While the Union of Concerned Scientists say the technology to build a fuel-efficient family vehicle that can meet future emissions standards is already in some of today's vehicles. And the best answers government mandates with lawyers and lobbyists, they say is 35 mpg by 2020?
I would contend that ANY vehicle can be modified to run "bio-fuels" and reduce emissions 50% for $1,000 - 3,000 per vehicle (the same blank check given to hybrids).
Seriously, my car gets a solid 36 mpg and Toyota has been selling a 36 mpg hybrid minivan (Estima) in Japan since 2006. This is the type of vehicle that really should be used more often in the US... http://toyota.jp/estimahybrid/
How can't we do better by 2020?