Solar Panel Efficiency Breakthroughs: All You Need To Know

Solar Panel Efficiency Breakthroughs: All You Need To Know

There is always the hope that a significant discovery will be made that will completely transform things. Scientists have recently broken the record for the efficiency of solar panels, and this breakthrough may have significant implications for the future of renewable energy sources. This is not only additional hype; rather, it is an indicator of where things now stand and where they are headed. Nevertheless, this is hardly the only significant piece of solar-related news to come out in 2022. From perovskites to organic solar cells, there have been a lot of fairly recent developments in each of these areas. Therefore, what does this imply for people like you and me? Let's see if we can reach a conclusion on this, shall we?

Over the last several years, I have written a lot of articles on solar panels, and I have also shared my own experiences with installing solar panels on my house. Solar energy is essentially the grandpa of the family of renewable energy sources, and for good reason: there is an unlimited energy source beaming down on us literally every day that is just waiting to be tapped. Solar power has been around for a long time and has shown its worth. Only one hour's worth of energy from the sun is enough to meet the energy demands of the whole planet for an entire year. This is one of the reasons why I find it so fascinating, but unfortunately, there is no way for us to store all of that energy.

Along these same lines, many individuals have left comments essentially stating that "solar panels are not efficient enough" and "most likely will never be." This style of thinking never ceases to astound me due to the fact that the technology that we all take for granted now were the breakthroughs of a decade ago, which means that the breakthroughs of today are where things are headed.

In the space of only a few short months, we have seen a number of fascinating developments in solar energy, some of which we have been waiting for over 10 years. Your wait may be over if you have been holding off for the appropriate benchmark, such as a target efficiency rate or the appropriate type of material to get into commercial use. However, before we get to that, let's go over some of the more interesting updates, as well as some of the catches, and discuss what it all means for us.

Record efficiency rates and design updates

Record efficiency rates and design updates

To begin, we need to discuss some of the most recent and significant developments in the solar industry. One such development is the fact that the National Renewable Energy Laboratory of the United States Department of Energy has just established a new record for the efficiency of solar cells at 39.5%. This was performed under lighting conditions that were comparable to those of the sun, which is a significant improvement over the previous world record. In earlier tests, solar cells worked up to 47.1% of the time in the year 2019, but this was only true when they were exposed to a lot of concentrated light.

So, what was their strategy? NREL used inverted metamorphic multijunction (IMM) cells in their record-breaking cells rather than increasing the amount of light used, as was done in the previous record. These cells feature three layers that are stacked on top of one another, and each layer is constructed of a different material. The gallium indium phosphide layer is on the top, the gallium arsenide layer is in the middle, and the gallium indium arsenide layer is on the bottom. Because each takes in a distinct range of light wavelengths, the cell is able to extract a greater quantity of energy from the whole light spectrum. In the intermediate layer, you can also locate three hundred "quantum wells," which turned out to be the secret to these cells' newly discovered level of efficiency. These wells made the bandgap inside the cell bigger, which meant that the cell could take in more light.

The National Renewable Energy Laboratory (NREL) is not the only organization that has been successful in extracting additional energy from solar cells by modifying their design. The quantity of energy that can be absorbed by wafer-thin solar panels has risen by 25% thanks to the work of a team that was co-led by the University of Surrey. The individual panels have a thickness of just one micrometer, but they are constructed with a layer that has the appearance of honeycombs and functions to absorb light. The textured pattern of these thin photovoltaic cells helps to trap light inside the solar cell, which in turn increases the efficiency of the solar cell. In silicon cells, about one-third of the light that strikes the cell often just bounces straight off. The patterns seen in nature, such as those found on butterfly wings and bird eyes, provided the inspiration for this design. The researchers observed absorption rates of 26.3 mA/cm2 in the laboratory, which is a 25% rise over the previous record, which was 19.72 mA/cm2 and was set in 2017.

The efficiency rate isn't too awful either: these cells have an efficiency rate of 21%, and it is anticipated that subsequent modifications will push that figure higher, potentially even higher than other photovoltaics that are currently accessible.

Perovskite developments

For some time now, perovskites have been a glimmering lighthouse on the horizon of the solar industry for some time now. Traditionally, solar panels have been synonymous with silicon, which is utilized in around 95% of the panels on the current market. In earlier videos, I briefly discussed some of these topics.

Perovskites are a class of man-made materials that may be classified according to the crystalline structure of the substance. In general, they coat surfaces readily, which implies that they may be utilized in cells either by themselves or in conjunction with other forms of technology (like our existing crystalline silicon cells). Since these perovskite semiconductors can turn the energy-rich blue spectrum of sunlight into usable energy, they can be used with silicon sub-cells to get efficiencies of up to 30%, which is higher than the 25% efficiency of single-junction perovskite cells.

Perovskites are supposed to fulfill all three of these requirements: they should be inexpensive to manufacture; they should be competitively efficient; and they should be thin and lightweight enough to be applied nearly anywhere. Because of this, researchers have been chewing at the bit to get perovskites commercialized, but there have been a few practical barriers to overcome before perovskites can try to give silicon cells a run for their money in terms of cost effectiveness.

The first issue is the durability component, which is one of the greatest challenges that perovskite faces. However, perovskite cells are thin and light, which is a benefit. However, this also makes them brittle, which is not ideal for a material that will be exposed to elements such as rain, sun, hail, and everything in between. It used to be that the samples would shatter before the researchers could even make it across the lab to evaluate them. If the samples can't be handled in the lab, they won't be able to handle the stresses put on the solar panel frame in the real world, such as those caused by the occasional hailstorm, wind loading, and torsion.

They've certainly come a long way since then, which is cause for celebration. According to the findings of research that was published on April 9, organometallic compounds might be utilized as an addition to assist in increasing the longevity, efficiency, and stability of the cells. After 1500 hours of usage, the upgraded cells still maintained 98% of the cell's original 25% power conversion efficiency rate. The improved cells also passed the tests for stability in damp heat and kept a 25% power conversion efficiency rate.

Researchers have also been delving further into the reasons behind why perovskite functions the way that it does, both the positive and the negative aspects of its operation. Imaging methods were utilized by researchers in May 2022 at Cambridge University and the Okinawa Institute of Technology (OIST) in Japan to investigate the structure of perovskite films on the nanoscale, particularly when light was truly incident on the film. They discovered one of the factors that contribute to the notorious photodegradation issue of perovskite, and it is called nanoscopic trap clusters. Because of these flaws in the material, which manifest themselves as pockets as a result of the cell processing, the film will eventually have a lower overall efficiency and will be structurally brittle. The most effective method for overcoming these efficiency-reducing carrier traps is to eliminate them during the manufacturing process by fine-tuning the structural and chemical design. This is the case because meticulous tuning is required. If you make these adjustments such that they are compatible with production on a wide scale, you will have a formula that will allow you to produce more of these films while also improving the quality of their performance.

Perovskite developments

Organic solar cells

Imagine for a moment if the production of new solar cells was as straightforward as the printing of a newspaper. This is the goal that the manufacturers of organic power cells have set for themselves, and at this point, they are prepared to provide this technology to markets all over the globe.

Printing photovoltaic material onto flexible materials such as plastic sheets is one method for manufacturing organic power cells. Flexible, lightweight, and fast to create using printing technology (the same process as printing newspapers! ), these paper-thin solar cells are made completely of organic materials. In addition to being one hundred times lighter than silicon-based cells, they cost one-half as much to produce. Currently, one square meter weighs less than two kilograms, but by 2023, that number is expected to drop to one kilogram.

Because their rate of conversion efficiency does not decrease when they are used indoors, in contrast to silicon cells, they are particularly attractive for use in electronic devices such as smart speakers, sensors, and other wearables that may not be exposed to a great deal of actual direct sunlight. This takes advantage of the natural light that is already there, transforming part of it into electrical power and so decreasing the strain placed on tiny batteries and other devices that need charging.

The efficiency rate of 10% leaves a bit to be desired, but these cells may also be utilized for around 20 years, which already dwarfs the lifespans of the already available perovskites (more on that later). When additional companies begin to ramp up production, there is a greater possibility that the costs will be cut in half due to the increased volume of production.

These solar cells may be "printed to order," and they are beginning to make their way into the market on a worldwide scale. This year, German start-up company Heliatek will commence mass production of organic solar cells with the objective of producing 600,000 square meters (with a maximum production capacity of 1.1 million square meters per year!). In addition, the Brazilian firm Sunew is now manufacturing these organic cells. To date, they have produced over 10,000 square meters of organic solar cells specifically for the roofs of vehicles (given their enthusiasm for electric vehicles). Only in December of this past year did the Swedish company Epishine launch their micro solar collecting modules onto the market. These modules tout a rate of energy conversion of 13% and a lifetime of 10 years. These may be used for temperature and humidity control sensors, fire alarms, card readers, and a variety of other gadgets that are often inconspicuous despite the fact that they play a significant role. And then there's Ricoh in Japan, which got its start on a far more modest scale. They only make 100 square meters per year, but that is enough to power 50,000 small smart devices, like wearables and safety sensors in tunnels and bridges.

Even though these cells are amazing, there is still room for improvement, and researchers have found two major breakthroughs that could help organic cells catch that spark.

Put on your seatbelts, because things are about to get quite geeky in here. Let's speak about chirality, shall we?

DNA, along with other compounds that take the form of helices, is classified as chiral. This pattern can be seen all across the natural world, and it plays an essential role in almost all biological processes, from the formation of our genes to photosynthesis. They have an asymmetrical shape, and when electrons go through the structure, they separate the charges that are produced by light (meaning that light can be converted into biochemicals more efficiently).

In most cases, molecules do not deviate from their own structural groups. It's a little bit like being back in high school... (alternating between chiral and achiral, etc.). But scientists at the University of Illinois at Urbana-Champaign found that when they mixed achiral conjugated polymers with a solvent, the solution eventually evaporated, leaving behind reassembled polymers, specifically helixes, which are also called chiral structures.

Moving from achiral structures to chiral structures is a significant step, particularly when considering how to use the concept in the context of organic solar energy. In principle, scientists are able to adapt that chiral structure (and all of the goodness that comes with creating energy that comes along with it) to materials that generally need achiral conjugated polymers to work. Some examples of these materials include solar cells.

Second, let's have a conversation on perfluorinated sulfuric acid ionomers, which is a topic that almost everyone is interested in. (No? Just me?) Permit me to explain: in order to construct fully printable organic solar cells, you need materials that are capable of whole conveyance. That's a void, not a complete You have to have a passion for the English language. In brief, they are referred to as HTMs. The conducting polymer combination of poly(3,4-ethylenedioxythiophene) and polystyrene sulfonate (PEDOT: PSS), which has been shown to be a very promising HTM, has been shown to be a very promising HTM. Although it has been present since the 1990s, it does not live up to expectations in modern times. Unfortunately, it is very acidic and spreads out in water, which could hurt the performance and stability of solar cells made from PEDOT:SS.

Researchers from the Huazhong University of Science and Technology and the Institute of Materials for Electronics and Energy Technology (i-MEET) have developed PEDOT:F, a novel polymer complex that is low in acidity and can be dispersed in alcohol. This was done in an effort to fight this issue. Organic photovoltaics have been found to have a power conversion efficiency of 15% with the use of this novel formula. Also, organic photovoltaics have kept 83% of their original efficiency after being on at full power for a total of 1,330 hours and always being exposed to light.

These recent advances in solar technology may not be the most eye-catching to the ordinary person, but they are undeniable evidence that there is more to come in the field of solar energy in the not too distant future. So, what exactly can we learn from these new advancements, and what does this imply for the industry as a whole?

Record-breaking efficiency and design

First, while it is very thrilling to have broken the global record for solar efficiency, the solar cell design developed by NREL still has its own set of drawbacks. To begin with, the manufacturing of this particular kind of cell will continue to be costly for the foreseeable future. This is an issue that already plagues the renewable energy sector as a whole. It is possible that mass production of cells with this level of efficiency will not be possible for quite some time. If this is the case, we will need to find a way to achieve this goal while maintaining overall costs at a level that will not price major consumers out of the market.

On the other hand, the honeycomb design developed at the University of Surrey appears to be aimed squarely at addressing that issue. The total consumption of silicon by these cells is lower, which results in cost savings throughout the manufacturing process. There is a lot of promise in how we can utilize them as well: while having a textured surface, the film layer is still very thin, which makes them light enough and adaptable enough to travel almost anywhere!

The next thing that has to be done is to start the show rolling by searching for commercial partners and creating production processes. As you may have suspected, that is not an easy task in and of itself, and for the time being, this design is still a long way from the market. Unfortunately, this is the destiny of many promising renewable technologies that are still in the process of being developed.


What about perovskites, which are both the brilliant light of the solar business and its problem child at the same time?

Perovskite cells are now available for purchase, but they are not nearly as efficient as fans had hoped they would be, and they have not even come close to clearing the hurdle that stands in the way of their commercialization. This can be explained in large part by the capricious behavior that they exhibit in the field. Since silicon and perovskite solar cells recently set records for producing more electricity than 25%, the problem is not necessarily one of power. Instead, the problem is one of durability.

Unfortunately, after a few months of usage, perovskite cells in the field lose 10% of their efficiency. It will be difficult to top the performance of silicon cells, whose makers claim that panels will keep 80% of their performance for many, many years; this is because silicon cells have set a high standard. In order for the Solar Energy Technology Office (SETO) to reach its goal of $0.02/kWh by 2030, perovskite cells will have to last at least 20 years in the field.

The last significant obstacle on the path to commercializing perovskite solar panels will most likely be manufacturing. It's kind of a catch-22 situation: we need financing to ramp up production and create cells on a large scale, but financing won't be available until it seems that the scale up will be successful.

The good news is that perovskites do not NEED to outperform silicon cells in order to be competitive. Tandem cells, in which a layer of perovskite is placed on top of a cell made of silicon, are another use for these materials. (We're talking about having the very best of both worlds here!) Because the materials can take in light of different wavelengths, complementary energy harvesting can be done.

Organic cells

So what about cells made of organic matter? The concept in and of itself is still rather appealing. These types of cells could be used pretty much anywhere due to their lightweight and flexible nature. This includes roofs with domes, glass, and other surfaces with odd shapes that couldn't hold the heavier silicon-based panels.

These companies won't be able to power your neighborhood any time soon, but they have made a place for themselves in the market, especially for smaller devices like wearables.

Organic cells

Why are wearables getting so much attention? The vast majority operate on batteries that are only good for a single use and must be changed every one to two years. According to MarketsandMarkets, the worldwide market for smart sensors alone is anticipated to reach $29.6 billion in the year 2026. This is a significant development for this particular sector. Silicon doesn't perform as well inside, and perovskite cells only last a few years at a time, so the current solar technology isn't nearly up to snuff for these more compact applications.

It is true that their overall efficiency rate is not quite up to standard (at least, compared to their other solar counterparts). It is hoped that continued research into chirality and other polymer solutions will, in the long run, help to increase that efficiency rate and make the "printable solar cell" a mainstay in the solar community.

Even though it will most likely be another few years before we see these admittedly cool developments actually make ripples in the market, it is nonetheless a clear sign of the direction in which things are heading. However, if you are thinking about installing solar panels on your roof, you shouldn't wait any longer. Solar panels have improved to the point that they are now capable of meeting a significant portion of the requirements that you likely have for your house. Waiting for the "next great thing" very much guarantees that you will constantly be waiting for it since there is always something better just around the bend. If you reside in the United States, you should take advantage of the current solar tax credit offered by the federal government before it expires at the end of the year. My EnergySage site may assist you in doing research and obtaining estimates from local installers, and you can use it right now. The experience of using EnergySage to study items and select my own installer for my home was fantastic, and I would highly recommend using it. Don't put it off or you'll miss out.

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