I guess saving five minutes on a road trip, the only time you should really SC anyways, isn't that attractive to me.
When you arrive at a location would you like to plug in straight away or wait 5 minutes? Besides reduced charging time, you also have increased capacity per stall, and reduced waiting time. It's good in multiple ways.
What does waiting time have to do with it? Many people, especially apartment dwellers that must rely on SCs only, charge to at least 90 percent. Total time of charge is barely affected since the envelope of full speed charging is so small. This is in addition to the fact that Tesla has started implemementing time limits at some SCs, often 40 minutes. So another check against "more likely to not have to wait". What does "increased capacity per stall' mean?
I think he's referring to queue theory. That 5 minutes might not sound like a lot but when things get busy, the line can grow and really cause a backlog. By shaving just a few minutes off a charge, they can increase the number of charges each stall can handle per hour.
If only 20 percent of stalls are capable of that charge, and only a tiny proportion of CCS cars can charge at that rate, then it's likely those cars that can charge that fast will often have to occupy slower stalls, or wait for the faster stalls specifically. The argument for this approach actually gets weaker the more congested the station is, as it becomes more unlikely that 350kW vehicles can charge at a 350kW stall. It's much more complex than basic queue theory. This is to say nothing of the fact that those stalls are more expensive, and that another "only" 150kW stall would be more useful.
Yes. While people currently are concerned about coverage, capacity is the real challenge for EVs. More capacity required means either more locations or more chargers in a single location. We know how time-consuming securing suitable locations can be, and that some sites are limited in the number of stalls they can support. Faster charging helps the charging driver, helps the approaching driver and helps Tesla.
They would just have to make the 350kW chargers cost more. (If they aren't more expensive, they might as well all be 350kW chargers, even if a site has a limited total capacity.) If they cost more, people with slow-charging cars would go to the cheaper chargers.
That would be an option. Then they'd probably need to charge Leafs charging at 35-45kW even less, but then again, the whole point of the operation is to rip off EV owners with slow DC charging.
The actual peak in practice is lower, yeah. However the the 90 miles in 30 min is real and confirmed (but not directly by me because I didn't bother with the DCFast). On the >50kW charger you'll see more like 100mi starting from a low SOC.
They say 90 miles in 30 minutes. 90miles/55kW*0.5h = 3.27 miles/kWh. 90miles/50kW*0.5h = 3.6miles/kWh 90miles/45kW*0.5h = 4 miles/kWh. Bolt EPA Highway rating is 30.5909kWh/100 miles ~= 3.27miles/kWh Note that the EPA ratings include charging losses.
Bolt in practice is approx. 4mi/kWh at 60mph (w/no HVAC or uphill elevation change, ambient temp between 65F and 85F, no headwind) w/o the AC->DC conversion losses, which don't apply with DCFast. On a good day you'll get the 90mi in 30 minutes on the 50kW chargers, more like 100mi and change on something with a higher rate ceiling. EDIT: You do still get a bit of charging loss with the DCFast, because part of the time HVAC runs for battery temp moderation to protect the battery. How much depends on ambient and battery temp when you start. But it's really modest losses.
Personally, I expect 150kW to be mainstream for normal cars for now. 350kW might be useful for things like buses and RVs though.
I'm expecting buses and RVs to follow Tesla's upcoming Megacharger standard for the Semi. We don't have a lot of details on it, but the plug they showed looks like four stacked Supercharger pin sets, so probably 5-600 kW peak or more. Vehicles that large can't fit into the area many Superchargers are in, anyway.
If Tesla uses modularized V3 SC, instead of V2, and run four of those parallel [w/liquid cooled cable] expect more like 800kW peak, which is more in line with the napkin math requirements of their 400mi in 30 min goal. Agree on the point about larger vehicles not mixing well with current SC locations, although I'm not sure how much Tesla is really interested in buses? City transit tends to have a lot more engineering room to work with alternate fuels, and inherently centralized infrastructure already, so Tesla is likely to just let others take over that. We've seen a good deal of reluctance for other companies to get on the Tesla SC standard in any way. Now that Tesla is moving past it's more fiscally reckless stage that removes part of the motivation for that, but I see am not convinced anyone yet is going to go there.
Wow. You'd think they would be able to throttle them down to 50 kW instead of turning them all off but maybe they need to do safety inspection before allowing that. Oops!