French energy company GDF Suez has won two long-term energy-supply contracts worth $600 million for Peruvian powerplants. The company, through its subsidiary Enersur SA, will construct the 112-MW Quitarasca I hydroelectric plant in the northern highlands and upgrade the existing ChilcaUno thermal powerplant from 270 MW to 800 MW. The contracts, signed on April 14, run from 2013 until 2025.
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.