Solar Panel Degradation Calculator
Calculate solar panel efficiency loss and production over time
About this calculator
The Solar Panel Degradation Calculator helps you estimate how your solar panel system's efficiency and energy production will decline over time. Solar panels naturally lose a small percentage of their efficiency each year due to weather exposure, UV radiation, and normal aging. This calculator projects your system's power output and financial returns across its 25-30 year lifespan, enabling you to make informed decisions about solar investments, plan for future energy needs, and understand long-term system performance expectations.
How to use
Enter your solar panel system's initial capacity in kilowatts, current age, and annual degradation rate (typically 0.5-0.8% per year). Input your local solar irradiance and current electricity rates. The calculator will project your system's efficiency loss, annual energy production, and cumulative output over time, showing both current performance and future projections.
Frequently asked questions
What is the typical annual degradation rate for solar panels?
Most modern solar panels degrade at 0.5-0.8% per year, with premium panels often showing lower rates around 0.25-0.5% annually.
How long do solar panels maintain good efficiency?
Solar panels typically maintain 80-90% of their original efficiency after 25 years, with many continuing to produce power beyond 30 years.
What factors affect solar panel degradation rates?
Climate conditions, installation quality, panel technology, UV exposure, temperature cycling, and manufacturing quality all influence how quickly panels degrade over time.