How Much Efficiency Do Solar Panels Lose

For many panels this is given as 2 to 3 in the first year and then 0 7 a year after that but it can be as low as 0 25 a year for some sunpower panels.

How much efficiency do solar panels lose. Since the use life of a solar system is 20 to 25 years think how the car windows on your car would look if you only hose it off every six months. As the temperature of the solar panel increases its output current increases exponentially while the voltage output is reduced linearly. What is known is that sodium enrichment occurs between the chemicals used on the surface of the solar cell and the glass in certain circumstances causing a leakage of current between the cells and the solar panel frame. Understand that solar panel manufacturers try to avoid the subject as they do not want to make potential buyers aware of the problem.

The great thing is that most solar companies will back up their products with a 25 year warranty or efficiency guarantee meaning that this isn t just a sales pitch to get you on the hook. Photovoltaic modules are tested at a temperature of 25 degrees c stc about 77 degrees f and depending on their installed location heat can reduce output efficiency by 10 25. Interesting that the solar companies tell you that the degradation percentages are 1 per year but in recent studies their findings are closer to 4 and 5. Factors that affect solar panel efficiency solar panels have been consistently increasing in efficiency at about 5 annually since 2010.

The amount of loss can range from a few percent to 50 or more. The highest efficiency solar panels on the market today can reach almost 23 percent efficiency. Do the math a 4 to 5 loss per year in 5 years you ve lost 20 25. Tests by the german fraunhofer institute showed that solar panels which are susceptible can lose more than 30 of their rated power through this effect and as much as 90 in extreme cases.

These days panels are typically around 17 efficient. Solar panels lose efficiency over time so they ll probably be down to about 80 of their original efficiency once they reach a quarter of a century.