Power companies always keep spare capacity and will keep their turbines spinning through this unpredictable fall in demand in preparation for when people turn their lights back on again.

电力公司总是保留一些备用发电能力，而在这用电需求突然下降的一个小时中，供电公司的涡轮发电机会继续工作，为一小时后的用电新高峰做准备。

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Sometimes the entrepreneurial spark lights a garage, a spare bedroom, a university media lab or shared office space.

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Since Japan lacks both oil and natural gas, keeping the lights on in Tokyo is going to mean bringing most if not all of that spare capacity back online, and that will require importing more petroleum to fuel the plants.

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