Various groups of scientists around the world have been working on it for years, but the problem has mainly been the efficiency, or rather the inefficiency with which power is transfered over the air.

多年来世界各地的各色科学家小组一直致力于无线供电研究，效率一直是主要的问题，更确切的说是电力在空气中传输的低效率问题，绝大部分电力在到达目的地之前就损失了。

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But it still concentrated mainly on reporting the views of pro-government groups.

BBC: NEWS | Middle East | Iran media lean to the right