How Effective Are Solar Panels

How effective are solar panels? Solar power can be an ideal way for individuals and households to generate free electricity, but how efficiently different types of panels operate varies significantly, and different factors impacting efficiency differ too. This article will answer all your queries on the topic as well as reveal just how efficient US-based panels really are.

Although we can provide an approximate idea of the efficiency of solar panels installed at home, an accurate assessment requires consulting a certified solar installer – something which we can assist you with.

You don’t need to spend hours searching for solar installers in your area. Fill out our online form to get in touch with ESD Solar’s professional solar installers.




Which Types of Solar Panels Are the Most Efficient?

  • Monocrystalline solar panels
  • Polycrystalline solar panels
  • Thin film solar panels

It is important to understand that the efficiency of an individual solar cell does not necessarily reflect the efficiency of a solar panel (or module) as a whole. Solar panel efficiency typically ranges from 15% to 20%. However, in certain cases, solar cell efficiency can reach as high as 42%.

Monocrystalline Solar Panels

Unless stated otherwise, the performance of solar cells is measured under laboratory conditions. While achieving 42% efficiency is remarkable, it is not feasible to apply this standard to residential users.

Thin Film Solar Panels

Thin-film solar panels can be created by covering a substrate with one or more thin layers of photovoltaic material. Thin film panels are flexible and lightweight. However, they are known to degrade faster compared to monocrystalline and polycrystalline panels. This type of panel is produced using a simpler process, resulting in approximately 5% lower efficiency compared to monocrystalline panels. Typically, thin film cells deliver an efficiency of 15-22% for solar panels.

The Efficiency of Solar Panels in Extreme Conditions


Wind can have some positive effects on solar panels as it helps in cooling them. Cooling the panels by 1 degree Celsius can increase efficiency by 0.05%.


Hail testing involves firing artificial hail at speeds between 20 and 30 m/s, which are considered safe for solar cells. According to a report by NREL analyzing 50,000 solar energy system installations from 2009 to 2013, only 0.1% of the systems either underperformed or were damaged by hail. Therefore, extreme hail weather conditions are generally not a problem for solar panels.


A thick layer of snow can render a solar panel unusable. Snow accumulation exceeding 5 cm can cause solar cells to stop functioning, resulting in a 100% reduction in solar panel efficiency. The tilt of solar panels allows for snow to slide off naturally, and it can also be manually removed to restore functionality.

Chemical Residue

Various environmental factors, such as industrial emissions or nearby agricultural activities, can result in the deposition of chemicals on the surface of solar panels over time. This residue can negatively affect the performance of the panels.

UV Degradation

UV-induced degradation can cause the solar cell structure to become brittle and can lead to discoloration or loss of individual solar cells. Exposure to sunlight can also result in the formation of a layer of boron dioxide on the surface, which reduces efficiency by 1-3% within the first 1000 hours.

Damp Heat Testing

Damp heat testing evaluates the performance of solar panels under high humidity and temperature conditions. The effects of this testing on solar panel efficiency were not mentioned in the provided text.


When a silicon coating has not been applied, ice can accumulate on the surface of the solar cells. Ice buildup can reduce solar panel efficiency by 25 to 100%.

It is crucial to consider all factors that may impact solar panel efficiency and to maximize output right from the beginning.

How Effective Are Solar Panels Under Extreme Conditions?

The efficiency testing of solar panels is conducted to ensure that no low-quality panels are sold on the market. Manufacturers must demonstrate that the panels are both durable and efficient. Certification for solar panels in the US market is obtained by successfully passing rigorous testing.

One potential issue that can arise is the degradation of solar cell structures due to exposure to UV radiation, which can lead to brittleness. Another consequence is the discoloration or loss of individual solar cells. Additionally, prolonged exposure to sunlight can result in the formation of a layer of boron dioxide on the panel’s surface, which can reduce efficiency by 1-3% within the first 1000 hours.

Four Key Attributes to Consider When Choosing Solar Panels

  • The cost of solar panels per square meter
  • The entire solar panel module’s efficiency
  • Lifespan for individual solar cells
  • Solar panel aesthetics and style

It is also worth considering the possibility of storing the electricity generated by your solar panels for nighttime use. Homes in the US equipped with solar panels can generate electricity during the day. By installing a solar energy storage system, you can utilize the stored electricity in the evenings and reduce your reliance on the electrical grid.

The insulation resistance of solar panels is determined by the strength of the materials used. Panels made from weaker materials may experience current leakage, particularly around their edges.

The Future of Solar Panel Efficiency

So how effective are solar panels? Looking ahead, it is crucial to consider all factors that can impact solar panel efficiency and strive to maximize output right from the start. This approach will lead to more affordable and efficient solar power modules that are easy to install in homes.

Efficiency testing of solar panels is conducted to ensure that only high-quality panels are available in the market. Manufacturers are required to demonstrate the durability and efficiency of their panels. Certification for solar panels in the US market is obtained by successfully passing rigorous testing.

Solar cells are typically tested in fully automated, state-of-the-art facilities dedicated to solar panel testing. This high testing standard allows for the classification of solar panel efficiency into groups with similar power outputs.

Areas We Serve




Scroll to Top