Among the energy-saving options, two promising technology switches are the electrification of transportation (electric vehicles can be about four times as energy-efficient as standard fossil-fuel vehicles) and the use of electric-powered heat pumps to deliver winter heating and hot water (heat pumps can be four times as energy-efficient as standard heaters).

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One being tested at Victoria station pumps river water through heat exchangers.

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The tsunami destroyed the diesel generators that provide power to drive the pumps that circulate the water coolant through the reactor that removes decay heat.

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The water is further heated by five solar-powered electrical pumps, to create radiant heat coming up through the wooden floorboards.

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