Energy (49 images)

Wind turbines spin as the sun goes down in Manjil, Roodbar 140 miles (233 kilometers) northwest of Tehran, Iran on September 2, 2006. A day after the U.N. deadline for Iran to suspend its uranium enrichment activities under its nuclear program, global oil markets appear to be cautiously optimistic about future prospects.(UPI Photo/Mohammad Kheirkhah)

A women rides her bike past a new construction project in the fast growing central business district in downtown Beijing, China on June 08, 2008. (UPI Photo/Stephen Shaver)

Iranians wait in line for gasoline in Tehran on June 27, 2007. Iran, the world's second-largest oil exporter, will begin gasoline rationing for private vehicles yesterday to rein in consumption and cut expensive gas imports. Iranians set fire to a dozen gas stations in the capital early Wednesday and smashed windows, angered by the sudden start of fuel rationing, a step that threatens to further increase the unpopularity of hard-line President Mahmoud Ahmadinejad. (UPI Photo/Mohammad Kheirkhah)

A plug is seen connected into a Toyota Prius plug-in hybrid at a demonstration on new energy technologies aimed at improving Americas energy efficiency, on Capitol Hill in Washington on June 20, 2007. Plug-in hybrid technology uses both current hybrid technology along with a plug-in rechargeable lithium battery. (UPI Photo/Kevin Dietsch)