This study examines the electrical and thermal performance of carbon fiber prepreg composite laminates for de-icing and anti-icing applications, relevant to wind turbine blades and aircraft wings. Both undamaged and damaged plates with various lay-ups, co-cured on a glass fiber composite sandwich, were analyzed. Various electrode attachment techniques were evaluated, with embedded stainless steel strips proving the most effective for uniform current distribution. Electrical resistance was measured by applying voltage and normalizing results to the effective conductive area. The resistance decreased with increasing temperature, demonstrating semiconductor behavior. Fiber orientation also significantly affected electrical resistance and temperature rise, favouring electrical current flow along the fiber directions. Different repair methods for damaged laminates were considered, revealing that repairing multiple layers in one step yields better results than a multi-step approach. A numerical analysis by means of the finite element method using ANSYS software was carried out to simulate the electrical and thermal performance. The difference between simulations and experiments was consistently within 5 % accuracy, confirming the model's reliability. In all, the findings provide valuable insights towards optimized electrical performance of carbon fiber composites in aerospace and energy applications.