The bulk of the energy reaching the tires is spent on two things: Drag and tires rolling resistance. Aptera is a marvel of engineering when it comes to the coefficient of Drag. So, most of the energy will theoretically be spent on overcoming tires rolling resistance. I believe Aptera deserves a serious effort devoted to developing specifically designed tires especially that the vehicle is light but most importantly that it is a three wheeler. Regardless of the fact that steering and suspension are kept as is, there may be a favorable improvement. I did not come across much in the literature that applies to such a case.
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I've often wondered if Low Rolling Resistance also equates to longer braking distances.
RR varies with the weight on the tire, & at 2000 pounds or less, Aptera's tires have the RR of only a pretty light 2700Lb car (4 wheels). So there's much less to gain than with a truck or Tesla. Yet there is cost & convenience to lose, as well as traction & wear (although those last 2 are also less important with less weight).
Aptera said they tried at least 10 different standard non-LRR tires & selected the one with the lowest RR. Yes, every little bit counts, BUT there seems to be VERY little to no difference between some standard tires & LRR, with many drivers reporting the exact same range.
Others who report otherwise need to clarify that they have identical diameter, width* & weight, and are driving with the same airspeed (mph + headwind), hills, & ambient/battery temperature, since those last 3 are HUGE factors by comparison to tires. I couldn't even measure a difference between 38psi & 50psi, but that might be because the battery was a bit cooler one week, or I drove 1/2mph faster.
*Not all 195/50-16s have the same overall width OR tread width.
There is a LOT of development behind the conventional tires. Unless some breakthrough technology is introduced, my suggestion to Aptera is, donĀ“t reinvent the wheel. Keep standard tires in our cars please!
Brake pads friction, no matter how minute, has an undesirable accumulated effect. Regenerative braking combined with Magnetic or Electromagnetic brake calipers and the right software once certifiable will probably be a good candidate solution.
For a terrestrial vehicle drag is Aerodynamic (Air Resistance).
Tire Rolling Resistance:
If a vehicle travels in vacuum on a perfectly flat smooth horizontal tarmac, then: All the energy DELIVERED TO THE TIRES to keep the vehicle moving at a certain velocity is that used to overcome "Tire Rolling Resistance";
This is how much rolling resistance is!
By the way, this is ALMOST the case with Aptera which has the coefficient of drag of a Windshield wiper.
It's the opposite of MAGLEV which has zero rolling resistance (since no tires) and spends "all" of the NET energy to overcome drag.
The next level is MAGLEV in vacuum or space travel.
My BEV's OEM tires were LRR, & they were the worst tires I've ever had, with poor traction AND poor wear (usually you get one OR the other).
So once I learned that the car's 100 miles of 75/25 city/highway range was 250% of my US-average daily needs, I didn't bother considering LRRs when replacing them.
I got plain AS tires, 2 sizes wider, with lighter but less aero wheels, totaling about 12% lighter than OEM. I checked carefully & there was absolutely no difference in range. The wheels' lighter weight cancels out BOTH their higher drag AND the tires' higher RR. I tested at std. pressure AND max, with no detectable difference, for OEMs or for the replacements.
Keep in mind that a few mph headwind makes SO much difference that something as small as RR is very hard to detect outside of a lab. I can DOUBLE my power use on the exact same route to my grocery store, just by driving as fast as possible instead of driving sedately. Nathan Andrews says switching to LRR only reduces drag about as much as brake pads normal slight grazing against the disc, like when you jack up a wheel & spin it.
I In my experience with my 2011 Chevy Volt the low RR tires do save energy. However with them I experienced about two to three times the amount of tire problems including blow outs, also the the handling was much worse than what I experienced with a normal tire. The standard all weather tires did result in about 15% less range.
https://technology.nasa.gov/patent/LEW-TOPS-99