Flexible Solar Panels Unlock Longer Flights for Autonomous Drones

A team of researchers led by engineers from Johannes Kepler University Linz has introduced an ultra-light, effective solar panel design. The new flexible solar panels open the door for a variety of next-gen applications, including self-charging drones and more. Here’s what you need to know.

Why Drones Need Autonomous Power Systems

Man remains searching for autonomous energy sources to power humankind’s research and explorations. There are many scenarios where these systems are the only option. For example, the Mars helicopter Ingenuity demonstrated the power and added capabilities that these systems offer. The self-sufficient solar-powered drone made several unmanned flights on Mars, providing a treasure trove of data to engineers and researchers.

How Solar Power Enabled NASA’s Mars Helicopter

When you examine the success of Ingenuity, it’s easy to see that the drone’s autonomous power systems were a critical component of the mission. Without the ability to repower after extended usage, the Mar’s helicopter would have been a one-time flight, hardly worth the expense.

However, the ability of the craft to repower itself allowed it to conduct multiple missions with great success. Specifically, the craft utilized a solar panel to regenerate its six lithium-ion batteries. These batteries provided 90 seconds of flight time when fully charged.

Why Solar Is the Only Viable Energy Source for Space Drones

There are several reasons why only solar power would work for space travel needs. For one, the cost of bringing items such as fuel, motors, or other components is too high to make creating a system to handle these needs worth the investment.

Additionally, charging stations, cables, and other requirements would have made the helicopter too heavy to fly. On Mars, it takes a lot more lift to generate flight as the planet has different atmospheric conditions. As such, the engineers need to ensure it is as light as possible. Solar panels were the obvious solution.

What Are Perovskite Solar Cells and Why They Matter

Notably, of the many renewable energy options available to researchers, solar panels are the most available and make the most sense. Recent developments have made solar panels more efficient and lighter. The use of Perovskite solar cells has been a game changer for many reasons.

Perovskite solar cells provide engineers with the capability to create ultra-thin and flexible solar cells. These cells can provide high efficiency from a lightweight design. This design makes Perovskite solar cells one of the most commonly used when discussing powering drones.

Challenges Limiting Perovskite Solar Adoption

There are several issues that have hindered the further development and application of Perovskite solar cells. For one, they have poor operational stability. These devices are sensitive, and any sudden switch in motion, collision, or even dust can reduce the effectiveness of these devices. Thankfully, engineers have created some unique variations that can handle more specific use cases like autonomous drones.

Inside the Technology: 2D Perovskite Solar Cells

The perovskite solar cells integrate a layered crystal structure to create a lighter, more efficient design. These units are the most advanced type of solar panel available today. They integrate metal-halide sheets that utilize organic space to maximize light conversion. Notably, 2D perovskites have a chemical formula of RAn-1BnX3n+1.

Benefits of 2D Perovskite Solar Panels for Drones

There are several reasons why the 2D Perovskite cells remain a top choice for drone engineers. For one, they provide better thermal and moisture stability. The organic spaces built into these devices are crucial as they act as hydrophobic barriers.

Also, Perovskite solar cells offer improved photoluminescence quantum yield (PLQY) compared to the traditional version. The crystal structure enables these units to provide more stable and even power across the device. Interestingly, there are now 3D perovskite solar cells. The main difference is the precise arrangement of the crystals.

Study Overview: Lightweight Flexible Solar Panel Breakthrough

The study “Flexible quasi-2D perovskite solar cells with high specific power and improved stability for energy-autonomous drones,”¹ published in Nature, sheds light on a new type of solar cell.

The transparent-conductive-oxide-free quasi-two-dimensional perovskite solar cells provide reliable and stable power generation from a tiny and lightweight design. The new design could help power future space exploration and more.

The researchers at the JKU shared their design and manufacturing process for the ultra-lightweight quasi-2D perovskite solar cells. They began by ensuring the device was very thin and flexible.

The engineers also added alpha-methylbenzyl ammonium iodide directly into the photoactive perovskite layer. This step made it easier to apply an ultrathin polymer foil measuring only 2.5 μm. Impressively, this measures 20x smaller than a human hair. From there, it was coated with an alumina barrier layer, helping to optimize the solar generation capabilities further.

 Real-World Testing on Autonomous Drone Platforms

As part of the testing process, the team altered an off-the-shelf quadcopter to utilize their solar panels. Specifically, 24 interconnected 1 cm2 solar cells were attached to the device. Notably, these cells were ultra-thin and light, weighing less than 1/400th of the craft’s total.

The engineers performed multiple tests to ensure their device functioned properly and could produce the energy they predicted during the performance and stability demonstration. The device registered a champion-specific power of 44 W/g, averaging only slightly less at 41 W. The device was able to power an open-circuit voltage of 1.15 V. In total, it achieved an efficiency of 20.1%, averaging out at 18.1%.

Performance Results: Power Density and Efficiency Metrics

The results showed that the ultra-lightweight perovskite solar cells offered a cost-effective solution for autonomous energy harvesting devices. The unit’s remarkable performance and power output of 44W per gram make it stand out against today’s competing technologies.

Additionally, the test proved that these power units could enable drones to accomplish longer flights and perform consecutive charge-flight-charge cycles without wired recharging. These factors indicate that this approach will ultimately enable autonomous devices to operate globally.

Why Flexible Perovskite Solar Panels Are a Game Changer

Several benefits come along with the new solar panel design. For one, they provide ultra-light and power-efficient electronics with the capability to power themselves. In the future, your electronics may not need any plug or cost you to run. Instead, they may harvest energy directly using these solar cells.

Lightweight

The lightweight design of these solar cells makes them ideal for use in autonomous flight or other tiny applications. These cells are small enough to allow devices to still take flight without interfering with their operations. As such, they are sure to find more integration moving forward.

Adaptable

These solar cells are highly adaptable to meet a variety of use case scenarios. They can be formed into particular patterns or made to fit onto a small surface and provide enough energy to complete tasks. In the future, the engineers will seek to create even more flexible designs.

Highly Efficient

Solar panel efficiency has been a major concern since the earliest days of the technology. Today’s solar cells aren’t very efficient, with the majority of energy getting lost to heat and other factors. This latest design helps to improve efficiency and offers engineers more design flexibility without compromising performance.

Real-World Use Cases for Lightweight Solar Panels

There’s a wide range of applications that these new panels could be used in. For one, their ultra-thin design and power output make them ideal for a variety of small power generation needs. Here are just a few potential applications for these devices.

Aerospace Industry

The aerospace industry could utilize this tech in a variety of ways. From powering drones and crafts with unlimited range, to enabling space exploration to new planets. Already, the aerospace industry has integrated previous iterations of this tech to achieve remarkable milestones. Now, the technology is ready to power a new generation of explorers and scientists.

Wearable Electronics

Wearables are a fast-growing tech sector that spans multiple industries. These devices include a lot more than your smartphone. There are medical devices that register critical data for patients that could see expanded usage and lifespan thanks to this tech. Also, personal safety devices could run longer and become more effective.

Internet of Things

The IoT is a massive tech sector that includes billions of smart devices. These devices are currently reliant on batteries and power sources. In the future, they may not need any of these items as solar power could help them achieve the same results with less effort. Notably, billions of smart devices fall into the IoT category. As such, integrating self-power capabilities would be a game-changer.

Search and Rescue

Another major point of interest is the use of these systems to power search and rescue drones. Already, the use of soft robots that can conform their body to fit in tight spaces like moving through pipes or cracks is seen as the best option for future disaster and rescue efforts. Adding a self-powered system to these devices would enhance their capabilities and enable prolonged operations.

Mapping

Solar powered drones would be the ideal solution for large-scale mapping operations. You may think that mapping is an old science, but the reality is quite different. Every day, the Earth changes, and specific boundaries, resources, and other vital characteristics change. As such, mapping out these changes is a vital aspect of tracking the environment and other crucial developments.

Wireless solar-powered mapping drones could traverse massive ranges and provide updated mapping details without any human intervention. Making these devices solar-powered would help them to achieve their goals without all the added delays associated with coming back to the charging stations.

Meet the Researchers Behind the Breakthrough Design

Johannes Kepler University Linz researchers led the flexible solar panel study. The paper lists Bekele Haile Gnaw, Stepan Demchyshyn, Christoph Putz, Lukas E. Lehner, David Schiller, Roland Pruckner, and Martin Kaltenbrunner as the key authors. Now the team seeks to improve on their design, making it smaller and more effective.

Stock Spotlight: First Solar and the Future of Solar Tech

There are several companies leading the solar panel race. These firms continue to push innovation to new heights to make smaller and more efficient panels available to the masses. This latest development is sure to help these firms achieve their goals. Here’s one company that is positioned to take full advantage of these developments.

First Solar entered the market in 1999 as First Solar Holdings. Its goal was to provide high-end and efficient solar panels to industrial and enterprise-level clients. As such, its primary market is providing panels to large solar plants. The company is headquartered in Tempe, Arizona.

Since its launch, the firm has expanded its operations and product offerings to include a range of solar-related options. Notably, the firm pioneered ultra-thin semiconductor technology and has been instrumental in driving the need for increased recycling in the solar panel sector. Today, it is considered one of the most environmentally friendly options for solar panel manufacturing.

First Solar has experienced a drawdown in its stock price over the last year, partly due to the conflicts in Ukraine and other factors. Despite the value drop, many analysts predict this stock to see growing demand in the future.

The company currently has new products in development and operates manufacturing facilities in the US, Malaysia, and Vietnam. Those seeking a reliable and recognized solar stock should consider doing more research into FSLR.

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The Future of Solar: Cable-Free, Self-Powered Devices

When examining the technology and potential of this study, it becomes clear that the future will likely be driven by renewable energy sources, such as solar. As these panels become more affordable, smaller, and efficient, they’re going to see a lot more integration.

In the future, you may not have to change your electronics; instead, you may just set them by the window for 10 minutes. All of this and more is possible thanks to the innovative concepts put forth in the flexible solar panel study.

Learn about other renewable energy developments here.

Studies Referenced:

^{1. Hailegnaw, B., Demchyshyn, S., Putz, C. et al. Flexible quasi-2D perovskite solar cells with high specific power and improved stability for energy-autonomous drones. Nat Energy 9, 677–690 (2024). https://doi.org/10.1038/s41560-024-01500-2}