From MIT News:
How much gasoline would the nation save in the year 2035 if lightweight hybrid and plug-in hybrid vehicles dominated the marketplace? More than 68 billion gallons, or about half the fuel currently used each year by today's vehicles.
Such detailed analyses in a new MIT report published this month conclude that over the next 25 years, the fuel consumption of new vehicles could be reduced by 30-50 percent and total U.S. fuel use for vehicles could be cut to year 2000 levels, with greenhouse gas emissions cut by almost as much. But it will be challenging to meet those demands....
...For the near term (up to 15 years), we should increase our efforts to improve light-duty vehicle engines and transmissions, but all improvements must go toward increasing fuel efficiency rather than making cars bigger and faster. Also critical is reducing vehicle weight and size.
For the mid- and long-term (15-30 years, and more than 30 years), we should ramp up work on radically different technologies such as plug-in hybrids and hydrogen fuel-cell vehicles....MORE
Executive Summary (PDF, 430 KB)
Full Report (PDF, 2.8 MB)
Press Release (link)
HT: Next Big Future