On Sep 28, 2015, at 9:12 PM, rayfellow via EV <ev@lists.evdl.org> wrote:

> The difference in per mile costs for an efficient EV vs a
> heavy user is still not all that much.

This is a _very_ significant part of the equation.

My parents recently bought a Leaf. They love it, can't stop talking about it. 
And they literally can't tell the difference in their electric bills since they 
bought it.

In computer programming, it's known as premature optimization. If you have a 
choice of writing code that's quick and easy for the programmer to write and 
later update and maintain, but runs 1000 times slower than some sophisticated 
but difficult-to-understand alternative, which do you write? First, you write 
the quick-and-easy code. And you don't ever look at it again until and unless 
performance is a problem. Even if the easy way is 1000 times slower...if it 
takes ten seconds to execute rather than 0.01 seconds...well, if it's something 
that a single person executes once every four months, why spend hours of 
expensive programmer time saving a low-paid end user half a minute spread out 
over the course of a year? If it's part of the inner event loop of an 
high-performance video game, sure; you squeeze every last CPU cycle out of it. 
But, within rounding, that represents 0% of the computer code written on a 
daily basis.

So it is with electric vehicles. You've got one vehicle that gets ten miles per 
kWh, another that gets "only" three miles per kWh. The one is three times as 
expensive to charge up, so somebody's got to notice, right? Not when the 
difference in cost to drive 30 miles for your commute is 30 miles / (10 - 3 
miles / kWh) * 10¢ / kWh = 43¢ -- not even enough to buy a stamp these days!

Now, consider that a significant fraction of EV owners have rooftop solar, and 
thus their ongoing marginal cost per kWh is literally zero...and why should 
such people even pretend to care about efficiency?

On the list of things that matter in an electric vehicle, efficiency isn't even 
on the list. Indirectly, perhaps, in terms of range and the cost of the battery 
to support the desired range...but make an affordable EV with a 400 mile range 
and efficiency even as bad as an entire kWh / mile, and you won't be able to 
make them fast enough to meet demand.


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