Dual chargers

[Canuck]

And it's not like you need fast charging when you stay over night at a hotel.

After driving all or most of the day, many people like to check into a hotel, unpack the car, have a shower or whatever, then go out on the town for the evening. During that hour or two while getting ready to go out, dual chargers make a big difference in getting the range needed for the night out.

IMHO, destination charging is headed for oblivion.... While I'm sure there are hundreds of people who don't mind sitting around for hours while their car charges, AC charging, 40A or 80A, other than overnight, is far too slow to be generally acceptable.

Headed for oblivion when more and more are being installed every day? That's a strange way to become obsolete. And what's wrong with getting 56 miles in one hour? If I arrive at a hotel at 4 pm, I can get 112 miles by the time I go out to dinner at 6 pm. How much more do you need to drive around town, assuming you arrive on empty which is also unlikely. And there's no need to "sit around for hours" when you usually have other things to do when arriving at a hotel.

 

[David99]

After driving all or most of the day, many people like to check into a hotel, unpack the car, have a shower or whatever, then go out on the town for the evening. During that hour or two while getting ready to go out, dual chargers make a big difference in getting the range needed for the night out.

If you have been driving most of the day, as you say, you are not going to drive another 60 miles just to go out for dinner. I'm all for fast charging. There is no reason to charge slower than you can. I'm just talking from experience of almost 50k miles with my Model S. At first I regretted that the sales person talked me out of getting the dual charger. Now that I have driven my car quite a lot including many road trips, there was never a single situation where the dual charger would have given me any advantage or where the single charger didn't cut it. It would only have cost me more in several ways. It would have cost me (back then) $1200 for the extra charger + $1200 for the HPWC. The installation of 100 Amp vs 50 Amp would have required a new panel and new underground wiring vs just one 14-50 outlet. They quoted me $2k for it. Yet it would never have given me any benefit charging at home. I have never not been able to fully charge at home with 10 kW.

I always hear the hypothetical scenarios where the difference between 10 and 20 kW would be significant. ... if it happens. My point is, it just never happened to me in 47k miles of driving. And I think it happens so rarely that the sales people are always recommending against the dual chargers and ultimately Tesla now doesn't even offer it as an option when ordering. Installing two chargers in the factory is trivial. They are pretty much plug and play at that point. Installing it later is a pretty big deal in terms of labor.

If I had a hotel I would definitely not install an 80 Amp HPWC. I would install one limited to 40 amp and use the other 40 Amp to install an EV plug. Why would I limit the service of attracting EV drivers to Tesla only? I also know that even if a dual charger Tesla arrives totally empty, it will be full in 4.5 hours. I doubt the owner would want to move his car at 3 am and have a second one move his car in the spot. And I would not pay an employee all night just to sit there and switch plugs at night. Heck no, I rather have two 40 Amp chargers, both cars plugging in when they want and both be fully charged in the morning without any hassle. A positive side effect: This way both can use their app in the morning and pre-heat/cool their car from shore power.

 

[Canuck]

If you have been driving most of the day, as you say, you are not going to drive another 60 miles just to go out for dinner.

I don't know about that. You can put on a lot of miles touring around a new town on vacation in just a couple of hours. Also, in the winter, 60 miles is not actually 60 miles but my point was that you don't only need overnight charging when staying at a hotel. Quite often you just stop in and then go out. The more miles put on during that time, the better, especially to avoid range anxiety.

I always hear the hypothetical scenarios where the difference between 10 and 20 kW would be significant. ... if it happens. My point is, it just never happened to me in 47k miles of driving. And I think it happens so rarely that the sales people are always recommending against the dual chargers and ultimately Tesla now doesn't even offer it as an option when ordering.

It's not hypothetical to me. In fact, I used a Sun Country 70 amp EVSE the very fist weekend I got my car on the way to my cabin (and many times since). My sales rep also strongly recommended the dual chargers but that's probably because we have a lot of 70 amp EVSE's in this area and I told him of my driving plans.

It would only have cost me more in several ways. It would have cost me (back then) $1200 for the extra charger + $1200 for the HPWC. The installation of 100 Amp vs 50 Amp would have required a new panel and new underground wiring vs just one 14-50 outlet.

I put a 14-50 plug on my HPWC and plugged it in since I don't need 80 amps at home. I charge at 42 amps at home since it splits the load on the chargers (which are liquid cooled) to make use of both chargers rather than stressing out one. You don't need to rewire your home or use 80 amps with a HPWC since it has dip switch settings to limit the amps (and you refine that more in the car). Plus, a HPWC is now only $100 more than a UMC and it is much more heavy duty allowing you to keep the UMC in your trunk at all times. With another HPWC at my cabin at 80 amps, I can get enough charge in 5 hours to make a daytrip and get back home in the evening. I rent out my cabin (a lakefront vacation home) so I can switch over tenants and make it back without having to take the ICE. That's out of the question without dual chargers.

But to each their own. You're have no need for them whereas I would be restricted in my driving without them.

If I had a hotel I would definitely not install an 80 Amp HPWC.

I'm glad you're not in the hotel business!

 

[m6bigdog]

But you CAN use it every day at home with a HPWC if you have it configured for higher than 40 amps. The HPWC can be supplied via a 100 amp circuit delivering 80 amps continuous which will utilize the capacity of both onboard chargers.

What the HPWC is capable of and what the typical house is capable of supplying to the HPWC is two different things.

That is, charging an MS with the HPWC is a 100% load and at 80 amps when calculating the house service equipment necessary to supply the electrical equipment load it would most likely require a 175-200 amp service to supply 80 amps to the HPWC. Upgrading a service to 200 amps cost some serious money. Mine would cost $8-10k to upgrade (DIY cost much less but I need to trench across 16' of concrete driveway) so I will just live with 48 amps or 12kw charge rate until it need more, say with a second EV.

Also, at your home unless you have a second EV, charging all night is no big deal since there isn't another car waiting to charge. Hence in 6 hours 10kw charge rate will provide 174 miles of charge. At 48 amps is 35mi per hr. of charge and I'll get 208 miles of charge in 6 hrs. and that is good enough for most of what I need.
However, if it get home and want to go back out and I'm down to 25-50 miles range it will be close to 3-4 hours before I get back to 150 miles range at 35 miles per hr. of charge.

 

[mknox]

I always hear the hypothetical scenarios where the difference between 10 and 20 kW would be significant. ... if it happens. My point is, it just never happened to me in 47k miles of driving.

I think that is the key point. If you don't have higher power J1772 stations where you travel, then the value is minimal. It's just that around my frequently travelled area, there are quite a few 70 and 80 amp stations. In fact, I plug in to an 80 amp station almost every day and take full advantage of my dual chargers. The odd time I do plug in to a 30 amp Chargepoint or whatever, I find it frustrating realizing that I could be charging almost 3 times faster (big difference between a 1 hour stop and a 3 hour stop). For me, the big advantage of dual chargers was for when I'm on the road. Currently I only have a 20 amp 240 volt supply in my garage at home.

 

[tga]

Unfortunately the Dual Charger is no longer available as a factory installed option due to customer complaints and some misunderstanding about its usefulness when you can't use it every day at home with a HPWC or with the Universal Mobile Connector.

That's complete speculation as to why they made the change. We have no idea why it was done. Many have speculated that it was to streamline manufacturing, which, IMHO, is the most plausible explanation.

 

[ecarfan]

Unfortunately the Dual Charger is no longer available as a factory installed option due to customer complaints and some misunderstanding about its usefulness when you can't use it every day at home with a HPWC or with the Universal Mobile Connector.

Do you work for Tesla, so that you know that statement to be true? Or are you speculating?

I agree with you that Dual Chargers are useful. I got them in my S back when it was an option that could be ordered with the car so that it came off the line that way. I have 200A service to my house.

For those who cannot set up home charging at 80A I still recommend Dual Chargers because I think that over time higher amp L2 charging stations will become increasingly common.

 

[m6bigdog]

That's complete speculation as to why they made the change. We have no idea why it was done. Many have speculated that it was to streamline manufacturing, which, IMHO, is the most plausible explanation.

Not speculation from my sources, as that is what I was told with in Tesla when I initially couldn't get the Dual Charger option in my MS order, at the end of March.
So if you believe it is speculation, it is fueled by the Tesla Delivery Specialist staff as they never once mentioned anything about streamlining production. However, customer complaints and misunderstanding about the Dual charger & HPWC option functionality and usefulness since it was initially recommended to be include in every MS Order was mentioned several times on different calls by different Tesla Delivery Specialist and managers I personally spoke with.

As for the speculation that making the Dual Chargers an Accessory will streamline manufacturing is absurd.
Streamlining production is done by work motion studies, efficient and error free assembly not by deleting options and functional parts from the final assemble. I anticipated there is sufficient dwell time and opportunity at the assembly stations to install the dual charger during manufacturing even if the line was sped up.
Also each car spends hours at the end of line reconciling assembly error & omission issues that mutes any labor effort and/or assembly time to install the dual charger.

IMHO, installing the Dual Charger at the Service Center is as inefficient as you can get by any measure. As you can imagine the damage and additional SC problems that will introduced to each and every MS pulled apart to install the duplicate 10kW charger; let alone the waste of the customer's time. Therefore, the actual cost for SC install is huge compared the assembly line install and the additional $500 cost for the Dual Charger as an Accessory will not cover the actual cost.

 

[FlasherZ]

There was indeed some misunderstanding about the effectiveness of dual chargers with typical level 2 access points, but as I understand the streamlining of manufacturing and the popularity of the option is the primary reason for the change - at least that's what was in the communications to service centers.

 

[m6bigdog]

Do you work for Tesla, so that you know that statement to be true? Or are you speculating?

I agree with you that Dual Chargers are useful. I got them in my S back when it was an option that could be ordered with the car so that it came off the line that way. I have 200A service to my house.

For those who cannot set up home charging at 80A I still recommend Dual Chargers because I think that over time higher amp L2 charging stations will become increasingly common.

No, I personally don't work at Tesla however my source set up the initial Fremont production line and knows the MS intimately.

Also, the Dual Charger is a necessary component for the efficient utilization of the public charging stations, if not now in the immediate near term.
If you can charge twice as fast then twice as many EVs can charge given the limits of the charge stations at any one destination.
Therefore, if it takes twice as long to charge and all the charge stations are occupied and/or a few are ICE'd then the Queue wait to charge at a destination will be twice as long!!

I anticipate with the near term growth of EVs (236k for 2015, 2014 growth was 67%) and expanded Tesla Production the Superchargers and HPWC destination charge stations build out will be hard pressed to keep pace and if they don't the bottle neck for EV acceptance will not be range or charging time but the Queue wait at the public charge station.
That is a scary proposal!!

 

[mknox]

There was indeed some misunderstanding about the effectiveness of dual chargers with typical level 2 access points...

Not sure what that means. Are you saying that dual chargers are not effective with 80 amp J1772 stations or did you mean that the "typical" station is of lower power? For me, there's tons of 70 and 80 amp J1772 stations to choose from and I can attest to the effectiveness with dual chargers. (I'm plugged into an 80 amp public J1772 station as I type this).

 

[FlasherZ]

Not sure what that means. Are you saying that dual chargers are not effective with 80 amp J1772 stations or did you mean that the "typical" station is of lower power? For me, there's tons of 70 and 80 amp J1772 stations to choose from and I can attest to the effectiveness with dual chargers. (I'm plugged into an 80 amp public J1772 station as I type this).

The latter - you're just lucky with the prevalence of high-power J1772. The "average" public EVSE out there is a 30A model, unfortunately. Tesla tells people the easiest way is to install a 14-50 receptacle and charge completely overnight, not needing a dual charger. I'm guessing the customers weren't sophisticated enough to understand the relationship between dual chargers and high-power charging, or the prevalence of it (or lack thereof).

It's a bit of a catch-22, though, in that EVSE's aren't installed for high power because there are very few cars that can use them; and now we have a car that is getting single chargers by default which won't drive high power EVSE installation. Personally, I would like to see Tesla ship every car with 80A/96A capability to change the behavior, but I believe the pricing/margin concern doesn't allow for it. For the few who want it, it becomes a service-center installed option to keep the manufacturing lines simple.

 

[chriSharek]

The latter - you're just lucky with the prevalence of high-power J1772. The "average" public EVSE out there is a 30A model, unfortunately. Tesla tells people the easiest way is to install a 14-50 receptacle and charge completely overnight, not needing a dual charger. I'm guessing the customers weren't sophisticated enough to understand the relationship between dual chargers and high-power charging, or the prevalence of it (or lack thereof).

It's a bit of a catch-22, though, in that EVSE's aren't installed for high power because there are very few cars that can use them; and now we have a car that is getting single chargers by default which won't drive high power EVSE installation. Personally, I would like to see Tesla ship every car with 80A/96A capability to change the behavior, but I believe the pricing/margin concern doesn't allow for it. For the few who want it, it becomes a service-center installed option to keep the manufacturing lines simple.

Most of the L2s here in Florida are also 30 amps.

 

[SW2Fiddler]

I'm guessing the customers weren't sophisticated enough to understand the relationship between dual chargers and high-power charging, or the prevalence of it (or lack thereof).
... Personally, I would like to see Tesla ship every car with 80A/96A capability to change the behavior...

This is what I think we'll see:

No more default 10kW option. Service Center installation of "second charger" for those who got an S before they all started sporting the HA factory charger. (price of this has already started coming down)
Tesla ceasing "selling" the second 10kW factory-installed (already there) and just installing 20kW or 22kW capability on all new cars because It's The Right Thing To Do. Instead of waiting for buyers to grow out of "me, me, me, ME, I don't need a second charger so to perdition with all of thee!" It's true and reasonable that buyers would rather spend a hard-earned four-figure sum on a comfort/performance gizmo option than on a boring charger.
Tesla continuing to propagate Destination Chargers (TM HPWC + token J1772) instead of waiting for other companies to Up their Infrastructure.

It parallels what they have done before.

 

[TexasEV]

The latter - you're just lucky with the prevalence of high-power J1772. The "average" public EVSE out there is a 30A model, unfortunately. Tesla tells people the easiest way is to install a 14-50 receptacle and charge completely overnight, not needing a dual charger. I'm guessing the customers weren't sophisticated enough to understand the relationship between dual chargers and high-power charging, or the prevalence of it (or lack thereof).

It's a bit of a catch-22, though, in that EVSE's aren't installed for high power because there are very few cars that can use them; and now we have a car that is getting single chargers by default which won't drive high power EVSE installation. Personally, I would like to see Tesla ship every car with 80A/96A capability to change the behavior, but I believe the pricing/margin concern doesn't allow for it. For the few who want it, it becomes a service-center installed option to keep the manufacturing lines simple.

I agree with all of these points, but Tesla is compounding the confusion by marketing a destination charging program using HPWCs that can deliver 80A while selling cars that can only accept 40A unless the owner makes an effort to have dual chargers installed. It used to be the effort was just checking a box on the order page, now most mainstream buyers wouldn't even know the dual charging option exists and they won't get it installed at the service center if they aren't aware of it. Then they find a 80A HPWC at a destination and wonder why they only get 40A.

Too many people mistakenly thought they needed dual chargers to supercharge at the fastest rate and purchased the option when they had no need for it. That was a failure of education on Tesla's part and a failure of researching on the buyer's part. Now the best incentive for people to install dual chargers, which is the rapid expansion of the destination charging program, is being wasted by lack of awareness of dual chargers when prospective buyers look down the options list on the web site. High amp level 2's have been rare with exceptions such as Sun Country Highway-- but Tesla could have helped solve this chicken and egg problem by encouraging rather than discouraging the purchase of cars with dual chargers.

 

[techmaven]

Looking more long term, the L2 destination charging network needs to be able to charge future packs that have potentially much larger capacity in an 8 hour overnight window. Right now, an 80 amp 240v EVSE can charge an 85 kWh pack in under 5 hours. If and when we hit 135 kWh of battery pack capacity, we will need all 80 amps to be able to charge that pack from empty to full in under 8 hours.

The 40 amp charger, on there the hand, is already at the 8 hour border. Any significant pack capacity increase beyond the current 85 kWh is going to mean the need for an onboard charger that has more than 40 amps. Maybe you can get away without it for a 90 or 95 kWh battery pack, but if the battery chemistry improvements mean a 100 kWh battery pack ships in a Model S, the standard onboard charger will likely need to support more than 40 amps.

The advantage of a 80 amp EVSE is that it can be useful for far longer than our current viewpoint on electric vehicles, assuming the plug still exists. A 80A HPWC is also about 8-10x cheaper to install than a 24 kWh DC fast charger. But it isn't really intended to support long distance travel. In the end, destination charging is about long term stay - preferably overnight. 40 amps is definitely sufficient for overnight charging for our current battery packs, but the HPWC scenario with 80A is a good compromise solution between low cost and future proofing.

 

[mknox]

Looking more long term, the L2 destination charging network needs to be able to charge future packs that have potentially much larger capacity in an 8 hour overnight window. Right now, an 80 amp 240v EVSE can charge an 85 kWh pack in under 5 hours. If and when we hit 135 kWh of battery pack capacity, we will need all 80 amps to be able to charge that pack from empty to full in under 8 hours.

This is my thinking exactly. EVs are certainly only going to come with larger batteries and more capable onboard chargers over time, so installing 30 amp public EVSE is extremely short-sighted in my view. This is part of the reason I installed 2-100 amp (80 amp continuous) chargers at my company's workplace. The other reason is that even though one might have a whole 8 hour day to charge their car, if EV adoption picks up and multiple cars have to share, then being able to charge quickly and move on to the next car starts becoming relevant.

DC Fast Charging is, of course, another option, but due to the cost and complexity I see that as really more about inter-city travel and not about home, workplace or destination charging.

 

[Larry Chanin]

Most of the L2s here in Florida are also 30 amps.

30 amp level 2 chargers may be useful now for an overnight stay at a hotel, but for the most part they are not very convenient for Model Ss that are doing anything beyond a daily commute. I am pleased that Tesla sees the value in aggressively expanding the high capacity Destination Charging network in Florida in anticipation of future charger congestion.

Hopefully Tesla will see the logical inconsistency of rapidly expanding a high capacity charging network, without offering the option of installing dual on-board chargers at the factory.

Larry

 

[ItsNotAboutTheMoney]

In a world where BEV is king, you will want fast DC chargers everywhere.

Now you choose:
- You can add a 2nd 40A AC charger to 12 cars.
- You can make a pile of 12 AC chargers that can be put in a Supercharger.

At destinations choose:
- 1 x 80A AC EVSE
- 2 x 40A AC EVSE
- 1 x 2-plug 80A EVSE, max 80A total, max 80A on a plug

Seems to me that given average use, 80A AC will be a high-end, marginal option.

 

[brianman]

At destinations choose:
(1) 1 x 80A AC EVSE
(2) 2 x 40A AC EVSE
(3) 1 x 2-plug 80A EVSE, max 80A total, max 80A on a plug

I'd love to see Tesla offer #3.