On the heels of a House panel’s passage of a comprehensive global-warming bill, the Senate Energy and Natural Resources Committee was close to approving a wide-ranging energy bill of its own at ENR press time. The Senate committee package, introduced by panel Chairman Jeff Bingaman (D-N.M.), is similar to the one the House Energy and Commerce Committee cleared on May 21, but there are some key differences. Bingaman’s bill would require 15% of U.S. electricity to come from renewable sources by 2021. The House committee bill has a 20% standard. The Senate committee measure would give the Federal Energy Regulatory
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.