You get a rebate of $4500 from the US government if you turn in your old low mileage vehicle for compaction and purchase a new high mileage vehicle. It is being touted by almost everyone as a smart idea. A green initiative.
I have my misgivings about the whole plan.
(1) Since a clunker has a low mileage, the high cost of refueling the thing acts as a disincentive from driving long distances.
(2) Since the new vehicle has high mileage, (and is in all probability much safer than the clunker in question) will that not increase the amount of joy rides? More vacations to Yellowstone from Texas? Since the economic need for car-pooling to work reduces, will people not feel tempted to just go it alone and keep their routines flexible?
(3) And here's the most important issue. If you were using your clunker, you would not be purchasing a new vehicle. Building and transporting a new vehicle constitutes ~ 30% of its lifetime energy costs. So, by tempting people to get rid of their clunkers and replace them with high mileage Prius-types, you are inadvertently creating a spike in greenhouse gas emissions.
I intend to elaborate on point 3 a little while later, with actual figures regarding the energy consumption (carbon footprint, if you will) of manufacture of vehicle.
Cash for clunkers is far from green. It is a stimulus program aimed at rewarding bad behavior, little else. As a matter of fact, the only way legislation can be green is if it mandates steep fuel taxes / energy costs. (I am pessimistic about cap-n-trade.It might have a tough time getting passed in the US senate, what with climate change denial being quite the rage in republican circles these days.).