MSimon wrote:
A production car is not going to spend the money required to get the weight reductions and motor performance Tesla did. And that number might represent out of the door designed number. i.e. not counting 30% reserve for battery life, reserve for battery aging, reserve for production tolerances etc.
Tesla may not need all those reserves or can shave them by being basically hand built.
But I do agree hybrids are the way to go for at least 10 to 20 years. Shake down the electrics and introduce them gradually.
My guess is that we will still be using liquid fuels in very large volumes 100 years from now.
The GM Volt at 1600kg curb wt is getting around 40 miles out of 8 Kwh, or 5 miles /kwh. Granted it's not in production yet, but the numbers will be reasonably close that.
The Tesla is a targeted as a high performance sports car, some efficiency trade offs were certainly made to achieve that high performance.
In any case the batteries are such a dominant cost of the vehicle that optimizing system efficiency has a high return on cost. Increasing system efficiency reduces battery cost (by reducing battery size) so much you can spend a considerable amount of money and effort in that direction. In other words it's very cost effective to spend money on being very efficient. This should be true of any vehicle designs in this class.
btw the Volt battery is 16Kwh, but it's derated to only 8kwh. The recharge cycle life is extended by never fully charging the battery nor fully discharging it. Full charge is something like 80% capacity, discharged is at 30%.
I agree, the advantages of liquid fuel are just enormous. We take it for granted but gasoline is really magic stuff with it's huge energy capacity, ease of handling, storage, and transportation. With serial hybrids like the Volt you can also optimize the generator engine because you can run it at constant load/constant rpm and thermodynamic efficiency can be in the 35%-40% range.
I agree completely, liquid fuels are going to be around for a very long time.