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Is there a downside to free Supercharging?

As a planned 2013 Model S owner, I'm sure I was excited by much of the news yesterday as everyone, although I was hoping to hear more about infrastructure in Texas where the Superchargers will be vital to using anything but the 85 on common cross-state routes.

Making products free is unequivocally good on one level, but I wonder whether this will end up being an unwise decision. It seems to me that making use of the Supercharger free will modify its use from a "distance refueling" option to an option preferable to recharging at home for many cost-conscious consumers who live in the vicinity of such a station. If these stations' capacity is being dominated by those who are looking to avoid home-charging costs, does it then make the network less useful and more frustrating for the cross-country travelers for whom I think the system was originally developed?

I think it's clear Tesla have done something revolutionary here, so I hope this is interpreted as the "unintended consequences" post it was meant to be and not undue criticism of one of the first truly novel and exciting things to come out of autos in years.

What do you all think?

Tesla/Elon made it clear that superchargers should not be used on a regular basis. I doubt people will use them to recharge their batteries on a daily basis as it just isn't designed for that.

That's my 2 cents...

I also don't have even 30 minutes per day to sit there waiting for my car to recharge. I'd much rather have it in my garage charging while I sleep.

I agree with RobertMontreal. I doubt people will make a special drive to charge when the cost at home is so low already. $0.12/watt-hr is not going to be worth it, particularly if you can afford a Model S in the first place. It's the same reason most people have pizza delivered rather than picking it up, even though it costs more.

No one wants to be bothered to take a drive, spend 30 minutes or so standing around and then drive home when there's an outlet right next to their car in their garage.

I'm sure overfrequent supercharging will result in damage to the battery at some level.

Then again...maybe not. According to the No Limits post, there's no damage done.

Ok so if there is no damage/down side and their system can talk to the car to control the charging, I then ask why is this not standard on the 40kwh battery or at a minimum an option.

I am not saying we should expect to go cross country in this size battery but if your doing a run on the highway at 70+mph your going to burn the battery quickly and why not have the ability to top it off at a local pit stop...

I am thinking the NJ garden state parkway where if you drive under 70 during rush hour you will get run over.

If the iMev and Leaf can do this the Tesla should be able.

It makes sense that they try out the Super charge stations in Ca. where they can keep an eye on them, but like Walrus said, here in Texas we are SOL in some areas where we may not see a service station for 100 miles.

So my question is this, is it currently believed that normal service station may allow a green car to pull up and plug in? I would think these superchargers would become something the common service station would install like a an air pump from a third party.

Will the technology be allowed for third party developers to sell to Shell? Seems like a no brainer.

@murraypetera: You can drive the 40kwh version at 70mph just fine, it just depends on the distance, AC use etc.

I think Tesla just made the (in my opinion, reasonable) business decision not to offer the upgraded wiring, etc for the smaller battery. Those that want the added flexibility need to upgrade to the 60kwh battery.

@murraypetera - you can already charge the 40kWh battery at essentially the CHAdeMO charging rate of the LEAF (20kW) if you buy the dual chargers and the HPWC.

The 40kWh battery has fewer cells in parallel (the voltage will be the same) and the charge rate of individual cells is the same, so the maximum charge rate of the overall battery is lower as well. I suspect the 60kWh battery will also get fewer miles add/hour at the Supercharger for the same reason - it should work out to the same %-SOC increase per hour of supercharging, regardless of the battery size. So, you can expect to get 50% of your range in half an hour, regardless of the size of the battery.

Given that, there is no point in using a Supercharger for the 40kWh battery over a regular 100A@240V HPWC.

Unless I am missing something the Super Chargers do not event support the AC Level 2 charging for the 40 KWh battery.

If we were to follow 50% rule you have than the 40 KWh / 160 mile battery would get 80 miles in 30 min which is about 3X the twin chargers 62 miles/hr. I would be very very happy with this. Heck 60 miles in 30 min would make me ecstatic.

My gut feeling is that this is a marketing decision not a technical one. Tesla should be treating all of us early adopters very very well so we go out and tell our friends how great the car is.

And I did order the twin chargers with the 40 KWh just so when I need an extra 30 miles I do not need to wait an hour on the Garden State PW but I will have a very hard time to dig up the extra $10,000 cash for the DC quick charge.

For me it was get the basic car no options and the bigger battery or the options. Not all of us have the extra cash for everything. I am doing all I can to support Tesla with a $40k deposit for over 2 years now. (I down graded when the pricing came out)

@murraypetera
Unless I am missing something the Super Chargers do not even support the AC Level 2 charging for the 40 KWh battery.

No, because the superchargers are for people traveling long distances, not commuters. One of the reasons they probably didn't make the 40kwh cars compatible with the superchargers is that they don't want all the supercharge stations occupied by people who can't road trip anyway.

Tesla should be treating everyone well, and they are. There's an explanation on a related thread giving lots of reasons Tesla is not supporting the 40kwh batteries with the SCs for technical/financial reasons.

I hope you recognize that what you're asking is to get stuff for free. It really does cost Tesla extra money for the wiring, hardware, etc, and all the folks at Tesla work hard and deserve to get paid for their labor and materials, plus a profit. As idealistic as Elon Musk is I doubt even he would be doing this if there were no profit in it.

I'd love an airplane, but life is about trade-offs. If I ever do scrape up the money for an old Cessna I'm not going to complain if it doesn't come with a glass cockpit and can't go as fast as that other guy's Lear Jet.

On 40KWH pack supercharging-

TM isn't holding this back for cynical marketing reasons, it's a technology-driven decision.

The engineering problem for 40Kwh packs is nontrivial with today's batteries.

There are many issues -

1. The 40KWH pack uses less expensive cells that aren't as advanced in their cell chemistry. That means you must constrain charging more to guarantee long life.

2. The circuitry and wiring to accept hundreds of Amps of DC current add parts that cost money. This doesn't allow the favorably low entry level price point.

3. Since fast charging works as a percentage of capacity, a half-size battery means only half the miles gained in a 30 min charge. Those numbers don't deliver the benefit a road tripper wants from a fast charger.

TM's engineering choices are honest and intelligent. Whenever there's an amazing deal like the free supercharging, everyone wants in. (Even those who don't pay for the equipment to do it.) Taken to logical extreme, some might ask "why don't they make the car free too?" But that's obviously unsustainable.

To do the hard work to make all this possible costs money so they have to charge a fair price to deliver them to more people. They did an honorable and smart job optimizing the benefit at each price point.

The 40KWH car is no slouch either. It's an extraordinary deal for the city commuter. Unparallled safety, ride, fuel economy, roominess and beauty. It offers all those benefits of the fancier model, but just not the road trip range.

The notion that you add in the road trip range and now free charging for 10k more is mind-blowing.

The SuperCharger strategy is a brilliant hit out of the park. Elon wasn't overstating the significance when he used the term "historic".

I hope those of you who are ordering twin chargers realize what they do and do not work with. You are not able to connect to two power sources and get double charge rate. They are specifically for the HPWC. If you are thinking that you can get a 62 mph charge rate just because you have twin chargers you will be even more upset after getting them and finding they do not do what you expected.

@Theresa:

They will also allow you to get up to 20kw charge rate at those public stations with sufficient amperage.

Just because the high amperage level 2 chargers are extremely rare right now, (I only know of one), doesn't mean they won't become a lot more common fairly soon.

Well the assumption is that the superchargers have some value to users, so they might be willing to pay something per use for it right?

However, free supercharging could incredible marketing value that actually feeds back into the installation of more superchargers. Access to superschargers reduces or eliminates range anxiety -> lowers objection to buying -> more Tesla car sales -> More users -> more capital* to build more chargers?

*I don't know who pays for the installation, Solar City, or Tesla?

Either way, collectively, they have incentive to install as many as possible if it's really true that there will be net electricity production which can be turned into profit.

Elon said the the stations are really cheap to throw up. The big expense is the solar panels, which belong to Solar City. It's almost a free ride for TM.

"free supercharging" is probably more than covered by $600 annual maintenance cost. Hidden cost there. Also charging there would be maybe 5% of all driving, so very few people would be actually charging there so money would not cover the building those unless they would increase the cost to insane amounts, and then no-one would be charging there. It's a no win situation to cover costs by charging fee.

As one 80% charge of 85kWh costs somewhere in vicinity of $8 in home you could not get even one of those build with that cost, so money have to come from other source, and if it comes from other source then you can as well give it "free" to anyone buying Model S and hide that tiny cost there.

This actually explains the "too high" annual maintenance cost. It maintains those supercharges, not only your car. As such I now understand the annual cost.

@Timo;
It might seem like that from the user's POV, but TM has nothing to do with the electric bill payments, unless you mentally merge Solar City and Tesla. TM builds the non-solar charging infrastructure, and SC links all the stations together with their solar cells at those stations possessing them and a) charges the cars from the grid, and b) feeds the solar panel output into the grid. They build out enough panels (in suitable locations) to make sure b>a, and that their income from power FIT sales exceeds the cost of charging the Model Ses that use the chargers.

Note that nowhere is TM, or its service revenues, involved in those transactions. SC essentially franchises the stations, and maintains them. Once built, TM is almost hands-off. That is quite clear from Elon's description, and is why he is so elated. The business model is actually a low-cost one time per station marketing investment that pays off forever. What's not to love?

I misspoke in saying "links all the stations together". Of course there is no physical connection, just an organizational/bookkeeping one.

I don't expect this will be an issue in the short term, but one possible downside of not charging for charging is congestion. If a supercharger is at a place remotely interesting (sounds like one of the first six is at an outlet mall) I can see people parking their car, plugging in and shopping for a couple of hours. The Volt owners at my office complain because the landlord's Semacharge charger charges them as long as their car is plugged in even when it's fully topped off. I have thought that seems like a pretty good idea so one car can't monopolize a parking spot/connection all day.

Maybe the Supercharger should be free for the first hour, then start ramping up over time. $5 for 60-90 min. Another $10 for 90-120. $50 per hour after that.

@MandL: Good point.

MandL: I guess there is a difference between "charging" and "parking".

But this is not unique with the Tesla SC. Any publically available charging device has this same issue. Have some kind of "public charger rules" been developed? Should we ask Miss Manners?

I would think the charger should hang from some overhead rotating arm, and a new arrival would be allowed to unplug a fully-charged vehicle.

Question: who provides the capital to build the SuperCharger network? Tesla does not have the capital to do so (witness their need for secondary financing just to ramp up manufacturing). Solar City is not public (yet) and I think they rely in bank financing to cash-flow the solar systems they own.

Maybe this is part of Solar City's pre-IPO strategy, use debt to build out the initial stations, show cash flow in excess of debt service, then go public?????

Considering that they only charge the Tesla Model S I don't think there is much worry about cars sitting at the chargers all day for quite some time.

It's not like they are at a place that most people will hang out that long. Chargers at work locations will have that problem since people will pull up in the morning, plug in and go to work for 8 hours.

I don't see someone with a 250+ mile battery going on a road trip and spending the whole day at the shopping mall. I'll admit I've seen my wife and my mom take the whole day shopping but typically never more than a few hours at one mall or store. When it is a full day shopping spree around x-mas they make trips to the car to drop off packages. At that point they would surely move to a closer parking spot particularly if someone waiting on a charge was glaring at them.

Now that California has adopted the driver-less car rules (I think) they can have the car unplug itself and park out of the way :-)

Charging/parking abuse...

Charger locks and disables the car after 1 hour, fee to unlock $200 per hour parked, payable to the local municipality. That pays to go after the "just parking" customers, recorded on camera, same hourly fees payable to the town. Display the price list prominently at the site, just by the "Welcome" sign.

:-P

@ Tiebreaker - a little harsh. I'd hate to have to stress out that I can't order dessert if I order a meal while I'm charging.

Im sure something will evolve to handle the problem of supercharger hogs if it materializes.

Since the whole point of the stations is to load up on electrons and get back on the road as fast as possible, I see this as a non-issue.

It would be sufficient to have, say, a flashing red light atop the charger when the designated charge level had been reached (remember the "50% charge" is not a fixed ceiling or quantity. You can DC-charge more if you're prepared to wait.)

Seems like this will ultimately be a non issue. The primary reason for using the supercharger in the first place is to get back on the road with sufficient energy to reach your next charging point or destination.

The principle use for a road is to drive along it, yet people still park on it when want to, as opposed to driveways and parking lots.

This has the potential to be an issue, but I don't believe it will be one for a few years. Hopefully we can come up with something in time.

People park in the parking lane on roads, otherwise they get a ticket and/or a tow. I have no problems using roads because of people parking. By Vawlkus analogy that translates to having no problems with people using charger.

It might be a problem in a few years... 2-10 years depending on how soon the BEV market takes off. By then batteries will go much further and superchargers will be needed much less (but for longer at one time). Tesla will probably upgrade them as batteries change.


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