range at the end of life. No one complains if the EPA ratings are too conservative, only if they're too liberal. When they're too conservative they will be pleasantly surprised that they can go further, if not bragging about how much better they're able to do (c.f. threads about 100 mile/200 km Club and this one). I don't recall any threads where anyone brags about how few miles/kWh they get.
Edit: Added a bit.