Tesla does load balancing and load limiting at its superchargers. Although most 
of their stations are rated at 120, 135, or 145 kW, they usually deliver less 
based on these factors:

-utility ordered power limits. Drivers see this when their low SoC cars start 
out with high kW and in under a minute that drops into the 60s. Presumably 
Tesla is on a rate plan that requires load curtailment when the utility asks 
for it.

-equipment overheating of either the superchargers themselves or charging 
handles. Sometimes drivers switch station stalls in an attempt to work around 
this.

-shared power between two charging stalls. Earliest car gets priority. Reminder 
goes to second car. Stalls are labeled so drivers can avoid using the paired 
stall if they so desire.

-battery BMS. The BMS limits charge rates. Owner gathered info says factors 
include battery SoC, battery model (kWh rating), version (v1/v2/etc), chemistry 
(silicon added or not), age (time/days/months), usage (lifetime kWh in/out), 
health (usable energy vs design energy), temperature (above 40-50 F, below 
90?), and probably other factors. 


Some these same things have been done with certain OpenEVSE builds.


On February 8, 2018 10:20:13 AM CST, Dan Kegel via EV <ev@lists.evdl.org> wrote:
>On Wed, Feb 7, 2018 at 2:30 PM, Robert Bruninga via EV
><ev@lists.evdl.org> wrote:
>> I wonder how big a flywheel is needed to store the energy to charge a
>250
>> mile range in 20 minutes?
>> Since it is fixed, and does not have to be in a vehicle, it might be
>the
>> answer to large charging stations.
>>
>> When ten TESLAs pull up at ten fast charge cords at the same time,
>that is
>> over a megawatt of needed power... in 20 minutes...
>
>That application doesn't capitalize on the flywheel's ultrafast
>charging and discharging abilities.
>And smoothing can be done by modulating the teslas' charging rates.
>
>But hey, who knows.  See
>https://scholar.google.com/scholar?as_ylo=2014&q=flywheel&hl=de&as_sdt=2005&sciodt=0,5&cites=16378509166563059026&scipsc=1
>for recent related papers.
>- Dan
>_______________________________________________
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