If a solar panel exhibits signs of rust, immediate action is essential to ensure optimal performance and longevity. Identify the cause of rust, 2. Repair or replace if necessary, 4. The most critical point to. If solar photovoltaic panels are rusted, 1. Rust can greatly impact the efficiency and life span of panels. The corrosion within photovoltaic (PV) systems has become a critical challenge to address, significantly affecting the efficiency of solar-to-electric energy conversion, longevity, and economic viability. This topic is particularly relevant for: What Causes Rust on Solar. Some of the most common solar panel issues include rust caused by moisture, microcracks that result from bending, and inner module damage.