How Much Efficiency Do Solar Panels Lose Per Year

There are three points i want to make.

How much efficiency do solar panels lose per year. These days panels are typically around 17 efficient. Listen to this story photovoltaic pv modules typically come with 20 year warranties that guarantee that the panels will produce at least 80 of the rated power after 20 years of use. By the end of their 25 year useful lifespan they will still be operating at 82 5 a slightly more durable panel with a degradation rate of 0 5 will likely produce around 87 5 as much electricity as. However unless otherwise stated the performance of solar cells is measured under laboratory conditions.

Use the solar panel s warranty to compare output loss over time because that is the only output you are guaranteed. Factors that affect solar panel efficiency solar panels have been consistently increasing in efficiency at about 5 annually since 2010. However solar panel manufacturers are starting to realize that this is too conservative and they are beginning to warranty their panels to more realistic degradation rates. The average efficiency of solar panels falls between the 17 to 19 percent efficiency range.

Over 25 years it is around 20. This is how much of the light energy falling on the panel gets converted into electrical energy. What this means for the end customer is that solar panels over the years become slightly less efficient and will over time produce slightly less electricity. According to a national renewable energy laboratory nrel study premium modern solar panel manufacturers such as panasonic and lg offer panels with degradation rates as low as 0 30 per year.

The solar industry standard is a conservative estimate of 3 in the first year and less than 1 per year after that. In mono crystallineand poly crystalline solar panels the effect is more subtle in the order of around 0 7 power loss per annum. We estimate that solar panels lose about 1 of their production every year. How much do solar panels decrease over time.

The worst degradation rate is 80 a year but as a benchmark you can expect an average degradation rate of 50 a year for any panel. For the above example a 0 8 degradation rate means that in year two your panels will operate at 99 2 percent of their original output. Is that estimate accurat.