Today, there is a vast range of the best portable solar panels employ flexible solar cell technology. Given that they seem so much more useful than rigid solar panels, why aren’t they more popular? As it turns out, there are a number of downsides to flexible solar panels, which has kept their market share relatively small.
What’s so bad about flexible solar panels?
Okay, so flexible panels aren’t bad, but they do have some issues. This has kept many people from buying flexible panels despite the lower cost (check out the cost implications of solar panels), lighter weight, and versatility. Most find that it’s a better investment to pay more for rigid panels unless flexibility is a necessity. So what’s so bad about flexible solar panels anyway? Let’s find out!
They’re not as efficient
Compared to rigid panels, flexible solar panels simply aren’t as efficient. While rigid crystalline panels have efficiencies between 16% and 23%, average efficiencies for flexible solar panels fall between 10% and 17%. This is partially because the thin semiconductor film in flexible panels has less material to react with the sunlight. It’s also that the semiconductor material used in flexible panels is less efficient overall when compared to the crystalline silicon in rigid panels. Explore our article to learn about the effectiveness of polar power cells.
Solution
The best solution is to buy the highest quality panels. The best flexible panels far outperform the lowest grade of rigid panels, so your better off paying more for high quality, especially if the flexibility is a necessity. Another solution, if you have the space, is to simply add more panels to make up for the lack of efficiency. Since flexible panels weigh less, you won’t be putting as much stress on your roof compared to an array of rigid panels. If you don’t need the panels right now, you can also wait a few years. Research is being done on flexible panels that match the efficiency of rigid panels, and from what it looks like, they may not be too far off.
They’re easily damaged
Flexible panels can take being bent and flexed, which is part of their appeal. But too much bending and flexing can actually cause the solar cells to crack. If you have flexible solar panels on the roof of your house, truck, or RV, the plastic can get scratched by branches and trees, which can possibly damage the solar cells as well. One bad hit is all it takes to crack a solar cell, and cracked cells lower efficiency. Rigid panels have a glass covering, which offers more protection from the elements.
Solution
The solution to this is simple. Take care of your panels! Don’t bend or fold your panels more than you need to if you want your panel to last. While solar panels are meant to take a beating, the semiconductor material and electronics inside the panels are still quite sensitive. If installed on a vehicle, drive carefully in places where there are low-hanging branches. Do not walk or stand on the solar panels either. Since they are flat, they can easily blend in on your roof, so make sure to watch your step.
They don’t last as long
The shelf life on flexible panels isn’t as long as their rigid counterparts. Where rigid panels can last anywhere from 25 to 40 years, flexible panels might be functional for just 15 to 25 years. They don’t have a very high efficiency to begin with, so when their power output starts to drop, they aren’t going to be useful for much longer. This also has to do with durability. Since flexible solar panels are often used in recreational settings, they’re more likely to get damaged, which lowers the shelf life. Read our article to see the expected life expectancy of solar panels.
Solution
The easiest way to sustain the longevity of your panels is to learn how to maintain your panels. Keep them free of dirt and dust, and make sure not to damage them while handling. Again, don’t walk or stand on the panels, and take care when driving in woody areas. Any microcracks in the plastic will allow dirt and dust to get inside, ruining the panel and lowering the shelf life. Cracks in the solar cells will cause lower power output, which will also weigh down on your shelf life. Another thing you can do is buy high-quality panels. High-end flexible panels will last as long as some rigid panels.
Shorter Warranties
Since they damage easily and have shorter lifespans, flexible panels usually have shorter warranties than rigid panels. Just like how bad drivers pay more for car insurance, solar companies are less willing to take on the risk of insuring flexible panels. Warranties for rigid panels are usually around 25 years, while flexible panels might only have 15 to 20 year warranties.
Solution
Take care of your solar panels! If you keep up on maintenance, your panels will function long after the warranty expires. You might only have a 15 year warranty, but your panel could continue to provide adequate power for another 10 years. It’s also important to note that since high quality panels last longer, they tend to have longer warranties.
Some are toxic
Some panels are made with toxic materials. Specifically, CdTe and CIGS panels, both of which can be manufactured as flexible panels. CdTe contains cadmium, which is highly toxic and carcinogenic. While the workers who manufacture CdTe panels face the most risk, the customer may be at risk as well. Breaking the panel and being exposed to the semiconductor material can potentially cause adverse health effects. This also applies to CIGS solar cells, but they are much less toxic. Similarly, the panels are bad for the environment. If they’re improperly disposed of, the toxic chemicals can leech into the soil and water supply. Rigid panels and some flexible panels use silicon for the semiconductor material, which is inert and poses little threat to people, wildlife, or the environment. Still, all solar panels are treated as hazardous waste when disposed of.
Solution
Cadmium telluride (CdTe) and copper indium gallium selenium (CIGS) are some of the more efficient types of flexible panels, so some may opt to buy these types over flexible silicon panels. If you’re interested in either of these types, then it’s imperative that you’re aware of the risks. Taking good care of the panels is a must. Fortunately, you have to really do some serious damage to the panel in order to be exposed to the toxic chemicals, so it’s unlikely that you’ll encounter any issues. It’s also important to make sure that you treat them as hazardous waste when you dispose of them. Though this is the rule for all solar panels, it’s especially true for CdTe and CIGS panels. There are solar panel recycling programs in place that specifically deal with these kinds of panels. They make sure that the material is either disposed of properly or reused. If you don’t want to risk having a hazardous waste problem then flexible silicon panels are your best bet.
Watch for UV degradation and delamination
Solar panels spend all day in the hot sun. But after a while, the powerful UV rays cause some chemical changes in the panels. If you have low-quality or cheap solar panels, they will undergo UV degradation. This is true for both flexible and rigid panels, though it’s much more common in flexible panels. You will notice when the UV rays have done damage when the plastic laminate begins to turn yellow and cloudy. This discoloration blocks the sunlight and lowers efficiency. If it gets really bad, your panel will undergo what’s called delamination, where the plastic laminate becomes detached from the solar cell. Panels that show delamination are ruined and should be disposed of.
Solution
Buy high quality panels! UV degradation and delamination are commonly seen in panels that are made with a kind of plastic called PET. High quality panels are manufactured with a more durable plastic called EFTE, which is resistant to UV damage and delamination. EFTE is also self-cleaning and 100% recyclable. Even if you’re on a budget, it’s well worth it to spend the extra money on higher quality panels. Trying to cut costs on cheap solar panels will cost you more money in the long run.
Hot Spots!
Flexible solar panels are more likely to be installed against a wall or roof, where they won’t get much room to cool off, unlike rigid panels, which can be mounted on racks. Again, while solar panels are meant to be under the sun all day, if the weather is especially hot, temperatures inside the solar cell can rise to extraordinary levels. This can cause hot spots inside the solar panel. Not only do very high temperatures lower efficiency dramatically, but hotspots can accelerate UV damage and delamination. Large temperature fluctuations can also cause microcracks in the solar cells, which further lowers efficiency and longevity.
Solution
Again, high quality panels are the solution. PET panels are susceptible to high temperatures, which cause delamination. Shelling out more money on EFTE panels will ensure that your solar array lasts. Factors like your climate will affect how hot solar panels can get. If you live in a hot climate, your panels are going to heat up, and there’s no way around it. The best thing you can do is maintain your panels and keep them clean and free of debris to keep up the efficiency.
Chemical Degradation
For those who live near the ocean or have flexible panels on their boat, chemical degradation from the ocean can be a problem. The constant barrage of salty air and ocean spray eventually corrodes and builds up on the plastic, lowering efficiency and damaging the solar cells. If your solar panels are constantly wet, the water can magnify the sun’s UV rays and accelerate degradation.
Solution
PET is the culprit here. PET panels are not well-equipped to handle the tough conditions on the ocean or near the coast. EFTE panels can withstand the salty air and marine environment. And like we said before, EFTE panels don’t suffer the discoloration and cloudiness that affect PET panels. If you’re looking for flexible solar panels for your boat, spend the extra money and go with higher quality panels.
Why You Should Still Buy Flexible Solar Panels
Flexible solar panels have their issues, but that doesn’t mean that you shouldn’t buy them. They’re very useful and have a wide range of applications. The flexibility and ability to bend means that they can be installed on curved surfaces, which means you can use them as a source of electricity on vehicles such as RVs, and even on boats. You can mount them on your roof if you want an aesthetically pleasing solar array with a flat profile. They’re also great for when you need a lightweight solution, like solar installations on plastic awnings and metal overhangs. In the near future, flexible solar panels might even have a role in space exploration.
Flexible solar panels have a few downsides, but all solar panels come with some obstacles whether they’re flexible or rigid. Most of these problems can be avoided by buying high quality solar panels. Maintenance is also key. Keep your panels free of dirt and grime, and inspect them periodically. It’s also important to be careful when you’re handling them. Even though they bend, flexible solar panels are still delicate. If you take care of your solar panels, then they will take care of you.
Are you shopping around for a set of flexible solar panels? We’ve compiled a list of the top ten best flexible panels from the most trusted brands. These are the most efficient, durable, and affordable thin-film solar panels on the market today.
Read also: Top-rated RV Solar Panel Kits
Frequently Asked Questions
Why are flexible solar panels less efficient?
Flexible solar panels use less efficient semiconductor materials than rigid solar panels. Since they are so thin, they also contain less material, meaning there’s less matter to interact with sunlight.
Can I put flexible solar panels on my boat?
Flexible solar panels are great for boats and vessels, although being in a marine environment will expose the panel to salt sprays, which can cause the panel to degrade faster than normal. Buying high quality EFTE laminated panels will protect you against chemical and UV degradation.
Are flexible solar panels toxic?
Some flexible solar panels use toxic chemicals as a semiconductor material. CdTe and CIGS both contain toxic chemicals, but unless the solar panels are destroyed and the material extracted, there is little harm to consumers. All solar panels are considered hazardous waste when disposed of, but CdTe and CIGS especially need to be disposed of properly. There are some recycling services specifically for these types of panels.
How do I avoid problems with flexible solar panels?
There are three main things you can do to avoid having any problems with your panels. First is to buy high quality solar panels. This ensures that you’ll be getting the best panels, and will minimize the chance of degradation. Second is to handle the solar panel with care. Flexible solar panels might have the ability to bend, but bending and folding them too much can cause microcracks, which lower efficiency. Thrid is to keep up with maintenance. Keeping your panels free of dirt and debris will ensure that you get the maximum efficiency and prevent degradation.