I've come across several threads that discuss the various energy consumption display... some of which were as much conjecture as anything... which is understandable given that we are all guessing at exactly what our Model Esses are doing under the covers, and the fact that he official guides are relativity light in discussing the subject.
I am trying to reconcile my personal experience based on my understanding of what information the car is presenting to me in the several areas regarding charge and range. In other words: "Where's my energy going?"
BACKGROUND: In my month+ of ownership, it's been my experience that after a charge, there is some energy usage at rest (aka the "vampire loss"). I've also just hit a lifetime average of the magical 308 watts/mile (after 3000 miles on the odometer).
I also just took two 500-mile road trips, on one of which I had opportunity to drive the S from a full-range charge down to 0 miles (actually about a mile past).
All numbers used in this post are with the displays set to "Rated" miles.
OBSERVATIONS: Here is what I've noted regarding the displays-
CONCLUSIONS/QUESTIONS: I have a few conclusions, but each seems incomplete and raises additional questions. Particularly I'm trying to figure out where energy used for non-locomotive draws (A/C, headlamps, heat, pack thermal management, etc...) is accounted for:
3. The console energy app would seem to think that my averages would give me more range than my dash does. Which is right? Does the console ignore non-locomotive energy draw?
All in all, it feels like the speedo-range estimate is "safest"... primarily because it seems like the most conservative. However it does feel like there's a disconnect in that even when using 10-15% less energy driven than the rated estimate of 308 W/mi, it still counts down faster then miles driven...
Any thoughts appreciated.
I am trying to reconcile my personal experience based on my understanding of what information the car is presenting to me in the several areas regarding charge and range. In other words: "Where's my energy going?"
BACKGROUND: In my month+ of ownership, it's been my experience that after a charge, there is some energy usage at rest (aka the "vampire loss"). I've also just hit a lifetime average of the magical 308 watts/mile (after 3000 miles on the odometer).
I also just took two 500-mile road trips, on one of which I had opportunity to drive the S from a full-range charge down to 0 miles (actually about a mile past).
All numbers used in this post are with the displays set to "Rated" miles.
OBSERVATIONS: Here is what I've noted regarding the displays-
- Dash "Speedo Range": After a "standard" (90%) I typically have on the order of about 242 miles of range. A "max" (100%) charge nets about 270. For both my normal driving habits, as well as the road trips, my miles driven have always been less than what the speedo range estimate has been. On one leg of my road trip, I drove a mile past 0 in to "CHARGE NOW", despite having started with 270 miles estimated, and only 245 miles driven, and my reported trip average being below 308 W/mi.
- Trip Meters: After a standard charge, which ends a couple of hours before I leave in the morning, my trip-meter w/mi "Avg since last charge" numbers are often very-high when I first start driving. Sometimes as high as 500-800+ W/mi. As soon as I start driving, the averages fall dramatically, and I typically net less than 308 W/mi per charge. My "miles driven since charge" trip meters are always less than the speedo range estimate.
- Console Energy App: Using the 30 mile / Average settings, I typically see my energy usage in the 280-310 W/mi range after driving for a bit. The "estimated range" indicator (pointer) typically indicates a few miles MORE range than the speedo range estimate, which was the case for the majority of each leg of my road trip.
CONCLUSIONS/QUESTIONS: I have a few conclusions, but each seems incomplete and raises additional questions. Particularly I'm trying to figure out where energy used for non-locomotive draws (A/C, headlamps, heat, pack thermal management, etc...) is accounted for:
1. Given that the trip meters start with very high energy usage averages after charging, but before driving, I assume they are accounting for some energy usage elsewhere? Yet if this is the case, why do I get less than range-estimated miles if this average is under 308 for the duration of the time since last charge? Does it account for some energy usage, and not other? Or is the artificially high immediate energy usage an artifact of the system "dividing by zero" before the first tenth of a mile is registered on the trip meter?
2. The speedo range estimate always decreases faster than actual miles driven (according to the odometer). Is this accounting for ALL energy used in the system? Was my being able to drive slightly past "0 miles range" because I was below 308 W/mi and therefore the estimate was wrong, or did I dip in to a "battery reserve" Tesla built in to the system?
3. The console energy app would seem to think that my averages would give me more range than my dash does. Which is right? Does the console ignore non-locomotive energy draw?
Any thoughts appreciated.