Lightweight Solar Panels: Maximizing Solar Energy Wherever You Go

When people think of solar systems, they picture huge panels on a building's roof. Solar technology has advanced exponentially, and today, homeowners and adventurous individuals can invest in lightweight solar panels to make the most of natural sunlight anywhere they go.

Due to the continued use of non-renewable energy, human-induced climate change is pushing the world to a climate catastrophe. During November's COP26, the UN acknowledged that the goal of limiting global warming to 1.5 is currently on "life support." In response to the climate issues discussed at COP26, the International Energy Agency (IEA) pointed out: "To ensure that we keep 1.5 alive, significant and widespread transformations in the energy sector are required, and that means providing solar solutions that benefit the people.

Lightweight folding solar panels are beneficial as they fit in any solar-system setup. For instance, if your roof isn't robust enough to handle the weight of conventional solar panels, you can install lightweight solar panels without compromising your roofing system's structural integrity. They feature a thin film that significantly reduces their weight. Furthermore, they can be shaped to match the dimensions of the installation space, making them ideal for uneven surfaces, such as carports.

What are Lightweight Solar Panels?

Some of the lightest solar panels are monocrystalline and polycrystalline panels, characterized by their thinness. These solar solutions are made up of silicon wafers, typically less than 200 micrometers thick. However, to make lightweight flexible solar panels, solar companies must narrow down the wafers' width to a few micrometers to create gaps between them, thus enabling users to fold them and even use them on unconventional structures.

The use of silicon cells is not something new. Ongoing research continues to advance solar panel technologies. Organic cells are quickly replacing silicon cells. The Massachusetts Institute of Technology (MIT) offered new insights into how lightweight PVC panels can use graphene electrodes. Silicon electrodes get brittle with time, limiting the flexibility of thin PV panels. The introduction of graphene electrodes means manufacturers can roll out ultra-thin, more flexible, and stable products in the future.

Types of Solar Panels

The PVC panels used for solar power generation can be categorized into three classes. They include monocrystalline, polycrystalline, and thin-film solar panels.

Monocrystalline Solar Panels

Monocrystalline PVC panels are the most common solar panels used in rooftop installations. They are manufactured through a process called the Czochralski method. A tiny silicon crystal is placed on a vat of hot silicon during the procedure. The result is a single silicon crystal known as an ingot. Manufacturers slice the ingot to make silicon wafers used in solar panels.

Monocrystalline solar panels are the most efficient solar panels on consumer markets, with a 17% to 22% efficiency rating. They are ideal for use in properties with limited roof space because it only takes a few panels to generate enough solar power to satisfy your electricity needs.

Their power efficiency depends on how fast electrons can move through the solar cells. Electrons move from silicon cells faster in a flexible monocrystalline solar panel as it only features a single silicon crystal. That enhances efficiency and power output, enabling them to generate up to 375 watts of energy.

Although many thin-film solar panels are built around amorphous silicon (a-Si), copper indium gallium selenide (CIGS), and Cadmium telluride (CdTe) (which we'll discuss later), it's not uncommon to find monocrystalline lightweight solar panels.

While most on-market solar options produce 100-110 W of energy and fold a maximum of 30 degrees, some lightweight folding panels bend up to 248 degrees, thanks to their 1-inch thickness. Besides, they have a straightforward installation procedure, perfect for DIY mounting. Weighing only 6.2 pounds, the panels are the most flexible in consumer markets today, making them ideal portable solar solutions for boats, mobile homes, and RVs.

Polycrystalline Solar Panels

Also referred to as multi-crystalline panels, polycrystalline solar panels are popular among homeowners and people who choose to live off-grid because their installation costs are relatively lower.

They are similar to their monocrystalline counterparts as they also feature silicon cells. The only difference is the cooling process. With monocrystalline panels, the manufacturing process results in a single silicon crystal, but polycrystalline panels have multiple crystals, hence their name - polycrystalline panels.

Multicrystalline solar panels have lower energy efficiency, ranging between 15% and 17%. Because polycrystalline photovoltaic (PV) panels feature many silicon cells, electrons can't move quickly to the cells, thus decreasing efficiency. That's why polycrystalline panels have a lower power output, ranging from 240W to 300W.

Thin Film Solar Panels

  • Copper Indium Gallium Selenide (CIGS)
  • Amorphous silicon (a-Si)
  • Cadmium telluride (CdTe)

Once the PV substance is deposited on the solid surface, it forms a thin, flexible sheet - the solar panel. Due to their design and solar technology, they have an efficiency rating of 10%-13%, although researchers have managed to create thin-film cell prototypes with 23.4% efficiencies.

Amorphous Silicon (a-Si)

The first generation of lightweight folding solar panels was manufactured using a-Si, a non-crystalline form of silicon. The material has a low-efficiency rating – about 5-6%. Therefore, it has a low power density, and users have to install them over a larger area to match the power output of crystalline modules. Still, DIY solar panel installation alleviates the need for panel assembly and roof penetrations common to traditional solar systems.

Copper-indium-gallium-selenide (CGIS)

The second generation of thin-film solar panels was built around CGIS PV technology. These solar panels are similar to a-Si panels as they are flexible and lightweight, and owners can effortlessly install them. The only difference is the efficiency rating. CGIS panels deliver 16% power efficiency, meaning they can convert 16% of solar energy to electricity.

CdTe Solar Panels

CdTe solar panels are the second most popular PVC panels after crystalline silicon, accounting for 5% of the global market. Their manufacturing process is cost-effective and quick, providing an alternative for users migrating to solar on a budget. The average solar efficiency of CdTe panels was estimated at 18% at the end of 2020, albeit other labs CdTe solar cell prototypes have delivered a record 22%.

CdTe thin-film solar cells have their benefits. They include:

  • Enhanced absorption – CdTe is a material with a small bandgap. It can be tuned from 1.4 to 1.5 electronvolt (eV), enabling the panels to convert solar energy to electricity using a single junction.
  • Low-cost production – Manufacturers create cadmium telluride solar panels using a throughput manufacturing procedure that rolls out complete CdTe solar modules from raw materials within hours.

What Are the Benefits of Lightweight Solar Panels?

The Pew Research Center conducted a survey that revealed a growing number of homeowners consider going solar. While only 6% of all US households have already migrated to solar energy, 46% say that they are seriously considering adding solar panels to their homes. The solar energy market is growing, thanks to the value and benefits that lightweight foldable solar panels offer. Some of these advantages include:

Low Investment Cost

One of the major upsides of investing in thin-film, semi-flexible solar panels is their low cost. In fact, they cost 30% less than crystalline silicon cell panels. Some manufacturers have even developed new technologies that further slash down the cost of operating thin-film panels to $0.75 per watt. That's half of what most competitors offer.

However, the pursuit for cheaper panel modules hasn't been smooth-sailing in recent years. Production levels have gone down primarily because many Chinese crystalline manufacturers have bolstered their production, and now the cost of traditional PVC panels has significantly dropped as well.

Minimal Rooftop Requirements and Straightforward Installation

A conventional solar panel has a thickness of 0.15-0.2 mm; weighs about 40 lbs. and measures 4-5 ft. wide. On the flip side, a thin film, the portable solar panel is 0.001 mm thick and weighs 4-7 pounds, making it much lighter than crystalline silicon cell PVC modules.

Crystalline solar panels require a solid roof to handle the system's weight. Besides, installation involves assembly and roof penetrations. A lightweight solar panel can be mounted on a roofing system that isn't strong enough to support conventional panels. Moreover, it comes with a convenient mounting system, such as peek-peel-and-stick or pre-drilled mounting holes for an effortless installation.

Improved Performance in Hot and Cloudy Weather

Usually, solar panels have the highest conversion efficiency when the temperature is 25◦ C (77◦ F). Nonetheless, the temperature of solar panels operating in the sun is often higher than that, reducing their power output. But thin-film flexible solar panels operate optimally regardless of the atmospheric temperature.

They have the best temperature coefficient. For instance, a-Si modules have a coefficient of 0.2% compared to crystalline panel modules' 0.5%. Whenever temperature increases by 1◦, thin-film cells' power efficiency reduce by 0.2%, while crystalline silicon cells' efficiency decreases by 0.5%.

Perfect for Power Generation on Cloudy Days

Typically, conventional panels deliver good PV performance when solar irradiance is 1000 W/m², but they barely operate under cloudy conditions. Crystalline cells usually absorb a sunlight spectrum of 400nm-1000nm wavelengths, which majorly contain visible light. Hence, their power efficiency plummets significantly during cloudy weather, when there's no visible light.

Thin-film solar panels have an extended spectrum-absorbing range and can utilize infrared and UV light. Consider CIGS thin-film cells; they absorb sunlight ranging from 400nm-1200nm, whereas CdTe PV cells absorb 250nm-1750nm. This property enables CIGS and CdTe solar panels to convert more natural light and operate for longer hours than their crystalline counterparts under overcast weather. Moreover, they are not dependent on the intensity and direction of sunlight and can deliver higher performance in the early morning and late evening, including cloudy and rainy weather.

Enhanced Aesthetics

Crystalline solar panels stick out on your roof, thus compromising your property's overall architecture and design. The solid black appearance of monocrystalline panels looks subtle on the roof, but the white spaces on these modules hurt their aesthetics. In contrast, polycrystalline panels feature mixed colors due to their manufacturing process. Each panel has a different shade of marble blue, which can be an eyesore.

Thin-film panels are the most attractive solar panels, delivering a clean, all-black appearance. Their thin, flat design, combined with their peel-and-stick installation process, ensures lightweight solar panels conform to the installation surface, no matter the design or texture. That makes them look attractive as they are minimally invasive of the roof design.

When are Lightweight Flexible Solar Panels Useful?

Thin-film folding solar panels are perhaps the most useful when you need portable solar solutions. Lightweight solar panels for RVs and caravans serve people who love exploring the outdoors and require comfortable living off the grid. They are also perfect for campers and hikers. With thin-film panels, they have portable solar generators that they can easily carry to their destinations.

Flexible thin-film panels can also be used on vehicle rooftops. When the car is idling, the solar energy generated can power the AC system while providing the much-needed electricity to operate Wi-Fi, refrigeration units, power plug-ins, etc., without burning fuel. Whether used commercially or for recreation, lightweight solar panels for caravan significantly reduce car fuel costs, minimizing our carbon footprint no matter how far we go.

Additionally, people can use lightweight solar panels on floating solar reservoirs and canal waterway covers. Not only do they prevent the loss of water due to evaporation, but they also generate enough renewable energy to move water. Besides, they provide a more cost-effective power generation solution than the bulky glass solar panels with large support structures and floatation components. Lightweight, bendable solar panels on large water towers can adhere to the steel surface, delivering the solar power required to pump water to the reservoir. At the same time, they provide backup energy when utility power is depleted.

Conclusion

Gone are the days when solar panels were only limited to buildings' rooftops. Technology advancements in the solar industry have led to the creation of thin-film solar panels that offer people the freedom to tap into solar energy no matter their location. The manufacture of lightweight crystalline panels means portable panels achieve power efficiency that rivals the conventional panels. Moreover, lightweight, foldable solar panels have user-friendly mounting systems, perfect for DIY installations. If your roof's dimensions or strength can't support traditional solar panels, you can invest in thin-film panels to reduce your carbon footprint while enjoying power independence.

Renogy is committed to providing solar products that accelerate the use of renewable energy for sustainable living and power independence. We offer a wide range of portable power stations, chargers, and lightweight solar panels.