Droid 的电池可以让你用上一天，跟 iPhone 一样，但是，不同的是你可以带一块备份电池。

The Droid’s battery gets you through one day, just like the iPhone’s, but you can carry a spare.

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太阳能电池仍将作为备份电源。

Solar cells will still be used for backup power, however.

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较大型的单元大多采用电池、飞轮、柴油电机或三者的组合作为备份电源。

Most of the larger units use batteries, flywheels, diesel generators, or a combination of the three, acting as a backup power source during power quality or utility disturbances.

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