The NSA is worried that Anonymous could attack the power grid in the next year or two years. The group has mentioned a plan to shut down the internet on March 31, which it refers to as Operation Global Blackout. The power sector is bracing itself for such attacks. It is unlikely that any such attacks would be small and short-lived, but that’s not the point of the worry, as the public is at risk of a similar attack on the power gird. The resulting sense of submission and helplessness is what is most worrying.”]
Source: https://gizmodo.com/nsa-anonymous-could-cause-power-outages-through-cybera-5886805