Wind energy, which accounted for 39% of all new U.S. electric generating capacity last year, could provide 20% of the nation’s electricity by 2030 if growth trends continue for wind power installations, according to a recent study. On the down side, siting, planning and cost allocation issues remain “key barriers” to transmission investment, the study says. Slide Show It may be possible to reach the U.S. government’s goal of producing 20% of the nation’s electricity from wind energy by 2030, but the production goal it is not a shoe-in, says a recent report. To reach the 20% goal, installations would
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.