Thursday, March 10, 2005

Gas Guzzling Hybrids

It's one thing to provide actual efficiency improvements; it's another to provide a band-aid when a tourniquet is needed. Such is the case with this MIT Technology Review article about changes in hybrid SUV drivetrains. The GM-Daimler transmission featured adds a new dimension to the vehicle's operation by applying torque through a conventional gearbox at highway speeds. The overall system is more efficient than current engineering practice, but the difference between a 15 MPG vehicle and a 20 MPG vehicle is negligible. What's needed are 40 MPG vehicles, but those don't come without other kinds of compromises.