For a typical turbine, 20% of the downtime is due to gearbox failures, and an average gearbox failure takes about 256 hours to repair.

一个典型的风力发电机，20%的停车时间是由于变速箱的故障引起的，而平均每个变速箱的故障修理时间大概是256小时。

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On average, the downtime fell to 1.50 hours per user per year from 5.40 hours.

WSJ: The Sun Shines on 'The Cloud'

Industry analyst firms like Gartner, IDC, Aberdeen and others publish estimates of what an hour of downtime will cost the average company, and how many hours of downtime per year they are likely to experience.

FORBES: All I Want For Christmas Is...System Uptime