Solar energy news and discussion

[weatheriscool]

Researchers create new materials that might increase the stability of perovskite solar cells
https://phys.org/news/2022-09-materials ... cells.html
by Kaunas University of Technology

A group of chemists from Kaunas University of Technology in Lithuania, the developers of numerous breakthrough innovations in the solar energy field, proposed yet another solution to increase the stability and performance of perovskite solar elements. They synthesized a new class of carbazole-based cross-linkable materials, which are resistant to various environmental effects, including strong solvents used in the production of solar cells.

When applied as hole transporting layers, the new materials helped achieve the 16.9% efficiency of the inverted-architecture perovskite cells at the first attempt. It is expected to reach higher efficiency upon optimization.

New materials thermally polymerized to provide resistance

Organic-inorganic hybrid perovskite solar cells have been attracting worldwide attention as a competitive alternative to conventional silicon-based solar technologies. They are cheaper, more flexible and have higher power conversion efficiency. Scientists all over the world are working to solve challenges related to improving the stability and other features of the perovskite solar elements. These layered, new generation solar cells can have two architectonic structures—regular (n-i-p) and inverted (p-i-n) structures. In the latter, the hole transporting materials are deposited under the perovskite absorber layer.

[Yuli Ban]

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A strategy to create more efficient narrow bandgap (NBG) perovskite films for tandem solar cells
https://techxplore.com/news/2022-09-str ... p-nbg.html
by Ingrid Fadelli , Tech Xplore

All-perovskite tandem solar cells, solar cells comprised of stacked wide-bandgap (WBG) and narrow-bandgap (NBG) perovskites, could be particularly promising energy solutions. Compared to other existing photovoltaic systems, these cells could achieve good energy-efficiencies while significantly lowering fabrication costs.

Researchers at University of North Carolina at Chapell Hill and University of Rochester have recently devised a new hot gas-assisted method that could improve the fabrication of NBG perovskite films for tandem solar cells. This strategy combined with an anti-oxidation material added in the film, both of which were introduced in a paper published in Nature Energy, could increase the solar cells' carrier recombination lifetime (i.e., the time it takes for excess charge carriers to decay).

"All-perovskite tandem perovskite solar cells are promising to reduce the cost of photovoltaic systems, due to their potential to reach a much higher efficiency than their single-junction counterparts, while maintaining the solution fabrication processes," Jinsong Huang, one of the researchers who carried out the study, told TechXplore. "Also, compared to single junction perovskite modules, the application of tandem structures, which have much smaller photocurrents but higher photovoltage, can also reduce the cell-to-module efficiency derate, and thus enable the realization of higher module efficiencies for monolithically interconnected modules in a series."

In all-perovskite tandem solar cells, both the WBG and NBG perovskite layers are deposited using a method called blade coating. Blade coating, also known as knife coating or doctor blading, is a scalable coating technique that entails applying an excess of coating material to a substrate and then removing some using a blade, until one reaches the desired coating.

[wjfox]

Todd proposes 400 MW solar farm for New Zealand’s North Island

SEPTEMBER 20, 2022 DAVID CARROLL

New Zealand’s large-scale solar PV market is poised for a momentous shift with energy company Todd Generation pursuing plans to establish a 400 MW solar farm at Rangitāiki on the North Island.

https://www.pv-magazine.com/2022/09/20/ ... th-island/

[Yuli Ban]

This week, the US Department of Energy's Berkeley Lab released its annual analysis of solar energy in the US. It found that nearly half the generating capacity was installed in the US during 2021 and is poised to dominate future installs. That's in part because costs have dropped by more than 75 percent since 2010; it's now often cheaper to build and operate a solar plant than it is to simply buy fuel for an existing natural gas plant.

The analysis was performed before the passage of the Inflation Reduction Act, which contains many incentives and tax breaks that should expand solar's advantages in the coming years.

In terms of large, utility-scale solar installs, the US added over 12.5 gigawatts of new capacity last year, bringing the total installed capacity to over 50 gigawatts. Texas led the way, with about a third of the total capacity added (3.9 GW) going online in the Lone Star State. Combined with residential and other distributed solar installations, solar alone accounted for 45 percent of the new generating capacity added to the grid last year.

[weatheriscool]

First single-crystal organometallic perovskite optical fibers
https://phys.org/news/2022-09-single-cr ... ibers.html
by Queen Mary, University of London

Due to their very high efficiency in transporting electric charges from light, perovskites are known as the next generation material for solar panels and LED displays. A team led by Dr. Lei Su at Queen Mary University of London now have invented a brand-new application of perovskites as optical fibers. The results are published in Science Advances.

Optical fibers are tiny wires as thin as a human hair, in which light travels at a superfast speed—100 times faster than electrons in cables. These tiny optical fibers transmit the majority of our internet data. At present, most optical fibers are made of glass. The perovskite optical fiber made by Dr. Su's team consists of just one piece of a perovskite crystal. The optical fibers have a core width as low as 50 μm (the size of a human hair) and are very flexible—they can be bent to a radius of 3.5 mm

Compared to their polycrystal counterparts, single-crystal organometallic perovskites are more stable, more efficient, more durable and have fewer defects. Scientists have therefore been seeking to make single-crystal perovskite optical fibers that can bring this high efficiency to fiber optics.

Dr. Su, Reader in Photonics at Queen Mary University of London, said, "Single-crystal perovskite fibers could be integrated into current fiber-optical networks, to substitute key components in this system—for example in more efficient lasing and energy conversions, improving the speed and quality of our broadband networks."

Dr. Su's team were able to grow and precisely control the length and diameter of single-crystal organometallic perovskite fibers in liquid solution (which is very cheap to run) by using a new temperature growth method. They gradually changed the heating position, line contact and temperature during the process to ensure continuous growth in the length while preventing random growth in the width. With their method, the length of the fiber can be controlled, and the cross section of the perovskite fiber core can be varied.

[wjfox]

Romania could soon house Europe’s largest photovoltaic park

By Bogdan Neagu | EURACTIV
6:04 (updated: 9:39)

Independent clean energy producer Rezolv Energy has acquired the rights to build and operate a 1,044 Megawatt solar photovoltaic plant in western Romania, which, if constructed, is expected to become Europe’s largest solar PV plant.

Rezolv Energy, which acquired the rights from the Monsson Group, is investing in around 1.6 million new solar panels expected to generate about 1,500,000 Megawatt-hour (Mwh) a year capable of powering more than 370,000 households.

The project is already in the late-stage development phase, and Rezolv Energy is already appraising technology solutions and debt financing options.

Construction is due to start in the first half of next year, meaning the plant should be online by 2025.

https://www.euractiv.com/section/energy ... taic-park/

[wjfox]

[weatheriscool]

New insights into energy loss open doors for up-and-coming solar tech
https://techxplore.com/news/2022-11-ins ... oming.html
by Princeton University

Organic solar cells are an emerging technology with a lot of promise. Unlike the ubiquitous silicon solar panel, they have the potential to be lightweight, flexible, and present a variety of colors, making them particularly attractive for urban or façade applications. However, continued advancements in device performance have been sluggish as researchers work to understand the fundamental processes underlying how organic solar cells operate.

Now, engineers at Princeton University and King Abdullah University of Science and Technology have described a new way to express energy loss in organic solar cells and have extended that description to make recommendations for engineering the best devices. This breakthrough could reimagine the conventional approach to constructing organic solar cells. Their work was published on November 18 in Joule.

"There was a way that energy loss in organic solar cells was traditionally described and defined. And it turns out that that description was not wholly correct," said Barry Rand, co-author of the study and associate professor of electrical and computer engineering and the Andlinger Center for Energy and the Environment.

[weatheriscool]

Researchers optimize performance and stability of multi-layer organic solar cells
https://techxplore.com/news/2022-11-opt ... cells.html
by Friedrich–Alexander University Erlangen–Nurnberg

Acceptor layers made of oligomers can increase the performance of organic solar cells and ensure a long operating life at the same time. This is the result of a series of complex laboratory experiments conducted by materials scientists at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU). Organic solar cells are less complex to manufacture than conventional silicon modules and are considerably more versatile as they can be flexible and transparent. The researchers' findings have been published in the journal Nature Energy.

The war in Ukraine continues to serve as a stark reminder of how important it is for us to cease our dependency on fossil fuels as quickly as possible. The rapid expansion of regenerative energy sources is one of the keys to success in this respect. In the case of photovoltaics, for example, the difficulties not only involve the struggle for higher output, but also the development of new applications as the surface area available for solar panels is limited in densely-populated industrial nations such as Germany.

This is the reason why so much research is currently being carried out on organic photovoltaics. In contrast to the silicon used in conventional systems, organic solar cells consist of carbon-based semi-conductors that are directly applied from a solution onto a supporting film. This means the modules are flexible and can be translucent or completely transparent, which opens up a wide range of potential applications in urban spaces, including use in window panes.

[wjfox]

[Rachellewinegar]

Building efficient and thermally stable perovskite solar cells using Ti₃C₂TₓMXene

by University of Queensland
Credit: University of Queensland

A new generation of cheap, sustainable and efficient solar cells is a step closer, thanks to scientists at The University of Queensland.

Researchers at UQ's Australian Institute for Bioengineering and Nanotechnology (AIBN) modified a nanomaterial to make solar cells as efficient as silicon-based cells, but without their high cost and complex manufacturing.

Professor Joe Shapter said the finding addressed an urgent need for alternative environmentally friendly energy sources capable of providing efficient and reliable energy production.

"Silicon-based solar cells remain the dominant first-generation product making up 90 percent of the market, but demand was high for cells that could be manufactured without their high prices and complexity," Professor Shapter said.

"Among the next-generation technologies, perovskite solar cells (PSCs) have attracted enormous attention because of their high efficiency and ease of fabrication.

"The technology has undergone unprecedented rapid development in recent years.

"But the new generation of solar cells still have some drawbacks such as poor long-term stability, lead toxicity and high material costs."

Professor Shapter said his team studied a nanomaterial that showed great promise in overcoming some of the new cell's drawbacks and used doping, a common method of modifying the new cell's nanomaterial to enhance its electrical properties.

https://techxplore.com/news/2021-10-eff ... solar.html

If I understand correctly, however, is it possible to receive solar energy without doing any damage to nature?

[weatheriscool]

Researchers unveil multi-mode reactions in perovskite solar cells
https://techxplore.com/news/2022-11-unv ... solar.html
by Liu Jia, Chinese Academy of Sciences

As a promising photovoltaic material, metal halide perovskite yields high efficiency in solar cells. However, the deep-level traps of minority carriers at the surface of the p-i-n perovskite solar cells can suppress nonradiative recombination. The precise passivation of deep-level traps has been a major focus in raising the power conversion efficiency (PCE) to the theoretical Shockley-Queisser limit.

Recently, a research group led by Prof. Xu Jixian and Prof. Wu Xiaojun from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS), and their collaborators from Suzhou Institute of Nano-Tech and Nano-Bionics of CAS revealed the perovskite/polymer multi-mode interactions and their correlation with the passivation of the deep-level traps, and discovered a new in-situ protonation process that significantly reduces the deep-level traps of minority carriers. This work was published in Joule.

Previously known interaction modes at the perovskite/polyethyleneimine (PEI) interface include conventional physisorption and metal-chelation, which either shows minor passivation effects or tends to passivate the majority carrier traps. To overcome these problems, the researchers used high-sensitivity X-ray photoelectron spectroscopy (XPS) and sum-frequency-generation spectroscopy to identify in-situ protonation process of the amine group at the perovskite/PEI surface.

[weatheriscool]

Researchers realize perovskite-based phase heterojunction solar cells
https://techxplore.com/news/2022-11-per ... cells.html
by Ingrid Fadelli , Tech Xplore

Over the past few decades, engineers and material scientists have created increasingly advanced and efficient solar technologies. Some of these technologies are based on photovoltaics with a so-called heterojunction structure, which entails the integration of two materials with distinct optoelectronic properties.

Researchers at Technische Universität Dresden have recently realized a different type of solar cells, referred to as phase heterojunction (PHJ) solar cells. These cells, introduced in a paper published in Nature Energy, were fabricated using two polymorphs (i.e., structural forms) of the same material, the perovskite CsPbI3, instead of two entirely different semiconductors.

"The realization of a PHJ requires the ability to fabricate two different phases of the same perovskite composition on top of each other," Yana Vaynzof, lead author of the paper, told TechXplore. "While the fabrication of 𝛽-phase CsPbI3 perovskite by solution-processing is well established in the literature, we needed to develop a method to deposit a 𝛾-phase perovskite without dissolving the underlying 𝛽-phase layer, so we decided to use thermal evaporation for this purpose."

In one of their previous studies, Vaynzof and her team devised a strategy to evaporate 𝛾-phase CsPbI3 perovskites by heating them. This strategy proved to be crucial for the experimental realization of their new PHJ solar cells.

[weatheriscool]

Can a new technique for capturing 'hot' electrons make solar cells more efficient?
https://phys.org/news/2022-12-technique ... solar.html
by Vittoria D'Alessio, University of Bath

A new way of extracting quantitative information from state-of-the-art single molecule experiments has been developed by physicists at the University of Bath. Using this quantitative information, the researchers will be able to probe the ultra-fast physics of "hot" electrons on surfaces—the same physics that governs and limits the efficacy of silicon-based solar cells.

Solar cells work by converting light into electrons, whose energy can be collected and harvested. A hot solar cell is a novel type of cell that converts sunlight to electricity more efficiently than conventional solar cells. However, the efficiency of this process is limited by the creation of energetic, or "hot," electrons that are extremely short lived and lose most of their energy to their surrounding within the first few femtoseconds of their creation (1 femtosecond equals 1/1,000,000,000,000,000 of a second).

The ultra-short lifetime of hot electrons and the corresponding short distance they can travel mean probing and influencing the properties of hot electrons is experimentally challenging. To date, there have been a few techniques capable of circumventing these challenges, but none has proven capable of spatial resolution—meaning, they can't tell us about the crucial connection between a material's atomic structure and the dynamics of hot electrons within that material.

Manipulating a target

The researchers from Bath's Department of Physics studied hot electrons using a scanning tunneling microscope (STM). This device is designed to image individual atoms and molecules. By injecting a small electrical current (a beam of hot electrons) into a single target molecule, the device can also manipulate a target—moving it, rotating it, breaking a chemical bond or making a new chemical bond.

[weatheriscool]

Paper-thin solar cell can turn any surface into a power source
https://techxplore.com/news/2022-12-pap ... power.html
by Adam Zewe, Massachusetts Institute of Technology

MIT engineers have developed ultralight fabric solar cells that can quickly and easily turn any surface into a power source.

These durable, flexible solar cells, which are much thinner than a human hair, are glued to a strong, lightweight fabric, making them easy to install on a fixed surface. They can provide energy on the go as a wearable power fabric or be transported and rapidly deployed in remote locations for assistance in emergencies. They are one-hundredth the weight of conventional solar panels, generate 18 times more power-per-kilogram, and are made from semiconducting inks using printing processes that can be scaled in the future to large-area manufacturing.

Because they are so thin and lightweight, these solar cells can be laminated onto many different surfaces. For instance, they could be integrated onto the sails of a boat to provide power while at sea, adhered onto tents and tarps that are deployed in disaster recovery operations, or applied onto the wings of drones to extend their flying range. This lightweight solar technology can be easily integrated into built environments with minimal installation needs.

"The metrics used to evaluate a new solar cell technology are typically limited to their power conversion efficiency and their cost in dollars-per-watt. Just as important is integrability—the ease with which the new technology can be adapted. The lightweight solar fabrics enable integrability, providing impetus for the current work. We strive to accelerate solar adoption, given the present urgent need to deploy new carbon-free sources of energy," says Vladimir Bulović, the Fariborz Maseeh Chair in Emerging Technology, leader of the Organic and Nanostructured Electronics Laboratory (ONE Lab), director of MIT.nano, and senior author of a new paper describing the work.

Joining Bulović on the paper are co-lead authors Mayuran Saravanapavanantham, an electrical engineering and computer science graduate student at MIT; and Jeremiah Mwaura, a research scientist in the MIT Research Laboratory of Electronics. The research is published today in Small Methods.

[wjfox]

[weatheriscool]

Korean firm plans $2.5B in new solar panel plants in Georgia
Source: AP

By JEFF AMY an hour ago

ATLANTA (AP) — A South Korean solar panel maker will invest more than $2.5 billion to build factories in Georgia, hiring 2,500 new employees and making components usually manufactured outside the United States, the company announced Wednesday.

Qcells, a unit of Hanwha Solutions, will build a new factory in Cartersville that will employ 2,000 people, with construction starting within weeks and production starting before the end of 2024.

The company also announced a third phase of its Dalton plant, already the largest maker of solar panels in the Western Hemisphere. Qcells will add nearly 500 jobs in Dalton, raising employment above 1,500 once all expansions are complete there.

“We are seeking to further expand our low-carbon solar investments as we lead the industry towards fully American-made clean energy solutions,” Qcells CEO Justin Lee said in a statement.

Read more: https://apnews.com/article/biden-busine ... f789e3174a

[weatheriscool]

Stability of perovskite solar cells reaches next milestone
https://techxplore.com/news/2023-01-sta ... stone.html
by Helmholtz Association of German Research Centres

Perovskite semiconductors promise highly efficient and low-cost solar cells. However, the semi-organic material is very sensitive to temperature differences, which can quickly lead to fatigue damage in normal outdoor use. Adding a dipolar polymer compound to the precursor perovskite solution helps to counteract this.

This has now been shown in a study published in the journal Science by an international team led by Antonio Abate, HZB. The solar cells produced in this way achieve efficiencies of well above 24 %, which hardly drop under rapid temperature fluctuations between -60 and +80 Celsius over one hundred cycles. That corresponds to about one year of outdoor use.

The material class of halide perovskites is seen as a great hope for even more solar power at even lower costs. The materials are very cheap, can be processed into thin films with minimal energy input and achieve efficiencies that are significantly higher than those of conventional silicon solar cells.

[weatheriscool]

Majority of Texans back shift to solar energy

by Rashda Khan, University of Houston
https://techxplore.com/news/2023-02-maj ... nergy.html

Two years after Winter Storm Uri wreaked havoc on Texas' power grid, a majority of Texans support expanding the country's reliance on solar and other alternative sources of energy, according to the most recent survey report released by the Hobby School of Public Affairs at the University of Houston.

While 64% of Texans favor expanding U.S. reliance on solar power plants, 59% favor reliance on geothermal plants and 57% favor reliance on wind turbine farms.

In comparison, 42% favored increasing reliance on nuclear power plants and natural gas-fired power plants. The majority of the 41% who preferred expanding U.S. reliance on onshore conventional oil and gas came from the Boomer/Silent Generation.

Texans also overwhelmingly (90%) supported net-metering legislation that would allow homes and businesses with solar panels to sell any extra power they generate back to the electric grid for the same price that the utility charges consumers to buy the electricity. And 82% supported tax incentives for homeowners and businesses to install rooftop solar panels and battery storage.