Oil drilling technology leaps while clean energy stumbles - Article Photos 4/5

FILE - This Tuesday, Aug. 25, 2009 file photo shows capped wells in the foreground as Anadarko Petroleum Corp., uses a walking rig to drill a series of wells on a pad on a Weld County farm near Mead, Colo. In the past, when rigs were finished drilling a well, they had to be disassembled and trucked to the next location, a process that took several days. Now some rigs can “walk” hundreds of feet on hydraulic shoes to the next drilling spot. This reduces drilling costs. (AP Photo/Ed Andrieski, File) ORG XMIT: NYBZ506