Over at the Petrozero.org web-site, reader Scott has put his Photoshop skills to work creating a rendering of what the production Chevy Volt might look like. Working from one of the original images of the concept, the shots of the taped up wind tunnel model and what we've been previously told, Scott went to work. You can see the final product as the lower image above which is clearly recognizable as a Volt. Notice that the front axle center line has moved backward relative to the nose of the car and the front door cut line. The nose is now more rounded and less blunt than the concept. This is necessary to clean up the airflow around the front of the car and meet European pedestrian protection standards. The roof line, as expected, is higher and the base of the windshield is further forward with more rake, again for improved aerodynamics. The one area where the final car will likely diverge the most from this rendering is the curved side glass at the top of the doors. This will almost certainly (although I could be wrong) go away. The extra complexity of manufacturing the doors this way and the distorted visibility would likely kill that design element. Instead, judging from the wind tunnel model, the bottom edge of the side glass will probably be slightly lower than shown hear and the doors themselves will probably be solid.

[Source: PetroZero.org, thanks to Scott for the tip]

As part of Wal-Mart's program to double the fuel efficiency of its heavy-duty truck fleet in 10 yeas, not only have they just announced that they're investigating dual-mode, diesel-electric drivetrains, but other cutting edge truck technologies may be on the way as well. The Rocky Mountain Institute, who developed the Hypercar concept, has been working with Wal-Mart to redesign its truck platform with the focus on aerodynamics, tires, transmissions, and auxiliary power systems.

In a bid to reduce wind resistance and drag, the tractor has been redesigned to be significantly more aerodynamic plus the trailer gains side skirts; "wide based" and/or high-efficiency tires, whose reduced rolling resistance improves fuel economy; and the replacement of one regular rear axle with a tag (load-bearing only) axle, which reduces the truck's weight.

I really wonder why it has taken so long to re-visit the aerodynamics of freight trucks - crude though it may be, the photo above is from research Nasa was doing into air flow testing on aerodynamic trucks in 1975. That's 32 years ago and yet really nothing has changed with the trucks you're likely to see on the roads today.

Related:

• Wal-Mart orders diesel-electric hybrid truck prototype from ArvinMeritor
• How long until we get one? A short history of the ultralight RMI Hypercar
• Radical truck designs by Luigi Colani

[Source: Rocky Mountain Institute via Seeking Alpha]