How Material Affects Solar Panel Efficiency | Simply Solar

Evaluating Different Solar Panels

For homeowners who are considering a change to solar power, one of the main concerns is the efficiency of the solar panel itself. A panel’s efficiency refers to its ability to convert the sun’s rays into usable power. It is an important metric because more efficient panels can generate more electricity, often take up less space, and provide greater value over the life of the panel.
First, it is necessary to distinguish among the three main types of solar panels: monocrystalline, polycrystalline, and thin film.


Although monocrystalline solar panels are typically the most expensive type, they also provide the greatest level of efficiency. As a result, consumers will benefit, the most, financially in the long run with this panel. There is a greater upfront cost, but you can expect to recover your investment more quickly due to lower monthly energy rates.
Currently, monocrystalline panels provide efficiency ratings of over 20 percent. Given their increased efficiency, they also provide the most energy while taking up the least space. This makes them a great option for homeowners in small homes or with more challenging installation needs. Monocrystalline panels also last the longest, most often coming with a 25-year warranty.


Polycrystalline panels are mass-produced and therefore are a more affordable option. They are the most common type of solar panel and are best used by homeowners with flat roofs and few obstructions.
The efficiency rating for polycrystalline panels is lower than monocrystalline, but these panels still generate enough electricity to significantly impact your energy bill. Energy ratings typically fall between 15 and 20 percent, which is strong for homeowners without extensive energy needs. The efficiency falls a bit more with polycrystalline panels because they are typically connected to a string inverter; however, this also helps keep the initial costs low.
Overall, polycrystalline panels are a good option for everyday home use. They manage a solid efficiency rating and are typically installed with a 20-year warranty.

Thin Film

Thin film panels are the easiest to produce, the slimmest, and the least expensive. However, they also rank lowest in regards to efficiency. Typically coming in around 10%, thin film panels need to be extended over large spaces to generate the power of a smaller monocrystalline or polycrystalline panel.
They also deteriorate more quickly over time, with a typical warranty of 15-20 years. If you have a large space to install thin film panels, they are a good option (especially if you want to limit your initial investment). However, they are the weakest option of the three.

Weather Considerations

Solar panel efficiency is determined under optimal conditions; and is often tested in maximum sunlight and favorable weather conditions. So, what happens when the weather is poor – and how does that affect efficiency?

Fortunately, manufacturers also test solar panels under adverse weather conditions to determine both the efficiency and longevity of the panel. For example, wind damage is one of the most common factors when determining panel longevity. Solar panels are put through aggressive wind tunnel testing so that they can withstand most gusts.

Panels have also been tested in snow and ice. Hail testing shows that solar panels can withstand hail speeds up to 30 m/s without accumulating damage. Ice can be more damaging (particularly to panel efficiency), but not in the form of hail. Ice build-up can decrease solar panel efficiency by 25%, and thick ice cover can decrease efficiency all the way to 100%. Similarly, a heavy layer of snow can restrict panel efficiency up to 100%. In cold weather conditions, regular maintenance is recommended to maximize panel efficiency and longevity.

Selecting Panels

After determining your panel type (monocrystalline, polycrystalline, or thin film), you should evaluate solar panels by brand. Although most panels fall within similar efficiency ranges, there are some that are stronger than others. 

Solar Panels in the Future

One of the most exciting aspects of solar panels is that the technology is continually improving. Efficiency ratings from as recently as 2016 have already been surpassed by today’s models. As technology increases, panel efficiency will continue to improve as well. This is good news for consumers, as it means that prices will likely fall, and high-quality solar panels will become available to all consumers.