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.
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).
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.
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.
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.
@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.
"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.
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.
300 mile range not 85kWh. Sorry!
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.
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.
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.
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.
@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.
@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
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.
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.
+nickjhowe - amen.
As is a greater need for DC quick charge. Too bad they are not offering it for the 40.
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? :)
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.
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 you...it 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.
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.
+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.
Didn't see a need for twin chargers...no regrets--NEMA 14-50 does my evening charge in about an hour.
Thanks for the correct term (NEMA 14-50)..I knew that!! Slight dyslexia going on..
@ 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.
@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.
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 :-)
@KevinR - someone else (Portia?) reported that on 110V on a cold night the car was reading 'zero' kWh added to the battery.
Interesting. Where do you expect to be able to get 80A?
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.