Ca$h for Clunkers; June 2009; Scientific American Earth 3.0; by Stephen D. Solomon; 2 Page(s)

Old cars that foul the air with dirty exhaust are a valuable commodity in Texas. If you own a clunker at least 10 years old and live near a major city like Houston, the state will give you a voucher worth more than the car's value. Drive the car to a dealer, sign a few forms, hand over the voucher—worth up to $3,500—and drive off in a newer vehicle, no soot trailing you down the road.

For the clunker, this swap is the last stop before being plundered for parts and scrap metal. But for low- and middle-income consumers, it's an opportunity to trade up to a newer car they might not otherwise have been able to afford—a cleaner car that is also cheaper to operate because, being much newer, it gets better gas mileage—further benefiting the environment. Texas sent 13,492 jalopies to the scrap heap during the last year in a program financed by auto inspection fees and designed to help the state's urban areas meet clean air standards. California is trying a scrappage program, too, as are Canada and various European countries.