Electric heavyweights GE Energy, Fairfield, Conn., and Japan’s Mitsubishi Heavy Industries have agreed to work together to develop what they are calling the next generation of steam-turbines for gas-fired combined-cycle plants. In January, the two companies signed a memorandum of understanding to pool their knowledge in order to make the steam turbine technology more efficient. "There are potentials to push the boundaries beyond where we are in terms of efficiencies in operating parameters and start-up capabilities," says Trevor Bailey, general manager of steam products for GE Energy. The memorandum provides "a significant benefit over what we could achieve individually." Bailey
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.