Kannagawa Hydropower Plant, Japan

With the commercial debut of the first of six planned 470-MW turbines in December 2005, the time has come to pay homage the sheer size (2,820 MW) and longevity (13 years and counting) of TEPCO's Kannagawa Hydropower Plant. By the time Unit 2 is commissioned in 2010, and Units 3 through 6 go on-line "in and after 2016," two generations of engineers, technicians, and builders will have worked on the "pure" pumped-storage project since its inception. As if those stats weren't impressive enough, Kannagawa marks the debut of "splitter runners" for pump-turbines. They increase the effective head of the plant to the highest in the world: 2,142 feet, at a flow of 135,000 gallons/second. That's a very large pump-turbine, indeed.