Charging a Tesla roadster from household outlet could take 30 hours!
The gang from Tesla left their Silicon Valley home base to pay a visit to the vicinity of the Big Apple this week. Part of the purpose of the trip was to spend some time with some of the people in the area who've plunked down cash toward a Roadster but haven't yet taken delivery (which would be almost everyone on the customer list at this point). One interesting note in the article from Greenwich Time is the length of time required to charge up the Roadster's battery. They note that charging the battery from a normal household outlet could take up to 30 hours. The Roadster's battery has a capacity of 53kWh. Tesla quotes a charge time of 3-3.5, but that is based on charging from a 220V 80A circuit. If, on the other hand, you plug the car into a typical outlet in your living room, you would only have 15A flowing at 110V. That's 53,000W / (110V * 15) = 32.12 hours. So if you plan to get yourself a plug-in electric car with any kind of serious range, be prepared to have an electrician install a high current outlet to charge it. At the very least you'll want a 220V/40A circuit for overnight charging in 6-7 hours.
[Source: Greenwich Time]
Reader Comments (Page 2 of 2)
Justin 12:46PM (7/07/2008)
I got cut off by those guys in NYC when I was just down there. I thought it was more than funny to see the Tesla on the road. Well at least this means I wasnt hallucinating from being in the car for 19 hours.....
So onto the charging issue. If Tesla gives us a charger and we get it installed your only looking to pay for the cost of installation. Not much at all, couple hundred bucks and maybe a case of beer, especially when you compair it to the cost of the car.. Worried about overloading or taking power away from other things.... Dont, you can probably charge your Tesla, surf ABG, and watch the game all at once from the comfort of your mansion. Or just plug it in at your guest house, and problem solved! Because isnt that what all Tesla owners are going to be doing anyway?
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Sam Abuelsamid 9:37AM (7/07/2008)
The point of this post if you actually read through the whole paragraph was to point out that charging any EV, not just a Tesla is dependent on the circuit you plug it in to. It doesn't matter if you have a battery capable of quick charges if you have a slow feed. If you expect to charge the battery quickly, you need a high-voltage, high-current outlet.
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virgil 10:52AM (7/07/2008)
The bigger worry here is the cost....
53kwh at 10c/kwh is more than $5 for a charge. If you're paying the utility company's mark-up for wind power, plus taxes, it's closer to $7/charge. Certainly not a lot if you're dropping $100k on a car, but also not just pocket change if you have a 100 mile/day round-trip commute (as many in LA do).
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GoodCheer 3:01PM (7/07/2008)
If you're only going 100 miles (round trip), then you're not using the whole 53 kWh.
The EPA range of the Roadster is 221 miles, so 100 miles would use about 24 kWh, so at $0.12/kWh that commute costs you less than $3. Less than a gallon of gas.
Mark 7:13PM (7/09/2008)
A full recharge of the Roadster ESS actually requires 70kWh of
electricity; 25% of the energy runs the battery cooler and gets
dumped as heat by the charger electronics while 75% goes into the ESS. http://en.wikipedia.org/wiki/Tesla_Roadster#Petroleum-Equivalent_Efficiency
PG&E's night time E-9 rate for EV owners is only 5.5¢ per kWh.
http://www.pge.com/mybusiness/environment/pge/cleanair/electricdrivevehicles/charging/index.shtml
rj 12:54PM (7/07/2008)
The cost of electricity is nothing compared to the cost of the battery.
The tesla uses about 6800 lithium ion cells, and based on the the pack voltage and the rated capacity we can estimate that each cell has a capacity around 2100 to 2200 mAh
Let us assume that each cell costs $5 - $10
A replacement laptop battery runs $100 and may have 16 cells (6.25 per cell) so this seems reasonable.
what is 6800* $5 ?
$34,000 for a battery pack.
If we assume the pack will last 5 yrs.
If we assume 40 miles each day 5 days a week for 5 yr that is 52,000 miles
$34,000 / 52,000 miles = $0.65 per mile in battery cost
Ignoring the cost of electricity that is like getting
6 mpg
$4 per gal / 6 mpg = $0.66 / per mile
If you are spending $100k on a sports car fuel economy can't be too much of a concern.
http://www.teslamotors.com/display_data/TeslaRoadsterBatterySystem.pdf
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jake 3:21PM (7/07/2008)
I don't think it's quite fair to use the battery pack cost as an mpg equivalent, after all, it's a sports car and $100k isn't far off for a 0-60 in under 4 seconds sports car.
I think the fuel economy is still of SOME concern here b/c a lot of people buying this car wants at least very high plug-to-wheel efficiency. Yes it's a sports car, but a large part of the market for this car still wants that green image.
Mark 2:14PM (7/09/2008)
Tesla estimates the pack will last 5 years or 100k miles before capacity drops to 80% of new. They estimate replacement will cost $12000 in 2013 (discounting for inflation makes that only $10750 in 2008 dollars).
Mark 6:14PM (7/29/2008)
Has anyone published a TCO (Total Cost of Ownership) analysis for the Tesla Roadster? Edmunds.com has TCO's for lots of other cars (depreciation, insurance, loan interest, fuel, maintenance, etc...), but not yet for the Roadster.
mndasher 3:16PM (7/13/2009)
The Tesla article says the car uses 6800 type 18650 Li-ion batteries At today's prices they are nearly $10.00 each. http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=4869
I suppose if you buy 6800 of them you will get a quantity discount. But yikes.
rotej 2:25PM (7/09/2008)
test
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rotej 2:27PM (7/09/2008)
test2
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rotej 2:34PM (7/09/2008)
This is cool stuff
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James 11:56AM (7/10/2008)
Don't forget that you can only charge continuously at 80% of the rating of the circuit by National Electric Code.
15Ax80%=12A.
53,000Wh / 12A / 115V / 75% Efficiency = 51h for full charge on standard outlet.
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BlackbirdHighway 10:58AM (7/11/2008)
Yeah, Edmonds.com doesn't have the Tesla, but the TCO on the Porsche 911 Turbo Convertible is $168,554, or $2.25 per mile.
I'm sure the Tesla isn't any worse than that, probably a bit better.
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cs 6:42PM (10/21/2008)
litium battery will last 100,000 miles. assuming tesla doesn't get a discount for buying 6872 cells, that's $43,000 ($6.25/cell). that's today's cost for being at the edge of a new technology. a simpler battery and ultracapacitors will cost a fraction of that in a few years. tesla will have a cheaper battery by the time someone needs a new one.
100,000 mile / 250 mile/charge = 400 chargings. 400 * 53 kWh * $0.06/kWh / 75% = $1696 (over 100k). while comparing a maintenance cost with fueling cost is faulty logic, it works out to $0.45/mile. at $4/gal, that's equivalent to 9 mpg mpg.
don't forget supercars in that range have thousand dollar oil changes, reliability issues, and massive repair costs. the tesla is virtually maintenance free...so cost of ownership is still lower.
electricity is expensive in your area! cost in canada is $0.06/kWh during the day...less at night (when you'd be recharging). $5000 worth of solar panels will let you sell electricity back to the grid at daytime cost, and charge at nighttime cost. free energy:)
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mndasher 3:06PM (7/13/2009)
Charging at 240 v and 40 A for a Tesla is putting 9600 watts in to the charging circuits, and the battery. A lot of heat will be generated. 100 percent of the heat is wasted energy. Unless you use it to heat your garage. If it is summer time, and the garage is closed I would expect it to get a lot warmer in there.
Power plants do not operate at much more than 35-40 percent efficiency. Nuclear plants are about 25 percent (for safety reasons).
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