Losing power in the middle of nowhere is one of the worst off-grid scenarios you can experience. Luckily, solar cell technology is always one step ahead. Let’s take a look at the most efficient solar panels of 2021, including a portable strip that you can directly plug your phone into.

That’s right. Solar panels are getting smaller, lighter, and easier to use. Plus, they’re becoming more efficient, paying for themselves in a shorter time frame. 

7 Most Efficient Solar Panel Reviews

What are the best solar panels, and how do you choose one? To answer this, we will be comparing the 2021 panels based on their power output, efficiency ratings, and cell type. These factors depend on what setting you’ll be using your solar panels. So let’s get to it.

PRODUCT NAME DETAILS
Best Solar Panel Best Solar Panel Renogy Solar Panel Renogy Solar Panel
  • Controller allows power expansion
  • Efficient solar panel with multi-layer protection
  • Cable labels are confusing
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Budget Pick Budget Pick SUNER POWER Solar Panel Kit SUNER POWER Solar Panel Kit
  • Complete kit with 25 year warranty
  • 3-Stage charging
  • Low power output
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BougeRV Solar Panel BougeRV Solar Panel
  • High-efficiency solar panels
  • Charges under cloud cover and low light
  • Comes in one really big panel
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HQST Solar Panel HQST Solar Panel
  • Ultra-durable solar panels
  • High operating efficiency for a polycrystalline cell
  • Bare panel with no accessories
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PAXCESS Solar Panel PAXCESS Solar Panel
  • Quick charging USB and C-Type output ports
  • Ultra-slim portable design with carrying case
  • Not suitable for prolonged outdoor use
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ROCKPALS SP003 Solar Panel ROCKPALS SP003 Solar Panel
  • 3 USB Charging Ports
  • Made from Oxford Cloth for water resistance
  • Not tested against solid objects
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Jackery SolarSaga Solar Panel Jackery SolarSaga Solar Panel
  • IP65 for rugged outdoor use
  • High solar panel efficiency
  • Not compatible with other solar generator brands
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Still unsure which of these most proficient solar panels is best for your needs? Continue reading to know everything you need to about each model on our list.

1. Renogy Solar Panel – Best Solar Panel

Renogy Solar Panel

Specifications

  • Efficiency: 21%

  • Max Power Output: 100W
  • Power Voltage: 18.9V
  • Solar Panel Type: Monocrystalline

If you need a panel that can hold more solar power and withstands its lifetime outdoors, then the Renogy Solar kit is your best bet. 

The 100-watt panel is a good size for those starting their solar journey. But the best thing about this kit is that it’s future-proof. The upgraded charge controller allows you to add three more solar panels to your system. Here’s a quick tutorial on how to do it.

However, this solar panel kit is a bit trickier to assemble. The bare wires that go into the charge controller can come off easily if you’re not familiar with wirings. We suggest hiring an electrician to prevent live wires dangling around your setup in the future.

Once you have everything set up, these high-efficiency solar panels are very reliable. Plus, it has super solid framing and a 6-layer protective coating. Both elements keep the monocrystalline cells running for decades. If you’re still unsure, maybe the 25-year warranty and EL certification that checks for microcracks will ease your mind. Overall, this is the best solar panel you can get for its price range. 

2. SUNER POWER Solar Panel Kit – Budget Pick

SUNER POWER Solar Panel Kit

Specifications

  • Efficiency: 18.5%

  • Max Power Output: 20W
  • Power Voltage: 12V
  • Solar Panel Type: Monocrystalline

Start your off-grid setup with Suner Power’s solar kit. It’s beginner-proof and the best solar panels for RV if you’re on a budget. 

You don’t get much power with this 20-Watt unit, but you get high solar panel efficiency thanks to its monocrystalline cells. And if you choose the best solar battery with a big capacity, you can expand your solar energy system. 

Aside from needing a battery, the kit also needs mounting accessories for your RV or roof. Otherwise, it’s a complete free-standing setup that comes with all the connective cables and even a handy charge controller that works on three modes. 

  • You can keep it running until the battery dies. 
  • Run it from dusk till dawn or 
  • Run it for a certain number of hours after sunset.

It sounds complicated, but don’t worry. The package comes with an illustrated manual, making it super easy for solar newbies. 

3. BougeRV Solar Panel

BougeRV Solar Panel

Specifications

  • Efficiency: 21.2% 

  • Max Power Output: 180W 
  • Power Voltage : 21.6V 
  • Solar Panel Type: Monocrystalline

You might be looking at the specs thinking, “These are bigger and slightly more efficient solar panels. Why isn’t THIS the top pick???” 

Well, despite having almost twice the wattage for nearly the same price, these high-efficiency solar panels aren’t for everyone. For one thing, the BougeRV solar panel kit doesn’t come with a charge controller. The next concern is the size. This thing is one massive solar panel that might not even fit the roofs of some vans or rigs. However, it’s lightweight despite its size, which slightly compensates for not being foldable or modular. It’s also very durable, able to withstand less than ideal conditions.

The basic kit is the best solar panel for homes or those who have experience setting up mobile solar systems. Also, because the 180-watt panel is not in the standard hundred-watt mark, it falls in the awkward range for expansion. You need some solar know-how to figure out the math when it comes to configuring multiple panels. Otherwise, you can end up overloading your battery. 

Regardless of using the panel as a single or combo unit, the performance will be top-notch. The specialized monocrystalline cells help achieve higher efficiency ratings even under cloud cover. Plus, you have the same 25-year warranty to back you up.  

4. HQST Solar Panel

HQST Solar Panel

Specifications

  • Efficiency: 16.5%

  • Max Power Output: 100W
  • Power Voltage: 18.1V
  • Solar Panel Type: Polycrystalline

Let’s take a look at a polycrystalline solar panel for a change. 

As expected, the HQST Solar Panel has a much lower conversion than the previous list items. But at 16.85% efficiency, it’s not a far cry from our monocrystalline budget pick. The bypass diodes in the solar panel definitely help increase its overall efficiency, even during cloudy days.

In terms of juice, this 100-watt powerhouse can definitely run with monocrystalline products. Don’t underestimate its smaller size, either. It has the same durability as the BougeRV solar kit, so you don’t have to worry about working the unit under snow or strong winds. This solar panel is also much lighter, making it easier to adjust the panel’s position individually according to the sun’s orientation.

The kit doesn’t come with a charge controller or accessories. But the solar panel has pre-drilled holes which are compatible with different mounting systems. It also has a waterproof junction with connecting wires. If you decide to get a few panels, make sure you pick the correct battery that can process both the voltage and wattage of the combined solar panels. All things considered, this is one of the highest efficiency solar panels you can get for just double the price of our budget pick.

5. PAXCESS Solar Panel

PAXCESS Solar Panel

Specifications

  • Efficiency: 23%

  • Max Power Output: 120W
  • Power Voltage: 18V
  • Solar Panel Type: NA

PAXCESS has the best portable solar panels on our list. The whole setup folds neatly into a 1.38-inch thick carry case, making it perfect for staying powered up during camping trips.

Don’t count this 120-watt foldable unit out when it comes to performance because it has an impressive solar efficiency of 23%. You also won’t have a hard time reaching this peak, thanks to the adjustable kickstand. The solar energy and efficiency combo makes this unit perfect for charging power stations. 

The best part? You don’t need a battery or inverter! The kit comes with four adapters compatible with most solar generators, allowing you to hook up your power station directly.  

Plus, it has a USB 3.0 and C-type port for your mobile phone or tablet. Both are quick-charging able to juice up your iPhone to 50% in just half an hour. But these ports only have a maximum output of 24W and 18W, respectively, meaning they don’t have enough power to charge bigger devices like laptops that run on at least 45W. 

One downside to the ultra-thin design is that it sacrifices durability. You can’t expect this unit to withstand harsh environments, let alone shocks from a hard drop.

6. ROCKPALS SP003 Solar Panel

ROCKPALS SP003 Solar Panel

Specifications

  • Efficiency: 21.5-23.5%

  • Max Power Output: 100W
  • Power Voltage : 16-18V
  • Solar Panel Type: Monocrystalline

Our next solar panel on the list is the Rockpals SP003, a foldable solar panel that tucks away like a briefcase. It’s a slight upgrade from the previous item with ten connectors included instead of four, giving you a wider range of generator compatibility. 

You also get the quick-charging USB ports to power up more mobile devices at the same time. But unlike the previous item, there is no C-type cable port available here, and the overall solar energy output is much lower at just 100W. Using several of these solar panels can also be tricky since they don’t work together in parallel. 

In the solar panel efficiency department, this monocrystalline panel takes the cake. Thanks to the six-cell layers, solar production boosts to 23.5%. Plus, the entire system is more durable than its ultra-thin counterpart, with a thicker construction made of Oxford cloth

The panels themselves are rated IPX4, making them water-resistant to splashes from all directions. But that doesn’t make it completely waterproof and definitely not shockproof. In any case, a little more padding never hurts and adds to its good standing as one of the best solar panels for camping.

7. Jackery SolarSaga Solar Panel

Jackery SolarSaga Solar Panel

Specifications

  • Efficiency: 23%

  • Max Power Output: 100W
  • Power Voltage: 18V
  • Solar Panel Type: Monocrystalline

Let’s cap off the list with the Jackery Solar Saga, one of the most efficient solar panels around. Its specialized design provides you with a 100-Watt output and extreme durability. Here’s what makes these premium efficiency panels worth the big bucks.

First up, the construction design. Unlike other foldable panels, this unit only folds in half, with both ends having handle loops. It’s sleek, simple yet durable, with an IP65 rating. The fluorine-based outer casing protects your solar panel from corrosion and splashing water. Its specialized material also allows the unit to operate safely well below freezing temperatures. 

The next premium feature is the solar panel’s certification for having no emissions or noise, making it environmentally safe. 

Being a Jackery product, expect the compatibility to be limited to fellow Jackery solar generators. You may not get connectors for other power stations, but you get two USB ports to charge your mobile devices quickly. And unlike the previous product that has a vulnerable junction box, this unit has a water-resistant pouch for all the ports and cables. 

Solar Panel Buying Guide

All solar panels may all look like flat waffle-like sheets. But don’t be fooled by their similar appearance because there is a significant difference in performance.

two men installing efficient solar panels

Our solar panel buying guide will give you an inside look into the panels, explaining the basic concepts of how they work and what to look for in choosing amongst the most efficient solar panels. 

Solar Panel Type

The combination of cells used in the solar system determines solar panel efficiency. Let’s check out the three primary types of solar panels and get to know how each one stacks up against the others (1).  

Monocrystalline

These solar panels use only pure silicon solar cells that melt a single crystal and engineer it into its own panel. Premium efficiency panels have multiple layers to increase solar conversion and durability. 

Monocrystalline solar panels take more time and effort, increasing the manufacturing cost for these high-efficiency solar panels.

Like the Renogy Solar Panel, most of our picks are high-efficiency solar panels with monocrystalline cells. 

Polycrystalline

As the name suggests, this solar cell uses several silicon crystals to form a Photovoltaic (PV) cell.  Since the particles are detached, they have lower solar panel efficiency compared to monocrystalline solar cells. The upside is that they are cheaper to manufacture. 

The only polycrystalline panel on our list is the HQST Solar Panel. We included it in our review because it has a solar efficiency close to the SUNER POWER Solar Panel Kit, a monocrystalline panel.

Thin-Film

The most budget-friendly and durable solar panel is the thin film type. But these are also the lowest efficiency solar panels because of the highly dispersed structure of silicon. Manufacturing involves only a fraction of the silicon used in solar panels. As a result, the solar sheets are very flexible and not prone to breakage. 

Out of the three cell types, monocrystalline cells are the most efficient solar panels because of their compact crystal structure.

Ultimately, choosing the type of solar cell boils down to a balance between solar panel efficiency and affordability. Later on, we’ll talk about other factors that will play, making the decision more crucial.

Solar Panel Efficiency 

Solar panel efficiency means how much solar energy is converted into electricity. Obviously, the more electrical energy produced, the more efficient the solar panel is and the more savings a household earns. 

But why do efficiency ratings seem so low in the panel’s spec sheet? Solar panel manufacturers make commercial panels with an average efficiency rating between 15-20% because most of the energy collected by the panels is lost in the process of conversion (2).  Many factors like solar technology also impact solar panel efficiency, which is why most solar panels can never be 100% efficient. 

What is Solar cell efficiency?

Solar cell efficiency is not the same as solar PANEL efficiency. The former refers to how well the PV material (monocrystalline or polycrystalline) absorbs solar energy. On the other hand, panel efficiency focuses on converting the collected energy into electricity (3). 

If you want to have a perfectly efficient solar system, the solar cells need to absorb as much solar energy as possible. At the same time, the rest of the panel components work to convert it into electricity.  

Factors that can influence the efficiency

Here’s a complete list of factors that can increase or decrease your solar efficiency (4).

  • Temperature
  • Irradiance
  • Dust, dirt, and other debris
  • Interconnection of the cells
  • Color of the backing
  • Cell type
  • Reflection

Calculating the Solar efficiency

Solar energy, although renewable, is extremely unpredictable. Therefore, measuring a solar panel’s efficiency occurs under controlled laboratory conditions (5). 

“Conditions under which efficiency is measured must be carefully controlled to compare the performance of one device to another.”

But you can also measure your solar panel’s efficiency using your solar controllers or voltage/amperage meters.

To do this, follow this simple equation (6):

solar efficiency formula
solar efficiency formula

For example, a 100W solar power with an area of 0.5m2 will have an efficiency of 16.67%. 

Power Output 

As with any electrical power supply, the output is measured in watts. The higher the wattage, the more power you have to keep electronics running. 

The same principle applies to solar panels, and the power output can be used directly from the panels, as in the ROCKPALS SP003 Solar Panel. But in most cases like the SUNER POWER Solar Panel Kit, the wattage is used up to charge a battery for emergency use later on. 

When choosing a solar panel for household use, you can figure out how many solar panels you need to power refrigerator by adding up the power output of several units and giving some allowance for safety. So if you have a 500-watt refrigerator, you’ll need at least a 600-watt solar panel. 

Warranty 

The best solar panel kits are not only efficient; they also have an extended warranty. Units like the BougeRV Solar Panel are well constructed and protected with a lifetime warranty (7). 

“Your solar panel’s performance warranty, which typically lasts 25 years, can give you a better sense of how much electricity to expect from your solar panel system over time.”

It’s crucial to extend the longevity of solar panels to maximize their value. You can slow down the degradation by using the solar panels under the indicated conditions and compatible batteries and inverters.

Cleaning and Maintenance 

Keeping your solar panels in tip-top shape can be as easy as removing debris regularly and wiping it down with a clean cloth after a downpour. Portable units like the Jackery SolarSaga Solar Panel are even easier to maintain because you don’t have to climb up rigs or roofs to access them. Make sure you keep portable panels in cool, dry places when you’re not using them.

Location and Placement 

Where you put your solar panels really depends on where you generally get the most sun. For bigger and stationary units like the BougeRV Solar Panel, make sure you mount them on adjustable brackets so you can maximize sun exposure. 

The PAXCESS Solar Panel is one of the best portable solar panels on our list, making it easy to position. Just make sure it doesn’t get blown away or thrown off. Tying it down helps keep it in place.

Read More: American Made Solar Panels

FAQs

  • Will Solar Panels Ever Reach 50% Efficiency?

    Yes, solar panels will eventually reach 50% efficiency with continuous solar research and development. Over the past few years, news of solar panel prototypes reaching 40% efficiency under lab settings is already spreading. The solar sector is developing fast, so keep yourself posted.

  • What Time Of Day Are Solar Panels Most Efficient?

    Solar panels are most efficient when the sun is high above the ground. Averaging out the seasons, this translates to between 10 am and 3 pm. Of course, the peak would be at high noon if there is no cloud cover or bad weather.

  • Do Solar Panels Damage Your Roof?

    No, solar panels do not damage your roof if they are correctly installed. Damage occurs when screws are drilled incorrectly or solar panel installation takes too many attempts in the same spot. Alternatively, you can wreck your roof by not laying your panels flat and locking them down during a storm. Depending on your mounting preference, a moveable bracket can sway with the wind, yanking your panel off the roof. Shingles and the roof material attached to the frame will naturally come off.

  1. Types of Photovoltaic Cells. Retrieved from: https://energyeducation.ca/encyclopedia/Types_of_photovoltaic_cells
  2. Photovoltaic Energy Factsheet. Retrieved from: https://css.umich.edu/factsheets/photovoltaic-energy-factsheet
  3. Solar Photovoltaic Cell Basics. Retrieved from: https://www.energy.gov/eere/solar/solar-photovoltaic-cell-basics
  4. Solar Performance and Efficiency. Retrieved from: https://www.energy.gov/eere/solar/solar-performance-and-efficiency
  5. Solar Cell Efficiency. Retrieved from: https://www.pveducation.org/pvcdrom/solar-cell-operation/solar-cell-efficiency
  6. Calculate the Solar Cell Efficiency. Retrieved from: https://infinitypv.com/learn/teacher-guides/solar-cell-efficiency?tmpl=print&learn-lan=
  7. How Long Do Solar Panels Last? Solar Panel Lifespan Explained. Retrieved from: https://news.energysage.com/how-long-do-solar-panels-last/