In May 2007, when South African utility Eskom broke ground on Medupi, the country’s first new powerplant since the 1980s, in some cases it was business as usual. The generating station would be coal-fired, sited next to the supplying mine and—with a 4,800-MW rated capacity—immense. Medupi, by far the largest powerplant under construction in Africa, will be one of the largest in the world upon completion. It will account for about 11% of South Africa’s electricity generating capacity. Kusile, another new plant with a commissioning schedule about 18 months behind Medupi’s, has an identical “six-pack configuration,” with six identical 800-MW
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.