In 2009, the company generated 29% of its revenue from selling steam coal to power plants, and 10% from sales of coking and pulverized coal that feeds the blast furnaces at steel mills and other metallurgical operations.

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Gas turbines, steam turbines, nuclear power plants, high-speed trains, these are the areas he believes Hitachi can still be a world beater, especially in the developing world.

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But Ragnarsson says Iceland's volcanic landscape is a world treasure and should not be criss-crossed with steam pipes and transmission lines or pocked with power plants.

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Geothermal power plants turn hot water into steam or vapor to run a turbine and generate electricity, after which the water is injected back into the underground geothermal reservoir.

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Tellingly, about two-thirds of bids for solar energy contracts last year (by electricity generated) were for photovoltaic projects and only a third were for solar thermal power plants, which deploy vast arrays of mirrors to heat liquids and produce steam to drive an electricity-generating turbine.

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