It takes at least 20 milliwatts to keep a mobile phone operating in standby mode, but Nokia hopes that power scavenging might eventually deliver 50 milliwatts, enough to trickle-charge a phone.

保持手机在待机状态下作业至少需要20毫瓦电力，但是诺基亚希望电源收集最终可以提供50毫瓦电力，足够给一部手机缓慢充电。

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It takes at least 20 milliwatts to keep a mobile phone operating in standby mode, but Nokia hopes that power scavenging might eventually deliver 50 milliwatts, enough to trickle-charge a phone.

ECONOMIST: Monitor