Focusing on harmonic simulation techniques, this chapter introduces a probabilistic approach for harmonic analysis through Monte Carlo simulations. It addresses the challenges of simulating harmonic propagation in power systems with a high penetration of power electronics, to capture the randomness and uncertainties in power system operations. A novel aspect of this chapter is the development of a Norton equivalent model of wind farms for probabilistic harmonic propagation studies. The methodology employs MC simulations and probabilistic distributions. Appropriate ranges and distribution types of model parameters such as harmonic injection phase angles, magnitudes and equivalent impedance are recommended. The validation of this model against real-world measurements proves its applicability in preliminary harmonic simulation studies and its effectiveness in identifying potential harmonic issues in PE-rich networks.