Solar Panel Degradation Over Time

Understanding these elements is key when selecting solar panels for your home or business.

Solar panel degradation over time.

For most tier 1 solar panels the degradation rate is 30 meaning that each year the panels performance is reduced by 30. For example solarcity the largest residential solar installer in the u s guarantees that its panel efficiency won t degrade below an 80 efficiency rating over a 20 year power purchase. It does because yearly degradation compounds over time. Quantification of power decline over time also known as degradation rate is essential to all stakeholders utility companies integrators investors and researchers alike.

At the other extreme panels in desert climates exhibited large decreases in production over time close to 1 per year mainly due to high levels of uv exposure. In the years since this 2012 study was conducted more efficient technologies have been developed and many newer panels have just a 0 5 percent yearly decline in energy. Does that really matter. Over 25 years that adds up to a total of 6 96 meaning your panels will operate at 93 04 of their original capacity in 2045.

However a study conducted by the national renewable energy laboratory nrel shows a more accurate picture of solar panel degradation. That s backed up by the solar panel manufacturer s warranty which guarantees 90 production in the first ten years and 80 by year 25 or 30. There are lots of different reasons why they degrade and why they fail kurtz said module manufacturers are looking into every piece of the solar panel puzzle all the way down to the encapsulants and adhesion materials to try to slow degradation rates. Solar panel degradation and failure is not a clear cut situation kurtz said.

On average solar panels degrade at a rate of 1 each year. Below is a comparison of the output of solar power systems over a 50 year period with degradation rates of 0 25 sunpower s expected average 0 4 an excellent rate of degradation 0 8 the mean average found in some studies and 1 the old standard. Financially degradation of a pv module or system is equally important because a higher degradation rate.