

Tesla Model S 60kWh Gets Official EPA Ratings - MikeCapone
http://www.treehugger.com/cars/tesla-model-s-60kwh-gets-official-epa-ratings-95-mpge-208-miles-range.html

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drcube
So the MPG rating is based on the power plant emissions per mile's worth of
energy consumed by the vehicle and comparing that with gasoline emissions?

That's great, but like most consumers I want the MPG based on miles per
dollars. For example, if I can drive 100 miles on ~$3.50 worth of electricity
(or whatever a gallon of gas costs these days), it would be comparable to 100
mpg. Does Tesla or anyone else put out these numbers?

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veemjeem
Wouldn't that be a bit too variable to estimate? If you charge your car during
the day, it would cost a lot more than charging at night. I think in the bay
area, it's around 5 cents per kWh in commercial zones during off-peak hours,
so a full "tank" for the 60kWh battery pack would cost you around $3 -- that's
almost the cost of half a gallon of gas!

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nsxwolf
When everyone starts to buy electric cars, won't we start getting closer to 24
peak hours a day?

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epistasis
Interesting question! Obviously this isn't a problem that's going to happen
any time soon. But if you look at a random day of usage for the California ISO
(actually, the only one I could find) [1], peak load was 30,000 MW and between
midnight and 6AM load was around 22,000 MW. So that's 48,000 MWh, or
48,000,000 KWh, and at 100miles/38KWh, that's 126 million miles of excess
capacity in those hours on the West coast. If the average commute is ~30 miles
round trip, that's 4 million commuters in California, just from current excess
capacity at night time.

Needless to say, it will be a while before Tesla ships 1 million cars in
California, much less 4 million.

[http://www.ferc.gov/market-oversight/mkt-
electric/california...](http://www.ferc.gov/market-oversight/mkt-
electric/california/CAISO-rto-dly-rpt.pdf)

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zefhous
Anyone know the weight difference between the three configurations? Haven't
found it anywhere.

The curb weight of the 85 kWh model is 4,647 lbs, I wonder how much of that is
the battery.

I suspect the weight to be the main difference in efficiency, though each
configuration (as well as the 85 kWh performance version) has different specs
for Peak Motor Power and Peak Motor Torque.

Also, I wonder if power/torque differences between models are because they're
using a different powertrain in each model or if it's an electrical (or
perhaps software) limitation.

I'd love to know if anybody knows more about these things...

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headShrinker
This doesn't really address your questions but it's interesting none the less.
I talked to a rep at a Tesla showroom. Surprisingly, the models seem to all
weigh the same amount. The weight was maintained a specific number so the car
could maintain it's 5 star crash test rating... He speculated that some of the
weight was in the form of actual weights.

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cynwoody
>He speculated that some of the weight was in the form of actual weights.

If true, that would appear to suggest an obvious after-market performance mod.

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stcredzero
_> an obvious after-market performance mod._

With the probable traditionally detrimental effects on ride and handling.

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jlgreco
The "MPGe" thing seems very silly, _particularly_ since if I were using this
car 99% of it's power could be coming from hydro/nuclear/wind. Surely there
must be a better way of comparing efficiency and environmental friendliness.

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timdorr
> if I were using this car 99% of it's power could be coming from
> hydro/nuclear/wind.

Actually, solar, since that's what is powering the free Supercharger network
going up over the next few years: <http://www.teslamotors.com/supercharger>

~~~
jlgreco
Fair enough, though with my usage patterns most of the charging would be done
in my garage. ;)

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angstrom
Which is why they will probably partner with solar city to get people hooked
on solar panels for the home. The convergence of falling costs for solar
panels and falling costs for electric cars with increased range will probably
reach a critical mass similar to the Internet in the 90s and an enormous boost
to the economy from the recaptured opportunity cost being consumed by internal
combustion engines.

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dhughes
Still too expensive and too limited for my taste but I guess someone will buy
it.

In Canada there is such long distances between towns and cities I can't
imagine being limited to 480km ideal would be 1,000km. The deal breaker
(besides the $70,000)is not being able to charge it except at home even at 5
hours with the 20KW charger is still too long.

Plus living in a snowy land where in winter you can see your gas gauge move
you use so much fuel heating the car, spinning wheels, knobby snow tires.

People seem to see vehicles as just another device like a new phone or TV I
don't doubt they'll become more popular and drop in price.

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JshWright
> Still too expensive and too limited for my taste but I guess someone will
> buy it.

> . . . I don't doubt they'll become more popular and drop in price.

That's exactly Telsa's (stated) plan.

Phase 1 was the Roadster. The Roadster was made in small numbers, using very
"hands on" construction methods. It was very expensive, but it was designed to
feel and perform like a very high end vehicle. For people who can drop $150k
on a car (and there are more of those sorts of people than you might think),
the Roadster was a very competitive option

Phase 2 is the Model S. The production line for the Model S is a lot more
automated, and production runs are larger, resulting in a vehicle that is
fairly competitive "mid range" luxury vehicles (e.g. the BMW 6 series).

Phase 3 will be a more "average consumer" targeted vehicle. Taking advantage
of the lessons learned (and to some extent, the capital raised) in the first
two phases.

~~~
dhughes
Nissan is already doing that with the Leaf but it's still too limited I think
only ~120km-160km per full charge. Although I do like the solar panel roof
option to trickle charge the car's batteries.

The ~160km is misleading though because heating the car in winter and in
southern climates cooling the car must require a lot of power.

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richiezc
This is really strange, at the factory test drive last year I spoke with the
head of engineering on the Model S and he said the battery backs for 60 and
85kWh were the same size but with different formulations.

Only the 40kWh was supposed to have a smaller battery pack, in fact if you
upgraded the 40kWh pack you'd need to change the suspension.

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fleitz
Trying to wrap my head around these numbers, I see the rate 35 KWh / 100 miles
which suggests to me you could take a 100 mile drive for about $4.50 (11 cents
per KWh and 15% extra for charging inefficiency)

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ChuckMcM
Yes, so in the more typical 3 gallons of gas car (33.3 mpg) that would set you
back $9-$12 you pay half as much for the energy But electricity, like gas
prices, varies.

A more interesting way to look at it from my perspective is that each 'mile'
has an energy cost of 4.5 cents vs 9 cents. And in a 10,000 mile year that is
$450 not spent.

There are still a lot of unknowns in terms to total cost of ownership, battery
pack replacement, other maintenance.

edit: $450! Just made it in under the wire. Thanks.

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KaeseEs
That's a difference of $450, not $4,500.

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revelation
I don't quite understand. Where do environmental factors come into play with
MPGe? I thought its a plain measure of energy.

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duskwuff
Remember that the "G" in "MPG" stands for "gallons" (of gasoline or diesel
fuel). When your car runs on electricity, the measurement no longer applies
directly, so a conversion is used to treat "gallons" as a proxy for pollution.

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redwood
I don't think it's pollution they're looking at here: it's cost. E.g. the cost
to go the equivalent distance as the cost of a gallon for an otherwise
equivalent car. Perhaps I'm wrong. But bringing emissions in adds significant
value to the electric option: value not yet realized since externalities like
CO2 emissions are not currently paid for.

