Previous researchers have made great contributions to the wind energy evaluation. However, the research into the wind energy classification has been scarce, even though this work is closely related to the rationale choice of locations for wind power plants. The traditional wind energy classification schemes consider only partial wind energy factors. Commercial development of wind energy is concerned not only with the characteristics of the wind regime itself, but also a series of factors closely related to environmental risk and cost. In this study, a new wind energy classification scheme that incorporates a comprehensive consideration of wind energy factors, environmental risk factors and cost factors is proposed to rezone the potential offshore wind energy resources worldwide. Comparison of the new and previous wind energy classification shows a good general agreement across large scale of the global oceans, whereas the wind energy of the North Pacific westerly, 30 degrees S and 30 degrees N waters of the global oceans may have been overestimated by the previous schemes. The new scheme highlights regional differences in wind energy classification compared with the previous schemes. By rationally adjusting the weighting coefficients, this scheme has practical value for both macro and micro-scale wind energy classifications. (C) 2018 Elsevier Ltd. All rights reserved.