Please add the tire used with each rim as that is the critical factor not the rim diameter.
Tire selection is certainly very important but is not a single "critical factor".
Rolling resistance is primarily caused by the bending, compression and shearing of the tire tread. To a lesser extent the sidewall bending is also a contributor to energy dissipation. Each manufacturer optimizes their tires for different characteristics and using a different tire WILL change the energy consumption. Heck, even changing to a new version of the SAME tire will change the rolling resistance as a new tire will have different characteristics than a worn tire. It also not safe to say that the same size and model of tire will perform the same. An example is the T0-spec (Tesla spec) Michelin Pilot Sport 4S tires that are original equipment on the 20" Model 3 wheels. The tread pattern and width is different than the non-T0-spec PS4S tires of the same 235/35R20 size. Beyond the tire itself, changing the inflation pressure as well as the toe alignment will also change the rolling resistance of the tires. Temperature and road surface roughness also have an effect on rolling resistance. An example here is that a tire should be warmed up for at least 20 minutes before taking precise energy consumption data, as the rolling resistance can be over 15% higher in the first few minutes when the tire is cold. (Yes, cold tires are also a contribution to winter range woes.)
Most people do think of only the wheels as affecting the range, but the characteristics of the tire are a significant contribution. As I said in the first post, "using different tires will affect these results." But rolling resistance is, in simple terms, a linear function of speed. That is the energy needed to overcome rolling resistance grows as a function of speed. Aerodynamic drag does not. Energy used to overcome drag grows as a squared function of speed. This means that when doubling the speed, the energy required grows by a factor of four. At highway speeds in the Model Y, total aerodynamic drag is about three times the tire's rolling resistance and the wheel design plays a large role in the total vehicle drag. For a low Cd car like the Model Y, wheel aero drag could be 25% of the total drag.
Tesla has been paying particular attention to optimizing their wheel designs to reduce aerodynamic drag. The key characteristic to reduce wheel drag losses is to increase the flat area near the outer edge of the wheel and to reduce the open area of the wheel. You see these artifacts in the various Model Y wheel designs. They all have relatively little visibility to the wheel interior. Basically, you can't see the brake rotor very easily. They also have a lot of surface area near the wheel rim. Larger diameter wheels are particularly challenging aerodynamically and you can see that the Uberturbines and Induction wheels have a lot of flat area near the rim to reduce drag. The Gemini caps have minimal porting and are obviously optimized to reduce aero drag. The small gaps between spokes reduces the pumping losses when the high pressure air in the wheel well wants to pass through the wheel. Having a completely closed wheel compromises brake cooling so they have to allow some air to pass through.
All of this is to say that both the wheel design and tire design need to be optimized to reduce the energy consumption. Tesla, in conjunction with tire manufacturers, appear to be using relatively low rolling resistance tires. Likewise, they have worked hard to develop low drag wheels.
For the Model 3, there's a 10% difference in highway range between the 18" Aero and the 19" Sport wheel/tires. Highway testing has shown that just removing the aero cap, and leaving the Aero skeleton wheel exposed, results in a 4% loss by itself. On the Model Y, the fact that the 21" wheels/tires are only 14% worse than the 19" wheels/tires is a testament to the effort expended to optimize their design, but the negative effects of the performance-oriented tire tread and compound along with the aerodynamic losses from the larger diameter wheels cannot be avoided.
