The Dept. of Energy on Dec. 21 announced a $1.45-billion loan guarantee for Abengoa Solar Inc.’s Solana project, the world’s largest parabolic trough concentrating solar plant. The 250-MW project near Gila Bend, Ariz., is the first U.S. large-scale solar plant capable of storing energy it generates. Solana would avoid the emissions of 475,000 tons of carbon dioxide per year compared to a natural-gas-burning plant. DOE has guaranteed or conditionally committed to support 16 clean-energy projects totaling nearly $16.5 billion. Together, they will produce over 37 million megawatt-hours. DOE is also supporting the world’s largest wind farm and a 2,200-MW nuclear
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.