Some Democrats, are also concerned that keeping cash-for-clunkers going means breaking into the clean-energy piggy bank. 
The House proposal calls for grabbing $2 billion from the renewable-energy loan program to keep cash-for-clunkers funded.
In any event, the environmental merits of the program are clearly in the eye of the beholder. Ford Motor Co. will report its first monthly sales increase in two years thanks to the program-and the cars that are moving off the lots are fuel-efficient Focus. “On both counts, it’s going to be a home run," Ford sales analyst George Pipas told The Wall Street Journal.
But an analysis of the real impact of the clunkers program on U.S. oil consumption paints a much more modest picture:
Even if extended, the program will shave U.S. oil consumption by about 0.05%, or roughly 5,000 barrels a day out of U.S. daily consumption of 9 million barrels.
Also: Clunkers program could drive used car prices up
Hundreds of thousands of "clunkers" headed for scrappers may cause already rising prices for used cars to head even higher, dealers and market analysts warn.The popular cash-for-clunkers program, extended by Congress last week with $2 billion more in federal incentives, requires that all the old fuel guzzlers traded in are scrapped — not resold. That means up to 750,000 vehicles will never find their way into the hands of another owner. Many are at the end of their useful lives, but others, with years of life left in them, normally would be resold.
"Those are the cars that lower-income families need," says Geoff Smartt, owner of Smartt Cars in Caldwell, Idaho.