Did anyone decide NOT to go with the twin chargers?

Did anyone decide NOT to go with the twin chargers?

Other than some cost savings, what is your reason? I figure I could just plug in as needed at work since my commute is short. At home I would use 110 volt ac.

gregv64 | 12. februar 2013

Cost savings is the only reason not to get them. It doesn't matter otherwise. The question is whether you think you'll ever use them (i.e. have access to an AC charger with greater than 40amps).

Hills | 12. februar 2013

Cost, broadly defined, is the reason I did not get it, and I don't miss it 9 weeks later. To install twin chargers, it is not just the price you pay Tesla, which is a lot. You need 100 Amp excess to devote to the Model S, rather than 50 Amp for Nema 14-50. Very few people need the charge rate of the twin chargers. Some are willing to pay, for the few times a year they need the fast charge. I have found myself dialing down from 40 Amp majority of the time to start the morning with just charged battery.

110V? that is a different story. 110 is so much slower I doubt most people can put up with it.

If you search this forum, this topic has been discussed extensively on many threads.

Darmok | 12. februar 2013

I didn't get the second charger. The 40A charging rate at home is plenty to charge it overnight, even if the battery is empty (60 kWh). It will be a city car for over 95% of its miles, and any out of town trips will be along the SC system. You're right about cost savings--if the second charger were free I would have taken it, but decided not to pay for something that would rarely, if ever, be used, and probably never actually be needed. If I'm wrong, I'll add it later.

hnashif | 12. februar 2013

Charging 300 kWh battery w/40A takes a little over 9 hours. W/two chargers, and HPWC, this can be reduced to less than 5 hours. The question, how often do you need to recharge a 300 kWh battery in less than 9 hours.

To take advantage of the second charger, you need HPWC and 240v. So you have to factor in the cost of both components and the 240v circuit.

jat | 12. februar 2013

@hnashif - surely you meant 85kWh.

One other thing to consider is a situation like you come home from work and want to head out on a long trip -- halving the time before you can leave may be significant.

I agree it probably isn't worth it unless you get the HPWC as well, since the only high-current J1772 charging stations are in Canada and CHAdeMO (if we get an adapter) will be direct-DC like the superchargers.

@yoelandtina - you might want to reconsider only having 120V charging at home, as it will be pretty much useless, even if you mostly charge at work. You will only get 2-3mi/hr charging.

Objective1 | 12. februar 2013

@hnashif typo:

"Charging 300 kWh battery w/40A takes a little over 9 hours."

Should be: Charging 85 kWh battery w/40A takes a little over 9 hours.


sshrivas | 12. februar 2013

I didn't opt for twin chargers primarily because my single charger will more than handle my daily drive by leaving car charging overnight. Saved a few $$s too.

hnashif | 12. februar 2013

300 mile range not 85kWh. Sorry!

DonS | 12. februar 2013

In the absence of a ubiquitous supercharger network, I thought it prudent to be able to take advantage of the Roadster chargers as well as the rare J1772 charger with 60-80A. If I need another 100 miles to get home or to the next supercharger, a 2 hours wait sounds way better than 4.

Alex K | 12. februar 2013

Twin chargers can be handy if you are on Time of Use (TOU) metering and it would take longer than the TOU interval to charge.

skulleyb | 12. februar 2013

I got both the twin chargers and the HPWC because LADWP is giving 2k rebates.
So I figure that Im ahead on the price of install and the gear. It costs only a little more than install after the rebate.

DouglasR | 12. februar 2013

I didn't configure with twin chargers, and then regretted it. I have since added the second charger. I'l be driving from Seattle to the SF Bay Area later this week, and the second charger means a two-day trip rather than a three-day trip. I expect to make this trip fairly frequently. I do not have an HPWC. NEMA 14-50 is perfectly adequate for home charging.

blc1017 | 12. februar 2013

@DouglasR, we have been considering a trip to Seattle from the SF Bay Area once we get our car. Can you give more information on where the higher amp charging stations are on that route that will allow you to take advantage of your twin chargers? I have done some research but haven't come up with any other than RV sites with 50 amp service.

Laryrob | 12. februar 2013

@douglasR and @blc1017
wouldnt it be great to see some Tesla Superchargers on I-5 from BC to SF? I got the supercharger but not the twin on the expectation the superchargers on the Tesla Map will be installed by year end. take delivery in Bellevue Saturday

DouglasR | 12. februar 2013


Take a look at this map:

Also, ChadS over at TMC has written some great articles on how to do this, with lots of data.

The short answer is, on the way down I plan to charge at Centralia WA (Burgerville), Tigard OR (Tesla showroom), Eugene OR (Sequential Biofuels), and then stay overnight in Canyonville OR (Seven Feathers Casino and Resort). On day two, I plan to charge in Yreka CA (Comfort Inn) and Orland CA (Berry Patch Restaurant), with my destination in Novato, where my brother lives.

nickjhowe | 12. februar 2013

There is an argument that says an HPWC is needed MORE with a 60kWh car (and more still with the 40kWh car) than with an 85. With a 60 and 40 there is a higher likelihood that you'll come home with the car closer to 'empty'. It therefore might be necessary to top off before you go out again on the same day, therefore HPWC.

murraypetera | 12. februar 2013

+nickjhowe - amen.
As is a greater need for DC quick charge. Too bad they are not offering it for the 40.

Jolinar | 12. februar 2013

40kWh battery is not ment for distance travel and road trips, same as LEAF and other pure EVs. Well, at least I understand it that way.

But... is it true that 40kWh could be carged in 2 hours with twin charger? :)

DouglasR | 12. februar 2013


I agree, superchargers along this route will make twin chargers unnecessary for this particular trip. However, I don't know how long it will be until the SC network is filled out up to Vancouver, and even when it is, there are other areas it won't cover. So the twin chargers offer extra flexibility. I wish they had a CHAdeMO adapter as well.

blc1017 | 12. februar 2013


Very helpful! Are you are coming with nothing other than the regular adapters that we are already provided (J1772, NEMA 15-40)? Or, were you able to get a Model S adapter for the Roadster charging stations?

In case you pass a grey Model S going in the oppposite direction as will be us. Can't wait! And if you find you need a charge in Moraga, let us know..we have a 15-40 installed.

DouglasR | 12. februar 2013


I've arranged to borrow a Roadster-to-S adapter. Great community we have here!

If we could get TM to build more of those adapters, I'd bet there would be interest in a bunch of us sharing the cost to get one for each publicly available Roadster HPC -- just padlock the adapter to the HPC.

blc1017 | 12. februar 2013


+1 I couldn't agree more about the need to manufacture more of the adapters.

In the meantime, I'm off to find a friendly Roadster owner in the SF Bay Area with the Model S adapter. | 12. februar 2013

Didn't see a need for twin regrets--NEMA 14-50 does my evening charge in about an hour.

blc1017 | 12. februar 2013


Thanks for the correct term (NEMA 14-50)..I knew that!! Slight dyslexia going on.. | 12. februar 2013

@ blc1017 "15-40" is in the range. One of these nights when it is really cold (I'm in Colorado) I will plug into a standard outlet to see what sort of charge I get overnight.

jat | 12. februar 2013

@murraypetera - the supercharger network is not meant for quick charges in the course of your normal commute, but rather enabling long-distance travel. Look at where the superchargers are -- they are between cities, not in them. SC support isn't offered for the 40kWh battery because they can't get from one to the next, and because they would get far less range in the same time as an 85kWh, making less efficient use of the network.

Superliner | 12. februar 2013

@ KevinR

You should get "some" range off of 110v but the bigger help is that it will keep the battery conditioned "warm" preventing range loss and probably add a few 10's of miles in the process :-)

nickjhowe | 12. februar 2013

@KevinR - someone else (Portia?) reported that on 110V on a cold night the car was reading 'zero' kWh added to the battery.

Brian H | 12. februar 2013

Interesting. Where do you expect to be able to get 80A?

petero | 12. februar 2013

I didn't opt for the twin chargers. Keep in mind how often will you run the battery down to 20% ? In most cases, the Nema 14-50 "tops your tank" in a couple of hours. To me and my use, 'the juice wasn't worth the squeeze.' FYI, I have a 60kWh so my long distance needs are minimal.

On the other hand, you never know what charging developments will develop in the years to come and the extra $1,500 could be important.

DouglasR | 12. februar 2013

@Brian H

All of the places I listed have 70 amp Roadster HPCs (except my brother's house in Novato, CA, where he has a 40 amp J1772). The Tesla showroom in Tigard may also have an 80 amp HPWC, but I'm not sure of that. In Canyonville, they have a 70 amp Roadster charger, but I'll probably use their NEMA 14-50 because I will be charging over night.

If you are asking where in general, rather than where on this trip, then look at the map I linked. All of the blue pins are high amperage stations. In other threads I have posted links to the Sun Country Highway. Most of those are Clipper Creek CS-90 and CS-100 stations, supporting continuous current of 72 and 80 amps, respectively, although I believe most are derated to 70 amps because the Roadster apparently chokes at more than 70 amps from a J1772 connection.

Vic M | 12. februar 2013

I have twin chargers because my vehicle is a sig, but wish I could have saved the money and not had twin charges. I have never been to an AC supply that could use them, and have never had an issue charging over night with the 40A in my garage.

kashiraja | 12. februar 2013

I opted not to get twin charger for reasons already state in this thread and also, it is possible to install it later if you decide you need it anyway.

I did get the super charger, which cannot be installed after the car is manufactured (a Tesla rep told me). I'll be getting 60 kWh battery (would only cost me $8000 for another +25 kHw...though, but it would exceed my budget for this car! :))

brijam | 12. februar 2013

I didn't get the twin charger. While I do have 200 amps running to my home, 40 amps and a NEMA 14-50 is more than enough for my needs. I have a P85.

A 110 connection isn't enough for my usage; 2 miles of charge per hour just won't cut it.

derek | 12. februar 2013

I didn't get dual because I just can't see my use case for it. I'd pretty much never need it. It wasn't a cost issue...I just don't see the need for dual chargers at all.

On 90% of my days I drive under 50 miles (often zero). Don't forget the national average is 35 miles. I'll get all the charge I need within the low overnight rate window using just 40A. Occasionally, I'll dip into the morning higher what.

And, bear in mind that Lithium batteries last longer when they are charged MORE SLOWLY. For this reason, I charge my smartphone with a weak 500mA charger overnight at home...even though Samsung supplies me with a faster 1A charger (which I use when travelling.)

I look at the Tesla the same way I look at my smartphone. I don't want to charge it during the day. I want to count on it lasting through the day, then getting a full charge overnight. A rushed charge seems to me to = stress.

Frankly, I just don't see my model S charging outside of my garage much at all. I'll use the superchargers as they get built out since I've already paid for them and they're fast. But they don't require dual chargers.

And I look at those Leafs pulled up to Chargepoints and I think "This is exactly why I don't have an electric car yet." If I have to try to plug a wire into my car every time I park it, I'm not happy - I'm trying to go to the filling station less, not more! But an EV like the 85Kwh turns my garage into my only gas station. I'll never have to stop for a fill-up again, I'll start every day with a full tank. Having to look for charging locations ruins that.

I have a great laptop with a 7 hour battery. It gives me all I need for an entire day of business travel (airport, airplane, meetings). I see all the punters hunting for wall plugs at the airport or running out of juice in the plane, and think "For $100, you could buy a new battery and not sweat it." Basically, I'll pay for a battery that does 2x the span I normally need it, I'll start every day fresh, and the anxiety fades away.