Reliability aspects in wind farms design

Wind park design is not a straightforward task because it involves many heterogeneous aspects to handle in integrated and systemic way. Historically, the reliability issue has often been neglected in favor of economic issue in power systems design. By following the modern tendency of the power system literature, the reliability constraints have to be satisfied a priori, for sake of power system security and safety. For this reason, a rationale procedure is developed in the paper for suitably comparing various alternatives, at the aim of identifying the optimal candidate to be realized. In the work, a specific objective function is proposed in order to select the better wind farm configuration. It is constituted by some terms which basically compare the profits related to the economic trading in the deregulated electric market and the costs due to the investment, operation & management and to system unavailability. This objective function is accurately investigated as a function of the turbines number in order to derive the most convenient alternative, this implying also the optimal choice of the single wind generators size. The ranking coming out from this assessment is then compared with that one which establishes a preferability in terms of expected load not supplied (ELNS). A compromise choice, between the best alternatives provided by the two criteria has finally to be adopted. A simple numerical application is reported in the last part of the paper for testing the validity of the proposed approach.