When you think of solar panels, what typically come to mind are the dark, rigid panels mounted on rooftops: heavy, immobile, and rather expensive. It may, therefore, come as a pleasant surprise to learn out about flexible solar panels.
What are flexible solar panels, and how do they work?
In contrast to conventional (flat) solar panels, flexible solar panel technology enables solar power to be generated by wafer-thin, light, and bendable panels that you can carry with you on the go. In fact, their portability is their primary selling point. It also helps that they are light on the pocket, with a 100-watt flexible solar panel available in the market for as little as $100.
This guide explores this new and upcoming technology, the various uses in the industry, and a helpful buying guide, so you are equipped to make the best choice for your needs.
Underlying photovoltaic technology
Despite the rather obvious (and perhaps superficial) differences, flexible solar panels work a lot like conventional (flat) solar panels, as they are based on the same photovoltaic technology—the ability to generate solar power from direct sunlight absorbed by the material.
In fact, all forms of solar panels are strategically manufactured in dark blue/black shades, in order to absorb the maximum amount of sunlight (during daylight). This, in turn, will lead to a higher amount of power generation.
While conventional solar panels used for powering residences and commercial complexes are larger in size and wattage (typically multiple panels of 340-watts of power), and hence their bulky size, flexible solar panels are made to serve low-wattage power needs, and typically come in 50-watts to 300-watts capacity. In addition, this can be stored in a battery for later use.
For this reason, they are an especially useful power-bank that comes in handy when you are on the go. They can thus be comfortably used in RVs, boating equipment, marine equipment (including large yachts), on camping trips, during long-distance travel, and even for daily use as the primary source of power when you are living off the grid.
Major types of flexible solar panels: widely used and under commercialization
Here, the “type” refers to the underlying source material used in the panels. Accordingly, there are 3 major types in current use:
- (Silicon) Crystalline flexible solar panels
- Thin-film flexible solar panels
- Flexible panels made of organic cells/materials
Type I: Crystalline flexible solar panels
These are most commonly used in the market, and are made of the same silicon material used to create conventional panels. Here, a solar “panel” is comprised of many crystalline, photovoltaic flexible solar cells.
If the underlying material is silicon—which is incidentally found in plenty in beach sand—then how is it that conventional panels are flat and bulky while flexible solar panels are thin and lightweight?
This is because they are stacked differently based on thickness. For instance, for lightweight solar panels, the silicon wafers are sliced to a few micrometers (μm) thick, giving them the illusion of being flexible as they can bend up to 30 degrees.
In fact, this 30-degree flexibility is more than adequate for it to be easily mounted on curved surfaces, including boats. They are also often used as flexible solar panels for RV (also called caravan solar panels). In contrast, the wafers in conventional solar panels are sliced at about 200μm thick, thus making them thicker and heavier.
Next, the thin-layered flexible silicon panels are placed between a protective layer—typically made of plastic—in order to extend durability and portability. (Compare this with thick glass layers used in rooftop solar panels.) As you can imagine, these lightweight solar panels can generate a limited amount of solar power, and thus come in 50-watt, 100-watt, 200-watt, and 300-watt varieties.
However, they have a reasonable efficiency (15%–25%) of converting light into energy, and can hence be mighty useful as energy banks to power your RV during a camping trip, a boat/yacht, or even most electronic devices for a day when you find yourself unexpectedly off the grid. For this reason, they are heavily used in the marine industry (including on fishing boats).
Type II: Thin-film flexible solar panels
This is a relatively nascent technology, where a photovoltaic material is printed or pasted on a thin surface (including cloth, thick paper, aluminum sheets, etc.). Without the protection of silicon, these are considered far less durable than their crystalline counterparts. However, this is still a growing technology, so a lot can happen in the future.
The primary advantage of using thin, portable solar panels is their super flexibility. They can be rolled up for storage and thus ideal for camping trips, where you may not care if they last for the following few years. This also makes them immensely lightweight, with some products weighing in at a mere 4 pounds.
Type III: Flexible panels made of organic cells/materials
The research presently on course at MIT works on producing robust, flexible solar panels made mostly of organic material. The primary challenge so far had been the brittle nature of the electrodes. In a recent breakthrough, graphene electrodes were introduced. With this, the solar industry has big expectations of producing higher quality solar panels with enhanced flexibility and extended durability.
Key advantages and disadvantages of flexible solar panels
Here, you may be surprised that there are as many advantages as there are disadvantages (or perhaps limitations with present technology). Highlights are listed below.
- Serve as eco-friendly energy banks (battery needed)
- Lightweight and portable
- Easy on most pockets
- Bendable enough to be multi-functional, as compared to conventional (flat) solar panels
- Size matters, so limited power generation and storage. Even with an efficiency of up to 25%, you only get up to 300-watt flexible solar panels.
- Less durable than solar panels. For instance, even a high-quality solar panel from Renogy comes with a 5-year product warranty, whereas a conventional solar panel can easily have a lifetime of 20–25 years.
Prominent applications of flexible solar panels
Flexible solar panels offer a huge opportunity for those wishing to seek a life off the grid, at least for a few days.
Due to their low cost and easy portability, they are ideal for:
- Camping trips, as power banks on your tent. They can also be safely rolled and stored when not in use. (These are also called camping solar panels.)
- Long-distance travel in an RV. Of course, you could also carry a noisy generator for your power needs, or simply enjoy a serene drive with a flexible solar panel installed on your RV!
- For boating/fishing/yachting trips. Again, ditch the generator, and let the fish be lured by the serenity of your noise-free environment. (These are also called solar panels for boats, or “flexible solar panels marine”.)
- Daily power backup. Do you find yourself constantly on the road, perhaps off the grid, panicking about your phone losing charge? Instead, you can slap on a flexible solar panel on top of your vehicle and allow it to serve as your sleek, eco-friendly power-bank.
Things to consider before buying
So, you are planning to invest in your first eco-friendly, portable, flexible solar panel. Congratulations on making this smart decision! Next, what factors should you consider in order to choose the best flexible solar panels? Read on to know more below.
- Power: This is often the first and foremost criteria in choosing the right flexible solar panel. This is measured in terms of wattage. The more the power, the higher the number of devices you can plug in, possibly for a longer period of time. For instance, a 100-watt flexible solar panel is typically used on boats for 2–3 hours, and higher wattages (like a 200-watt flexible solar panel or 300-watt flexible solar panel) are used in RVs or on camping trips. But of course, the wattage is directly proportional to the cost. Today, you can also get a 100-watt flexible solar panel for around $100.
- Efficiency: This refers to the rate at which the flexible solar panel is able to convert the (day) light it absorbs into usable energy. For instance, 15% efficiency is a basic standard and means that 15% of the total light absorbed is being converted to solar energy. A high quality flexible solar panel can offer up to 23–25% efficiency.
- Durability: This depends on the quality of materials used in the panel. Plastic is invariably used to sandwich the PV cells, thus protecting them from dust and corrosion. Here, ETFE plastic offers better durability and light transmission over cheaper varieties, including PET and PTE plastic. Moreover, crystalline solar panels, although a little more expensive, are undoubtedly superior to their thin-film counterparts (at least with present technology). Water-resistance is another alluring feature offered by leading manufacturers, and is especially useful in the marine industry.
- Bending angle: 30 degrees is considered an acceptable bending angle with most crystalline panels. Also, do take special note of Renogy’s surprisingly durable 248-degree bending solar panel—available in 50-watts, 100-watts (priced at $175 on Amazon), and 160-watt varieties—with a 5-year product warranty.
- Installation: The good news is that the installation of flexible solar panels is mostly a do-it-yourself job. In fact, some can simply be stuck on your RV using adhesive or Velcro. Yet, look for a company that offers a standard user manual with an installation guide. If the company is willing to invest in a quality user manual, then you can trust the quality standard they promise with their product.
- Size and weight: There may not be much variance to these figures, with the lightest of them starting at 4 pounds (from Renogy), and can go up to 8 pounds—still at portability levels.
- Warranty: Again, these may be based on the quality of the product. For instance, Renogy offers a whopping 5-year product and materials warranty and 25-years on power. SunPower—the country’s leading manufacturer—offers 2-years on product and materials and 5-years on power.
Here, industry certifications can also be used as a measure to gauge the quality of a product. Hence, look for manufacturers that promise ISO9001 and IEC61215 certifications on their flexible solar panels.
Flexible solar panels: Application and helpful buying tips
This guide provides 3 alternatives.
Directly from manufacturers
This will give you perks such as sensational service, high-quality products with extended warranties, and free shipping (at times).
For your convenience, consider the top 4 top manufacturers that regularly ship to U.S. consumers.
- SunPower: Industry leader and trusted U.S.-based firm. They normally offer a 2-year product warranty on most SunPower flexible solar panel products.
- Renogy: Also U.S.-based, and come with the best reviews for their 100-watt Renogy flexible solar panels. This has the ability to bend up to 248 degrees and comes with the best warranty of 5-years on product materials.
- Sunyee: Australian brand, uses SunPower’s crystalline cells in most of its solar panel products. They typically offer a 2-year warranty on Sunyee flexible solar panels.
- Solbian: Italian brand, also uses SunPower crystalline cells for their products. This company regularly offers a 5-year world-wide warranty, making them the top and preferred brand for Solbian flexible solar panels used in the marine industry.
From top E-com portals and global marketplaces like Amazon
This is recommended if you are looking for trustworthy brands with high standard products and hassle-free shipping facilities.
Tips to get the best deals are as follows:
- If possible, wait for their best deal times, like festive holidays, year-end sales, etc.
- Prefer options offering extended warranty or damage-free shipping (like Amazon Prime).
- They sometimes offer free-shipping when you club your purchase with a sponsored product.
From Chinese led online marketplaces like AliExpress:
If price is the primary factor, these Asian marketplaces are your best bet.
- Great prices with frequent deals, so price is the lure here.
- Look for explicit details on the product quality (including industry certifications), user manuals, contact info of seller, etc. to avoid cheap products that barely last 1-time usage.
- Read the user reviews—they can provide the key to determining the authenticity of the seller/product.
A brief note on budget
Considering that flexible solar panels are designed to fit smaller energy needs and hence smaller pockets, the budget can range from $50–$60 (Windy Nation, Giaride) to $250 from SunPower for the same 100-watt panel. Higher power panels can go up to $500. In addition, cheaper products may also imply the use of cheaper and less durable materials such as PET plastic. comment↓