Power generation from renewable sources has greatly increased in the last decade. Accordingly, the planning of power system expansions must incorporate the special features of these types of energy sources. Long-term power transmission expansion planning usually does not take these differences among energy sources into account because of the long period considered. However, modelling the special features of renewable sources may influence the optimal transmission plan. In this study, the authors propose a methodology for long-term power transmission expansion planning that incorporates the costs associated with the operation of wind power plants. In particular, the authors model the transmission expansion planning problem as a mixed-integer linear program in which the variability of the wind resource, the impact of wind power operation in the system security and the impact of wind power operation in the reserve market are incorporated. The authors illustrate the methodology using a 34-node version of the main Chilean network.