SOLAR SYSTEM DEGRADATION OVER TIME

When evaluating whether or not a solar system is a good long-term investment for green-minded homeowners, there are many factors to take into consideration. One such factor is the length of time a solar system can be expected to produce solar energy.

As solar panels are a relatively new technology and have only increased to the level of efficiency necessary to effectively offset traditional energy consumption in the last ten years, it is difficult to conclusively state the true shelf-life of an average solar panel. However, the National Renewable Energy Laboratory (NREL) has conducted comprehensive studies on the life of solar panels and systems which has delivered some promising results.

NREL and other similarly-purposed agencies have conducted many tests in order to determine solar's potential as a green and renewable energy source. Those tests demonstrate that the industry standard manufacturer's warranty of twenty-five years may actually be on the conservative side. The standard monocrystalline and or polycrystalline panel degrades at a rate of .05% per year according to recent studies. It should be noted that the standard solar panel will degrade more quickly during the first few years of its life, mainly the first year of its life. Degradation rates of panels during their first year range from 1-3%. After a panels first few years, degradation will drop to less than 1% depending on the type of panel. Thin-film panels degrade more quickly than their crystalline silicon counterparts who are closer to a .5% rate of degradation per year.

If a 1% rate of degradation per year seems high, there are some other factors to keep in mind as well. Assuming that a solar panel begins its life performing at 100%, most solar panels on the market today are guaranteed by their manufacturers to produce no less that 80% of rated power after 25 years. The current industry standard also shows that modern panels perform at around 90% of rated power after 10 years. Modern panels have been designed for use in remote places and to withstand conditions in space. Modern technology continues to improve the solar power producing efficiency of solar panels. All of this spells good news for current panels which are encased in metal and glass frames designed to withstand hurricane winds, rain, hail and other weather conditions.
Solar panels are not the only component of today's solar system. In order to use the power generated by modern solar panels, a solar inverter or inverters must be attached to panels in order to convert DC to AC current. Solar inverters have a 10 or more year lifespan due to their sensitive electronic nature, high internal temperatures, high ambient temperatures and a few other important factors.

Like a car, monitoring a system's performance combined with proper care and maintenance can increase the lifespan of today's solar system. It is important to clean panels from time to time in order to keep them efficiently producing solar energy. Imagine a windshield caked with a year's worth of dirt and dust and how well someone would be able to see out of it. Solar panels are somewhat designed to be self-cleaning twenty five years is an awfully long time to go without a wipe-down and an oil change.