I finally got information for the Solarworld No.1 solar car .
Professor Eckard Beese, from Bochum University, responsible for the final shape, was kind to provide information.
"Dear Mr. XXXXX
in the Audi wind tunnel, the ready-to-drive vehicle had a cw value of 0.097.
Because we wanted to adjust the geometry as close as possible to the original Morelli contour, which is getting narrower towards the front, the solution offered three wheels, one wheel at the front.
This is not the optimal solution for the handling, but for the aerodynamics.
With two wheels in front, the geometry has to be changed significantly, which makes the aerodynamics worse.
Sincerely yours
Eckard Beese"
It's probably the best Morelli's shape use for final drag coefficient ever made. Aztec solar car had a 0,12 CW, Aptera type 1 (Zen) had a 0,11 (while 2E version had 0,12). The Fusion Machine (4 seats bike) probably have higher than 0,097 due front wheels despite streamlined covers.
Solarworld no.1 also have a lower frontal area, while Aptera large front wheels stream covers probably increased the frontal area significantly. So I presume the difference for CDA between solarworld no.1 and Aptera is even higher.
