bkp_duke
Well-Known Member
Comprehensive auto insurance in the US covers accidents like this one. Sort of wife insurance?
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Tesla, TSLA & the Investment World: the Perpetual Investors' Roundtable
- Thread starter AudubonB
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Comprehensive auto insurance in the US covers accidents like this one. Sort of wife insurance?
petit_bateau
Active Member
Realistically, a good source for data like this would be scope 3 emissions and raw data.I haven't seen a pic of the Hawthorne Design Center "Supercharger Dashboard" in a while (the one below is from several years ago). You could estimate monthly usage from a heavily used site to get some idea of what it would take to offset with solar + storage.
I think I also saw some stats of overall energy for the whole network somewhere... maybe the annual report?
2019 datapoint 72 GWH a month.
If we assume 100 GWH a month, just as a round number, an avg selling price of 40c kwh, purchase price of 20c kwh, then monthly revenue is 40M, costs are 20M (not counting for depreciation, operation, etc). Installing a megapack would reduce capacity charges and [some, but insignificant] peak charges. In the best case let's assume, bringing avg purchase price to 10c kwh. This would yield savings of 10M a month, funding for 4 mega packs per month.
Again, this has a lot of assumptions. Such a capital expense would only be warranted for only the busiest chargers. And I've not even began to price in in-situ solar.
High utilization is a must to make any ROI on SC+megapack scenario. Makes much more sense for the truck stops, and of course, utilities, where utilization will be high.
Current business model for SC is to just pass through the pricing to the customers + modest (~10%) margin. Simple business model, easy to understand and does not require capital tie-in or huge battery volumes, which are scarce till master plan III is in full swing...
If we hear more reports of Teslas having problems, then I'd be more inclined to think the EA chargers are at fault. Vehicles should be able to regulate how much current they are taking in. For high power, DC fast charging of non Tesla EVs, EA is the main provider by a decent margin. That could explain why most of these issues seem to showing up on their equipment. But it could be the EA equipment that's mainly at fault.
2daMoon
Mostly Harmless
For them to weld together the contacts where the connector is attached to the vehicle will have some particular combination of heat and current (producing the heat) which will exceed the rating for the components. Only then will those contacts melt into each other or heat deforms the plastic in such a way that the connector cannot be removed. (An irremovable connector happened to both the Rivian and the Lightning)
The charger should be designed to prevent this scenario, even if the vehicle is at fault. Not doing so creates a situation where a charger can be disabled, requiring repair, due to a vehicle fault.
Installing a thermocouple or infrared sensor in the connector body could detect the encroaching heat even if produced on the vehicle side and then throttle down the charger or turn it off before damage is done.
There is no good reason to avoid designing a charger in this way. It will in no way affect the max charge rate, as the connector should already be designed to accommodate that. It would allow the charger to remain in use once the defective vehicle is removed.
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That's exactly what it DID! It FUSED with the cars it was supposed to be charging.If only someone had told them about this brand new concept of "fuses".
Shall I see myself out now?
2daMoon
Mostly Harmless
That is what we decided to do. We are away the better part of February, returning in Marvh. Temperature will rise again do we will not need the heater for the time being. First things first and that is to get rid of that stupid tax bill.
No, they can't. That isn't how DC fast charging works. It works by the car connecting the HV battery directly to the DC pins of the charge port and sending commands to the outboard charger to control voltage/current. All the car can do is monitor it and stop things if the charger sends something beyond what was requested. (But there is a response time involved there, so you can't stop a surge by any means other than a fuse.)
There is a thermocouple in the connectors, but this issue isn't caused by a gradual thing. In the case of the Rivian it happened about a minute after he plugged in. Charging takes ~30 seconds to start. So, nothing had really even started to get warm. It was something that happened instantaneously. (I'm just guessing, but I suspect the EA charger short-circuited, and drew massive current through the connector until a fuse blew.)
BTW: The cables aren't designed for continuous use at the full capacity. They use the thermocouple to monitor and adjust the maximum allowed at that instant based on how warm it is. (Which is why when the thermocouple fails on EA stalls that they limit it to charging at 34kW, since they have no way to know how hot the cable/connector is.)
Well, the BMS should be able to regulate DC fast charging to the extent that if incoming current is in excess of the battery acceptance rate, charging is immediately stopped. But there is definitely a communications problem between the vehicle and charger for that to happen.
Like @MP3Mike wrote, the only direct control the BMS has is to blow the pyro fuse or open the contactors while under (over)load.
The EVSE should not be supplying more current (nor voltage) than requested, and definitely not more current than the connector can handle.
Or to send a non negotiable command to the EVSE to cease and desist. Sounds like a communications/design problem. Better integration is obviously needed.
...
If the EVSE is already not doing what it is supposed to, how are you relying on it to react to an additional command?
I suppose there could be a pure hardware disable signal on a separate pin... However, dropping the pilot signal should already terminate charging.
It appears I have to take full responsibility for today's profit-taking. I will try to stifle my exuberance for the coming year so that this will not happen again.
Just add support to the Tesla charge cable and implement plug-n-charge while you are at it. Requires some coordination with Tesla, but considering the alternatives probably worth it.
Seriously insane that this situation seems to have gotten worse in the past 3 years. Imagine if some Exxon stations had bad fuel that caused car engines to seize up. It would be a huge deal. Since it's not Tesla apparently ?? media ignores it entirely?
Every EV review in the US should say "Public CCS chargers tend to have sub 50% uptime and can brick your car, Good luck out there!". I suggest they say this right under the line where they say "Much better value than a Tesla".
Fortunately for GM & Ford, Consumer Reports won't count this against them on their annual "Reliability Report" either.
Krugerrand
Meow
I predict at some point the X will in fact be a collector’s item along with a few other Model S configs, perhaps early Model 3 employee cars that had a few specials on them.
Krugerrand
Meow
Hmm 17 ships with 2000+ Teslas on each? Solid chance that's more EVs than GM or Ford produced in the entire previous 12 months. On the water floating to their final delivery point. Not counting Teslas on trains, Semi car carriers, or sitting on a lot waiting for the Uber to pick up the customer.
You wrote "So, CCS required". But what is the force of law, or of regulatory action, or enablement/refusal, of the word "should" in this context?
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