The thermal power stations require natural gas, oil and coal to operate, all of which have been rising in price in recent times.

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As a result utility providers have had to turn to thermal power stations which require oil to operate, resulting in a rise in demand.

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This was after the leak at the Fukushima nuclear plant resulted in other nuclear plants being shut, forcing it to rely on traditional thermal power stations to produce electricity.

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There are many nontrivial ancillary challenges too, especially the secondary procedure of actually getting the energy out of the reactor into a useful form, i.e. heat to drive steam-turbines as with all other kinds of thermal power stations, to generate electricity.

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The earthquake and tsunami last year resulted in 15 of its 17 nuclear plants being closed, forcing Tepco to turn to thermal stations for power generation.

BBC: Tepco raises electricity prices for corporate clients

But as its nuclear power stations have been shut, the country's electricity providers have been relying more heavily on thermal power plants to produce electricity.

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