They could be doing so much more. For a typical car reducing vehicle mass directly reduces kinetic energy, rolling resistance, and aerodynamic drag (via smaller frontal area). And I think if a stalled wing has a much better drag coefficient than a car then this is something that could easily be improved too.
Typical Drag Coefficients
I could say the same thing about city buses too. They could be doing so much more. This is a model of a Superbus. It achieves all the goals of low weight, low drag coefficient, low frontal area, regenerative braking, high engine efficiency, and the appearance of luxury. Every city should have a fleet of these bad boys!
Source: http://www.economist.com/science/tq/displayStory.cfm?story_id=7904103
Compare the Superbus above with the reality below. What a sorry excuse for moderization. The newest fleet cost upwards of a $billion dollars. And they still try to pass 40 people through a single door at the front. It's a nightmare for passengers.
Space/Science » in reply to Update on advanced auto tech
Hybrid car chassis are probably still made of steel