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Twin Charger vs. Single Charger Configuration

Trying to decide whether to order the Twin Chargers. Don't really need it for daily use but I gather it cuts the time for super charging in half.

Does anyone know if the Twin Configuration adds weight to the car. If so, how much?

Super chargers do not use the internal chargers... so no difference here.
The only difference is using an AC source... at home or on the road you need > 40 A AC source to take advantage of the twin charger option.

It cuts home charging time in half, which helps if you need a mid day refill (I use that a lot).

No effect at Supercharger.

Adds 10-20 pounds of mass (guesstimate).

Like Kleist said, single or twin chargers has nothing to do with Tesla Supercharger which uses DC, it has to do with AC.

Now, for AC, when you don’t have access to Tesla Supercharger stations:

If you use your car just as if it is a Nissan Leaf that you would never go long distance, then you might not need a twin charger.

If you are at home, you don’t mind sleep 10 hours waiting for the single charger to charge your car.

While you are on the road, you may not have a luxury to sleep that much.

I was told when I asked about this at the Chicago show room that while the second charger can be installed after you take delivery it would be more expensive.

I was advised that if I planed to take road trips to get the second charger even if I did not get the HPWC because more and more Level 3 public charging stations are going online and those would require the dual chargers to get the increased charging speed.

I have not yet ordered mine but based on this advice I am considering it as the cost to get it install at build is significantly less then after delivery because you do not need to pay for labor to install it.

If you don't have a High Power Wall Charger the twin chargers are useless. In addition, the supercharging stations do not use the on-board chargers. The twin chargers might be useful if you found an 80amp circuit to plug into, but I don't know of any public stations that provide that.

I hope that helps.

There are 80 amperes around but it's hard to find out which:

Thanks for the clarifications. Very helpful. I am thinking if I have my home wired for 240/80 amp, I can use the Twin on board w/o springing for the fancy charging station in my garage.

Does that make sense?

vicelike currently there is no way to have the car draw more then 50amps without a HPWC from home unless you get an after marker level 3 charging station


Let me see if I got this right.

Since I can comfortably live with a 31 mile per hour rate of charge which I can get from a 240/40 configuration and road trip recharge rates from the Super Charger stations are unrelated to whether or not I have a twin configuration on board, there is no good reason to go for the Twin or the Fancy charging station extras, given how I expect to use the car.

Thanks for the advice people.

@ Vicelike, keep in mind that without twin chargers on board, you will not be able to take advantage of higher capacity J1772 chargers that are currently being installed in some portions of the US. These chargers can supposedly go up to 100A, but without twin chargers you will not be able to exceed 40/50A. Only time will tell how pervasive these new J1772 chargers will be.

Following-up on that last post, I also don't believe that Tesla has any adapters that would work on the J1772 "combo" plug that would be required for this type of charging station. It's affectionately referred to as a "frankenplug" online :)

For the price of the second charger in relation to the entire car I can't imagine not having it installed. My wife and I sometimes head to Yorkdale where there is a Tesla store, and hence an 80A charger. We've charged the car from nearly empty to full over lunch and a short shopping session. It's very convenient to have dual chargers!


You got it right BASED on your past history. There’s a saying:

"Past Performance is Not Necessarily Indicative of Future Results"

Which might be applicable to your case.

Owners after owners have been reported of their change in driving habit. They suddenly got a “Tesla grin”. They suddenly drive much much more than they used to.

After you finalized with your single charger, pray that you won’t get bit by Tesla bug!

Don’t worry, if you do, just pay a little more in money and installation time for the cure :)

Excellent point, Jewsh


You asked a similar question in another thread, but here is the answer I gave there:

The second charger is $3,600 plus tax, installed, when you add it after delivery. I believe it is $1,500 when you order it with the car. Hademarco is not correct. There are lots of 70+ amp public stations that make road trips much easier with the twin chargers, depending on where you live. You can find them from Vancouver, B.C. down to San Diego on the west coast (, and from Vancouver to Nova Scotia across the southern tier of Canada ( There are also a handful scattered elsewhere around the country.

@jrkbob1975 and AmpedRealtor are wrong: there are plenty of public stations that deliver power at 70+ amps, and for the J1772 stations (e.g., Clipper Creek CS-90), you do not need anything other than the J1772 adapter that comes with your car. For the Roadster stations, you do need a special adapter, but you can buy or borrow one. Whether you will use these high amp stations depends a lot on where you live and where you intend to drive. I drove from Seattle down to the SF Bay Area, and the trip would have been much more difficult without the twin chargers.

One other point: you will NOT get 31 rated miles per hour of charge with your 240/40 configuration. Count on around 24-29. That is because, first, the 31 mph rate advertised is based on "ideal" miles, and is not very realistic; rated miles will be lower. Second, your home outlet will not likely maintain the full 240/40 current throughout the charge.

In short, if you think the Superchargers can be used for EVERYWHERE you want to drive, and if you are happy with 24-29 mph charge rate at home, then don't get the twin chargers.

If you live or drive near high amperage stations (west coast, southern Canada), or want to drive places without superchargers, but with high amp stations, or want to take advantage of future installation of high amp stations, or want faster charging at home, then get the twin chargers. Also get them if $1,500 doesn't mean that much to you.

One EE ("Peter7") even rigged up his own Multi-Input EVSE so he could use 2 14-50s at once at RV parks.

Singel chargers will charge up to 10kw, so if you come across that can provide you with 12kw or 16,5kw your car can only charge with 10kw. If your car have twin chargers you can get use of power between 10kw-20kw.

There are standard J1772 plugs on many charging stations. Not just the "frankenplug" that is currently in development to accommodate true "level 3" charging. "Level 2" charging is actually a large range of voltage/amperage combinations.

I have used the standard j1772 plug on a charging station in San Luis Obispo to charge at 240V AC and 70Amps. That's basically the same as a high-powered wall connector.

So, for road trips where there are no superchargers, you may come across a particularly good J1772 charger that will give you quick juice.

However, most of the J1772 chargers out there are the minimum required to call it "Level 2:" 30 Amps, 240V. That is the same as my old dryer plug in my garage. There is no incentive for these electric charging networks to put in the better "Level 2" stations, since they charge you by the hour. Most electric cars can't even take advantage of the higher charging rates. So, they spend extra money to accommodate only a small number of people, who charge quicker and use more electricity in less time and pay them less total.

I would say, get the twin charger if you ever plan on going on a road trip, or if you ever plan on putting the HPWC in your house. Bear in mind, like someone here said, you'll get bitten by the Tesla bug. It's so much fun to drive, that you'll want to drive it everywhere and in all situations.

I would jut get it. And I did.

Money would be better spent elsewhere

@ DouglasR, thanks for the correction. I did not know that the standard J1772 connection could go up to 70A. That is great news! I'm assuming any higher (i.e., 100A) would require the new combo connector. So clearly there is an advantage to getting the twin chargers if you encounter a 70A charging station in the wild. Also, the Tesla Store here in Scottsdale has two Roadster chargers in the parking lot that are free to use. Are those going to be more than 40A?

If you plan to charge on the go, having twin chargers is a must. Super chargers will never be everywhere. Level 2 chargers currently go up to 100 amps. More and more of the J1772 chargers put out 70 to 90 amps and they are becoming the norm in Canada. There are also a lot of roadster HP chargers available that put out 70 amps (you need an adapter to tap into those). Spend the $1500 now and save the extra cost of the upgrade later when you realize you have better things to do with your time.

I also suspect that when it comes time for resale, this will be a question asked by prospective buyers. Remember, if Tesla, Nissan and others are successful we are going to see higher amperage chargers pop up like weeds. If that happens, a few years from now you may regret not having the twin chargers in a resale situation when that may be a desirable feature to have.


I agree with you that there is little incentive to upgrade most existing commercial public charge stations to 70+ amps. However, when new stations are installed, the cost difference is not that great. And while many commercial networks are paid by the hour, cars that support higher charging rates are likely to avoid slower stations altogether in favor of faster ones, so there is certainly an incentive to install faster equipment in the future.

More important, many new installations are organized by enthusiasts who are interested in supporting the widest range of vehicles possible. For example, Plug-in North Central Washington is in the process of installing high amperage level two stations ("hal2", or in this case, Clipper Creek CS-90 units) in tourist areas throughout the north central part of the state, as well as electrifying Highway 20 across the North Cascades. They have already secured their first three units, and have entered into contracts with the host sites. Similarly, a project is underway to place a hal2 unit in Port Angeles on the Olympic Peninsula.

As much as we would like to see superchargers everywhere we want to travel, I simply do not think that is possible, at least not in the near future. There are many popular routes and destinations that will not be served by superchargers. Both commercial networks and groups promoting EV and economic development will step in to fill the gaps. Given the popularity of the Model S and the projected growing use of the TM drive train, I anticipate that we will see many more hal2 stations in the future.

As @PatT says, the J1772 standard supports up to 100 amps and uses the existing J1772 adapter. Clipper Creek also makes a CS-100 J1772 station. However, for some reason, the CS-100 is now limited to 75 amps rather than the expected 80, while the less expensive CS-90 supports 72 amps (80% of 90). Moreover, there is a glitch in the Roadster that does not allow it to charge at all if it senses a pilot signal in excess of 72 amps, so the Roadster cannot use the CS-100 unless it is further stepped down to 72 amps. For this reason, the CS-90 is the station of choice. It supports all vehicles (including the Roadster), and it gives you a charge rate almost as fast as an HPWC.

How does a 90 amp charging station work? Wouldn't you need 2 cords to utilize the twin charger on the car?. Do these stations have 2 cords? If never been to a charging station so I don't know.

@hademarco, No, it uses a single cord with a J1772 connector. It looks like any other J1772 station, and works the same way in the car. The twin chargers are internal, and share a single connection. The only way you can tell that you have twin chargers is to try charging on a high amp station, and see that the rate is higher.

One other consideration, if you're needing some juice in a town with a Tesla Store or a Tesla Service Center, they have HPWCs or Roadster wall chargers with a adapters for the Model S.

In Austin, the HPWC at the Service Center is only available during business hours. The HPWC and Roadster chargers at the Store (Gallery) are in a parking structure and available 24/7.

Sorry for what is probably a question with an obvious answer to many of you but here goes. Can I use a Tesla store's HPWC to charge my Model S if I do NOT have twin chargers? I think the answer is yes, but I just get a slower charging rate. Is that right?


Your answers are correct. Single charger car can use high amperage HPWC at Tesla stores. Yes, its maximum rate would still be single, not twin chargers. Yes it'll be slower.

So pay up a little at the time of order for twin speed or pay up a lot in money and time to upgrade later when you want to save charging time in future.