Yes, solar does have what is called a degradation rate. However, solar panels are well known for being extremely durable and long-lasting. For example, a Panasonic 330 panel is warrantied to degrade by .26% per year, meaning that at the end of a 25-year period the panels will still produce over 90% of what they did on day one. This is why solar is a great long-term investment that offers savings and peace of mind.