[lazyjones]

> Can we get that below 10 for regular highway driving, say at 130km/h?

Probably not with normal-sized cars.

For the Model 3, the theoretical minimum is 13.8 kW. This increases linearly with drag coefficient and area (as seen from the front). You would have to build a significantly smaller (flatter, narrower) car and improve the drag coefficient (0.2 has been achieved) to get there.

Here's a calculator in German (sorry) for experiments: http://spare-benzin.de/Fahrphysik/Luftwiderstand/Luftwiderst...