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The energy of a digraph D with eigenvalues z 1 , z 2 ,. .. , zn is defined as E(D) = n ∑ j=1 |ℜz j |, where ℜz j is the real part of the complex number z j. In this paper, we characterize some positive reals that cannot be the energy of a digraph. We also obtain a sharp lower bound for the energy of strongly connected digraphs.