Highway speed limits across much of the country are 70 – 75mph. If you have the $29,800 Aptera with a driving range of 400 miles can you actually get 400 miles of driving range at these highway speeds?
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I believe air resistance increases by the square of the velocity*, but that's still huge. For example in my own BEV, 70 mph gives 25% less range than 55.
They say that the 3rd motor will make a difference of "a few %". Cold weather makes much more difference, temporarily reducing battery capacity, as well as increasing air density.
*EDIT: Okay air DRAG increases by the square of velocity but apparently the POWER required does increase by the cube (about halfway down Bojan's link). I suppose with those formulas someone could approximate the range at 70-75mph based on the known range numbers at 48mph avg.
That link does have at least one error: "... half gets lost in heating up the brakes.". Even a 6-yr-old eGolf uses no friction brakes in normal driving. I believe most Teslas are similar, & even my 8-yr-old 500e can do that if I'm careful/lucky to keep it above 6mph.
No, I don't think so. The ranges are based on the EPA Highway cycle with an average speed of around 48 mph and a peak of 67 mph. There will be a lot more testing before we have a solid number, but it appears that you might get more like 270 miles at these speeds. Cold weather will hurt the range, and high altitude will help. Remember that although the Cd is extraordinarily good, air resistance increases by the cube of the velocity. Whether you have 2 or three wheel motors will also make a difference. In a few months we will have a much better read on this.*Edit: Thanks to Kiteboarder for the correction. I should have said the power required increases by the cube of the velocity rather than the air resistance. I was sloppy. However, I don't think my conclusion regarding range reduction is far off.
Efficiency – a calculation
http://aptera.nu/?p=67
I believe air resistance increases by the square of the velocity*, but that's still huge. For example in my own BEV, 70 mph gives 25% less range than 55.
They say that the 3rd motor will make a difference of "a few %". Cold weather makes much more difference, temporarily reducing battery capacity, as well as increasing air density.
*EDIT: Okay air DRAG increases by the square of velocity but apparently the POWER required does increase by the cube (about halfway down Bojan's link). I suppose with those formulas someone could approximate the range at 70-75mph based on the known range numbers at 48mph avg.
That link does have at least one error: "... half gets lost in heating up the brakes.". Even a 6-yr-old eGolf uses no friction brakes in normal driving. I believe most Teslas are similar, & even my 8-yr-old 500e can do that if I'm careful/lucky to keep it above 6mph.
No, I don't think so. The ranges are based on the EPA Highway cycle with an average speed of around 48 mph and a peak of 67 mph. There will be a lot more testing before we have a solid number, but it appears that you might get more like 270 miles at these speeds. Cold weather will hurt the range, and high altitude will help. Remember that although the Cd is extraordinarily good, air resistance increases by the cube of the velocity. Whether you have 2 or three wheel motors will also make a difference. In a few months we will have a much better read on this. *Edit: Thanks to Kiteboarder for the correction. I should have said the power required increases by the cube of the velocity rather than the air resistance. I was sloppy. However, I don't think my conclusion regarding range reduction is far off.