High mpg on short drives is possible, but not in way that you can entirely control or predict for each drive. On the same 'short' <5 mile route, I've gotten as high as 85 mpg when factors are 'perfect' and as low as 15 mpg when factors aren't perfect (e.g. cold weather, ICE runs). So even if you keep your drives to 3 mile radius each, you'll see varying mpg results because of factors listed below and how a hybrid responds to optimize energy.
When in EV mode, the display shows '199.99 mpg' and any use of the ICE lowers mpg from there. Getting 199.99 mpg on a short drives COULD happen if the following types of factors align perfectly each time:
- high starting level of HV battery (supports EV for longer time/distance)
- warm weather conditions (minimizes ICE turning on)
- low throttle demand (low speeds and no hills)
...BUT since these factors will vary by drive (especially starting battery level), you'll see different mpg results even when repeating the same short drive.
Let's say your first 0.75 mi drive to the grocery store is in perfect conditions: full battery, warm weather, low speed/throttle, easy terrain... and you get a 'perfect' 199.99 mpg while in EV for the full drive.
- When you end that first drive, battery level will be lower (since consumed in EV mode during preceding drive). This in turn leaves your starting battery level lower for the next drive.
- Since starting battery level is now lower, you won't be able to travel as far on battery alone for your next drive, and the car's hybrid programming will engage to re-build battery level (especially if at/below ~3 bars).
- To re-build battery level, the ICE will need to engage (reducing mpg) OR you'd need 'free' charging from a downhill descent (unlikely).
...NET unless you can start at the same battery level for each drive, mpg results will vary at the end of each drive even if other factors remain the same (temperature, route).