In synch with the new vehicle fuel efficiency standards, I strongly recommend that a national maximum speed limit of about 60 mph be implemented ASAP for ALL vehicles. Such a limit would yield IMMEDIATE benefits with EXISTING vehicles including:
- Greater fuel efficiency
- Reduced emissions
- Improved highway safety
Future vehicle technologies and designs would be more easily facilitated, simplified and cost reduced because top speeds affect power sources, gearing, brakes, tires, crash protection features, etc.
Automobiles are most fuel-efficient between 45 and 60 mph. Large trucks lose fuel efficiency over 50 mph. However, 70 mph is the typical maximum auto speed limit (with parts of Texas and Utah having 80 mph).
Congress is unlikely to initiate and pass the needed, common sense legislation in a timely manner. A 60 / 65 mph bill proposed about a year ago by Representative Jackie Speier, et al died in committee when the last Congress closed. With other countries hoping for increased U.S. leadership on climate change and sustainability, non-elected officials with technical backgrounds (like yourself and NASA's Dr. James E. Hansen) must take a strong initiative based on scientific realities!