So a week or so ago, I'm at the North Houston combined SuperCharger and Showroom. I deliberately ran down my SOC to about 3 RM to see what kind of current the chargers would give me. Since it was close to dawn, I had all six SuperChargers to myself.
Temperatures were hovering around 27ºF, and this had persisted overnight. Car had been driven at highway speeds for the previous 30 minutes and a 35 MPH for 15 minutes prior to that -- so it was as warmed as it was going to get from driving. Reaching the chargers I found this pattern. Plug in; 30 second ramp to about 110 kW; sustain for 60 seconds; drop to 70 kW (or so) in next 60 seconds. I did this through the entire set of charging stalls 1A through 3B. Through all six, not one could manage 75 kW after being plugged in for 2+ minutes. My pattern was to move to the next stall immediately after this precipitous drop.
Now, I've seen posts where individual stalls are all wonky, and a move gets you to a suitable kW on the charging curve. What would cause the entire site to behave with such lowered output? My theory is that maybe the utility had something to do with it -- but the weather was clear, and as far as I could see, there was no stress on the electrical grid.
Temperatures were hovering around 27ºF, and this had persisted overnight. Car had been driven at highway speeds for the previous 30 minutes and a 35 MPH for 15 minutes prior to that -- so it was as warmed as it was going to get from driving. Reaching the chargers I found this pattern. Plug in; 30 second ramp to about 110 kW; sustain for 60 seconds; drop to 70 kW (or so) in next 60 seconds. I did this through the entire set of charging stalls 1A through 3B. Through all six, not one could manage 75 kW after being plugged in for 2+ minutes. My pattern was to move to the next stall immediately after this precipitous drop.
Now, I've seen posts where individual stalls are all wonky, and a move gets you to a suitable kW on the charging curve. What would cause the entire site to behave with such lowered output? My theory is that maybe the utility had something to do with it -- but the weather was clear, and as far as I could see, there was no stress on the electrical grid.