Impact of wind penetration level on optimum transmission planning

In this study, impact of wind power generation penetration level on transmission expansion planning (TEP) problem is discussed. Main focus is to address the following contradiction: wind power generation contributes to TEP problem by delaying the necessary transmission enforcements due to local demand growth. On the other hand, if the installed capacity of wind power plants is much higher than load growth rate of the region, then backdating of transmission enforcement might be necessary. A TEP algorithm, which minimizes summation of transmission investment cost and the cost that appears due to limitation of wind power generation in case of transmission line constraints, is proposed. The proposed planning approach is performed on a simple numerical example. Main conclusion is that, if the difference between the penetration level of wind power generation and local load in any year along the planning horizon is smaller than the steady-state thermal capacity rating of the existing transmission lines, this will result in transmission enforcement delay. Otherwise, there will be risk of congestion which might necessitate transmission enforcement, and therefore, needs optimum transmission planning analysis.