I've been trying to calculate the range, efficiency and consumption of my Tesla Model Y RWD in real world conditions. Tesla's own 455km WLTP score is wildly inaccurate and disproved by almost all owners. Reading forums, people had wildly different thoughts and anecdotal evidence about how much range they were getting, and their efficiency. In summary, there's a lot of confusion.
However, my guiding principle for calculating range is that there should be no compromise or expense spared during a drive. The real-world range is when you've got passengers, cargo, air-con, spotify, occasionally overtaking of slower vehicles, and some winds too - basically everything that Tesla removes from their range scores.
I'm all about data, so to settle this debate, I've been data-logging my Model Y for the last 3000+kms, across every journey, from longer (200km+) road-trips, to commutes around the city of Auckland. I used Teslamate, an open source Tesla data-logger.
For experiment clarity, almost all of my drives had:
- A driver (obviously) and one passenger on longer trips.
- Air conditioning is always on
- Aftermarket turbine wheel covers
- Driving like a normal ICE car (so like a madman)
- Rapid acceleration and overtakes as appropriate
- Autopilot is on during most state highway drives.
My conclusion? There genuinely is a lot of variance based on external weather, roads, traffic, and driving style.
Longer trips: Using Rotorua to Auckland (225km) as an example (full data below) the car went from 100% - 38% on 159Wh/km, autopilot on the entire Waikato Expressway averaging 110kmph. On other data-logged journeys across the North Island, its been between 158-164Wh/km.
Based on these numbers, the car currently has a 58kwh battery, and a usable range of about 350-360km on longer road trips assuming all else remains constant. The battery capacity correlates with what others are finding online, and the range seems about right too from hearsay, so it passes the sensibility check.
I also ran the numbers across all my urban journeys and commutes, that typically range from 1-15km. The biggest factor here was actually ambient temperature. The car averages 400km at 25 deg. celcius, and about 364km at 15 deg. celcius.
Practically, the urban range is of no interest to me, especially if there is home charging available, as you can fit charging around when the car is at home. The practical range to me is the longer trip range, which is about 350-360km.
This too is misleading and faces the same problem all other cars do - since if you're intending to use up the entire 350km or so, you'd depend on arriving at your destination with charging capability, or a supercharger/fast charger at the end that is ready and capable. If you were on a longer trip, you'd then need to factor the distance to the nearest charger, which is always the charger before you hit your range limit. Suppose the next two chargers are charger A at 250km and charger B at 400km away respectively, then your practical range is just 250km as you can't reach charger B and must stop to charge at charger A. ICE cars also face the same problem, but far less frequently, given how many fuel stations exist.