Over the past decade, illuminating gillnets with LED lights or chemical lightsticks has emerged as a promising solution to reduce sea turtle bycatch while maintaining target fish catch across multiple ocean basins. However, LED lights require replaceable batteries, and chemical lightsticks only last 24 h, leading to recurring operational costs for fishers and concerns over battery and lightstick disposal. To overcome these challenges, we developed a light that (1) harnesses solar energy to illuminate gillnets; (2) flashes at a duty cycle optimized for power consumption under different fishing durations; and (3) is designed to function as a buoy, providing easy integration of the technology into existing fishing gear. Controlled fishery experiments in Mexico's Gulf of California revealed that solar-powered illuminated nets significantly reduced predicted mean sea turtle bycatch rates by 63% while maintaining target fish catch. These results suggest that fisheries bycatch can be mitigated by harnessing energy from the sun, representing a novel and renewable bycatch reduction technology with potential for global applicability.

As photovoltaic (PV) systems become a larger fraction of the electricity supply, use of expanded weather datasets for PV system modeling becomes increasingly important. Particularly, a report from the Energy Systems Integration Group explicitly stated this need for power system planning and solar energy modeling. In this paper, we focus on two weather related datasets, namely, rainfall and air quality. Such datasets are needed for accurate PV system models including self-cleaning and soiling calculations, and more specifically for modeling agrivoltaic systems, which integrate crop and solar production. We demonstrate the integration of multiple types of datasets, including National Oceanic and Atmospheric Administration precipitation data and Environmental Protection Agency air particulate matter concentration data. The results show that the different datasets greatly impact the PV system soling losses, and thereby influence overall PV production calculations.

Ultra-thin silicon space solar cells leverage the advantages from silicon' dominance in the terrestrial market and develop high efficiency, lightweight, flexible, and radiation hard silicon solar cells. A thin Si solar cell can reduce the cost of space photovoltaics by a factor of 20X to more than 50X in larger scale production, while closely matching or exceeding the specific power, efficiency, and end-of-life to beginning-of-life efficiency. The realization of radiation hard silicon space cells relies on on thin solar cells, in which the thickness is less than the stopping distance of radiation in the device, substantially changing the type and nature of defects in the silicon solar cells. Experimental results show that a thin solar cell allows recovery of radiation damage under operating conditions, and modeling shows that a thin space solar cell can achieve efficiencies of 20 to 23% and up to 25% with novel light trapping.

Achieving 50% efficient solar cells is typically considered well outside the possibility for a single-junction silicon photovoltaic solar cell, particularly a commercial silicon solar cell. The goal of this paper is to show that a combination of innovations can put silicon solar cells on a path to 50% efficiency using physical processes that have been physically observed but not optimized in structures consistent with commercial solar cells. A central feature of an ultra-high efficiency solar cell, and a critical challenge in making such devices, is the need for very thin solar cells below 10 microns. An ultra-thin solar cell allows the incorporation of other innovations, giving efficiencies approaching 50% using conventional physics and structures. Ultra-thin solar cells, in combination with other physical processes, such as nanostructured light trapping, allow new processes and further increase possible efficiencies. Overall, innovations include limited acceptance angles, low concentration, and effective light trapping, leading to an efficiency potential of 36% without sacrificing yearly energy generation. Adding the extraction of carriers at the quasi-Fermi level rather than the Fermi level and two-carrier generation gives an efficiency of up to 51%.

Achieving 50% efficient solar cells is typically considered well outside the possibility for a single-junction silicon photovoltaic solar cell, particularly a commercial silicon solar cell. The goal of this paper is to show that a combination of innovations can put silicon solar cells on a path to 50% efficiency using physical processes that have been physically observed but not optimized in structures consistent with commercial solar cells. A central feature of an ultra-high efficiency solar cell, and a critical challenge in making such devices, is the need for very thin solar cells below 10 microns. An ultra-thin solar cell allows the incorporation of other innovations, giving efficiencies approaching 50% using conventional physics and structures. Ultra-thin solar cells, in combination with other physical processes, such as nanostructured light trapping, allow new processes and further increase possible efficiencies. Overall, innovations include limited acceptance angles, low concentration, and effective light trapping, leading to an efficiency potential of 36% without sacrificing yearly energy generation. Adding the extraction of carriers at the quasi-Fermi level rather than the Fermi level and two-carrier generation gives an efficiency of up to 51%.

The importance of semiconductor industries necessitates a corresponding focus on developing students to advance the industry. It is recognized that there is a difficulty in transitioning new approaches from the laboratory to fabrication (lab-to-fab). A production environment has extensive inter-relation between different processes. Moreover, the success of a production environment relies on concepts of yield and optimization of a process for large-scale production, which are not typically introduced or used in most university research environments. Further, the lack of access to large-scale data means that the use of statistical design tools is done using either "made-up" data or examples from other industries. Important, students cannot design an experiment in the courses, testing their statistical design or understanding by changing parameters and examining the outputs. A virtual production line for solar cells, initially developed by UNSW and with Jeff Cotter, enables complex processing to be taught via simulatoins.

Climate changes and its many associated impacts are one of the most critical global challenges. Photovoltaics has been instrumental in mitigation of CO2 through the generation of low carbon electricity. However, the goal of limiting global warming to 1.5 degrees C increasingly requires additional approaches. The paper presents how PV surfaces can be designed to reverse the Earth's radiative imbalance from increasing atmospheric greenhouse gases which cause higher global temperatures. The new PV surfaces generate electricity, reflect sub-band gap radiation, minimize their temperature, generate thermal radiation and emit additional IR through the atmosphere. The key results are: (1) It is thermodynamically possible to reverse global temperature rise through the large-scale deployment of solar converters without requiring an increase in area compared to that predicted necessary for meeting clean electricity generation; (2) There is substantial scope in the properties of the solar converters that are deployed depending on where they are deployed (e.g., the albedo and emissivity of their surroundings); (3) The inclusion of reversing global warming as a goal for solar converters increases the need for high efficiency, radiatively efficient solar cells.

Degradation due to acetic acid in photovoltaic (PV) modules has been a commonly observed phenomenon for both damp-heat exposure and outdoor operations. Acetic acid is a degradation byproduct of ethylene -vinyl acetate (EVA), a common module encapsulant. To address this issue, robust metallization pastes and cell technologies are being developed. However, it is important to assess how these technologies perform in an acetic acid environment and withstand degradation before they are implemented in the solar market. In this work, we investigate the impact of acetic acid exposure on four different cell groups: monofacial passivated emitter and rear contact (PERC) cells with advanced telluride-based front contact pastes, bifacial PERC cells with novel aluminum rear contact pastes, bifacial tunnel oxide passivated contacts (TOPCon) cells, and silicon heterojunction (SHJ) cells. These cells were exposed to acetic acid for different time increments. The recombination losses were characterized by Suns-VOC, and multi-variate regression analysis of intensity -dependent photoluminescence (PL) images with Griddler AI. Resistive losses were tracked with the transmission line method (TLM). Samples showing severe performance degradation were selected for further materials characterization to understand the root cause. Top-down and cross-sectional scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS) were performed to investigate the change in materials properties. Our study shows that the front contacts of the bifacial TOPCon cells and monofacial PERC cells were significantly affected by acetic acid exposure. The SHJ cells were found to be the most stable.

The need for low-cost ultra-radiation hard PV technological solution is becoming extremely important with the ongoing space conquest adventure. In this article we focus on the novel feature of recently developed ultra-thin silicon solar cell - incorporate proprietary defect-engineered technology - to self-cure radiation damage, resulting in a minimal loss of efficiency over a cell operational lifetime.

Recently, the significant improvements in the surface and contact passivation of silicon (Si) solar cells as well as their bulk quality have shifted their operating point to higher injections. Hence, they are less dependent on wafer doping. This shift opens an opportunity of using high-resistivity wafers for practical photovoltaic applications, introducing a promising approach to push the cell efficiency towards the intrinsic limit and to improve the module reliability by increasing the cell breakdown voltage. Therefore, insights into the performance of Si solar cells using high-resistivity wafers at various operating temperatures are of significant interest. In this study, we investigate the temperature- and illumination-dependent performance of Si heterojunction (SHJ) solar cells using a wide range of wafer resistivities (between 3 and 1000 Omega center dot cm). Although a reduction in the passivation quality of the passivating contacts is observed at elevated temperature, the impact on the temperature coefficient of the open-circuit voltage (TCVoc)-the dominant contributor to the temperature coefficient (TC) of the cell efficiency-is very limited. Their TCVoc are still dominated by the temperature dependence of the effective intrinsic carrier concentration. Furthermore, we also find that the investigated cells are more sensitive to temperature variation at lower illumination intensities. It is noteworthy that the efficiency of the cells fabricated using high-resistivity wafers is comparable to that of the reference cells at any given temperature, highlighting the potential of using high-resistivity wafers for solar cells.

As we design solar cells with better surface passivation, it is important to revisit the bulk properties. The use of lightly doped wafers provides a promising way to mitigate Auger recombination and increase the breakdown voltage of solar cells, which could lead to new module and system designs. Thus, studying the performance of silicon (Si) solar cells and modules using such wafers in relevant field conditions is of significant interest. In this study, we experimentally investigate the impact of the bulk resistivity (up to >15,000 Ω.cm) on the properties of Si heterojunction solar cells under different illuminations (0.1-1 suns) and temperatures (25–70 °C). We also study the dependency between the breakdown voltage and the bulk resistivity. The results indicate that for very low illuminations intensities down to 0.1 suns, cells with very high bulk resistivities, over 15,000 Ω·cm, have comparable performances to cells with much lower bulk resistivities. The temperature coefficients measured on these cells are also comparable with values previously reported for cells using wafers with standard resistivities. The cells with bulk resistivities over 1,000 Ω.cm show breakdown voltages larger than -1,000 V, almost two orders of magnitude higher than in typical Si solar cells. Our simulations indicate that in the absence of bypass diodes, shaded solar cells with larger breakdown voltages still operate in forward-bias, even under extreme shading conditions, protecting the integrity of the cell and module. Together, these results highlight the large potential of using high-resistivity wafers to manufacture high-efficiency Si solar cells suitable to operate under relevant field conditions, and with the prospect of more robust and cost-effective module designs.

This paper presents a model for PV education that brings together photovoltaics engineers with 6 th -12 th -grade students and teachers to test agrivoltaics applications using citizen science. A summer research experience program engaged high school students in building a novel agrivoltaics school garden monitoring system, facilitated by PV engineering researchers and education scholars. The high schoolers are mentoring middle grade students as they design and install school gardens and collect data on garden conditions with and without solar panels covering crops. Ideas for multi-generational collaboration are explored.

Climate changes and its many associated impacts are one of the most critical global challenges. Photovoltaics has been instrumental in mitigation of CO2 through the generation of electricity. However, the goal of limiting global warming to ${1.5^{\circ}\mathrm{C}}$ increasingly requires additional approaches. The paper presents how PV surfaces can be designed to reverse the Earth' radiative imbalance from increased greenhouse gasses that lead to higher global temperatures. The new PV surface generate electricity, reflect sub-band gap radiation, minimize their temperature, generate thermal radiation and emit additional IR through the atmospheric, with these processes totaling ${650 \mathrm{W}/\mathrm{m}^{2}}$ . This is realized by: (1) PV system efficiency at operating temperature> 20% and sub-band gap reflection of ${150 \mathrm{W}/\mathrm{m}^{2}}$ for a total of ${350 \mathrm{W}/\mathrm{m}^{2};}$ (2) Thermally emitted radiation (radiative cooling) of 150 ${\mathrm{W}/\mathrm{m}^{2};}$ and (3) Active IR emission through an atmospheric window at 1.5 mm of ${150 \mathrm{W}/\mathrm{m}^{2}}$ . With such PV surfaces, we show that 10 TW of installed PV can reverse global warming. Using PV to balance global temperatures introduces additional considerations for PV, focusing on high efficiency, particularly high efficiency at operating temperatures, radiative cooling, and new processes for 1.5 mm emission. We find that depending on their design, PV panels can increase or decrease global temperatures.

The cumulative installed capacity of photovoltaics has passed 1 TW, of which about two-thirds were only installed in the past five years. Many of these new installations incorporate novel module and cell designs that have not yet been subjected to long-term in-field characterization. Indoor accelerated stress testing has historically been a valuable methodology to identify fault mechanisms, estimate degradation rates, and to ensure the safety and normal operation of modules in the field. Still, these methodologies deliver an incomplete image of the exact stress mechanisms that photovoltaic systems are subject to outdoors, which vary with location, time of day, and time of year. In this work we review different outdoor methods to measure current–voltage (I–V) characteristics of photovoltaic systems, discuss how the environmental conditions impact those characteristics, and examine alternative methodologies for acquiring light and pseudo I–V characteristics more applicable to larger scale installations. This review also provides an insight into methods useful for real-time monitoring and degradation analysis at the module and string level.

The paper presents experimental results on agrivoltaics and an optimized optical design. We show: (1) The water utilization benefit of an agrivoltaic module on crops could be quantified, which is the first time this is demonstrated in agrivoltaic literature; (2) Simultaneous benefits were observed across a range of different crops and impacts were compared on these different crops, which is also the first time this is demonstrated in agrivoltaic literature; (3) Optimal light for plants requires full sun early in the day and shade later in the day; (4) An optical design for the module achieves a light profile which also produces electrical generation that is comparable with conventional PV solar modules.

Larger solar cells are preferred for higher power output. However, they produce higher current and lead to higher ohmic loss. This loss has prompted manufacturers to laser cut cells into halved cells, resulting in lower current, higher voltage string‐cells. While these techniques reduce ohmic loss, they introduce cutting‐edge recombination. The monolithic solar cell resembles halved cell but without requiring cutting the original cell into strings of cells which saved the cutting‐edge recombination loss. However, we observed that the interconnection of base regions of the string‐cells on the same wafer leads to problems such as lateral forward bias current, resulting in severe degradation of the fill factor (FF) and open‐circuit voltage ( V OC ). Solutions to these issues are proposed including depassivated surfaces between string‐cells, optimized spacing between the string‐cells, lowered base doping density, thinner wafers, and shading regions between the string‐cells. According to simulation results, these methods could increase the efficiency of the monolithic cell to very close to the baseline cell. With the consideration of the reduced shading, ohmic loss, and module blank areas on the cell‐to‐module process, the efficiency of a module with monolithic cells could exceed that of a module with baseline cells or a module of halved/shingling cells.

Plated copper (Cu) contacts for silicon (Si) solar cells are an attractive alternative material to conventional screenprinted silver, but there are unresolved questions on the long-term integrity of plated contact structures. In this work, we perform characterization on plated Cu contacts from encapsulated cells that were degraded during extended exposure to damp heat (DH) stress. First, using energy-dispersive X-ray spectroscopy, we find evidence of Cu outdiffusion upward through capping layers made of both tin and silver applied with light-induced plating, resulting in a layer of Cu on the outer contact surface. We hypothesize that if Cu is mobile in the module, it may eventually find some route by which to enter the Si cells where it can degrade performance. Subsequently, in several types of Cu-plated, DH-degraded cells, secondary ion mass spectrometry detects elevated levels of Cu at the Si surface and in the Si cell bulk, which suggests that Cu can indeed migrate from contacts into Si over the course of DH stress.

Solar cells industries have a trend of making larger wafers, which leads to larger ohmic loss. Halved and shingling cells possess advantages, such as lower ohmic and shading loss, which gives them an advantage over normal solar cells. Monolithic cell resembles halved and shingling cells but without the necessity to cut original cells into strings of smaller cells. The monolithic cell has multiple string cells on the same wafer interconnected with fingers front‐to‐front and back‐to‐back. As a result, the monolithic cell possesses the same advantages while eliminating the cutting‐edge recombination loss. The disadvantage of the monolithic cell is the extra loss caused by the unseparated base region of string cells. In previous studies, efforts have been devoted to reducing this loss by increasing the internal resistance between string cells. In this paper, a quantitative analysis is proposed. It provides means to calculate the effect of different parameters on the extra power loss. Under this guideline, the theoretical minimum extra efficiency loss can also be obtained through directional optimization. As a result, the loss due to the interconnected base region can be further reduced from 1.5% absolute (1.5% abs ) to less than 0.6% abs .

Recent developments in industry on surface passivation open the possibility of using less doped substrates in silicon solar cells. We investigate how the bulk resistivity affects the performance of silicon cells and the reliability of modules. Herein, n‐ and p‐type silicon heterojunction cells with bulk resistivities between 3 and 15 000 Ωcm are studied. We measure the current–voltage characteristics of n‐type cells across the resistivity range, and we find comparable responses to illumination intensities between 0.1 and 1 suns. The cells with bulk resistivities over 1000 Ωcm show breakdown voltages larger than −1000 V, almost two orders of magnitude higher than in typical commercial cells. Although modules have bypass‐diodes to prevent cells from going into breakdown, higher breakdown voltages can improve the reliability of modules in case of bypass‐diode failure and reduce the module cost by easing the number of bypass‐diodes required. Finally, the cells have been submitted to light soaking. The float‐zone p‐type cells with bulk resistivities over 10 000 Ωcm are less sensitive to light‐induced degradation than cells with bulk resistivities below 10 Ωcm. The former show to recover few hours after light soaking, while the latter recover only after dark annealing.

Electric utility rate plans are becoming more complex, making it increasingly difficult to calculate the cost of electricity for residential users. This masks the costs and benefits of residential solar and solar + batteries and sends incorrect price signals to consumers. To our knowledge, the impacts of the costs of complex rate plans on the LCOE of solar and batteries for residential consumers has not been calculated and presented. This paper calculates the LCOE for combinations of solar and batteries, including no solar and/or batteries, examining the impact of effects such as time of use and demand charges. The key results are that more complex rate plans show little economic benefit for solar and battery users and continue to exacerbate the problems (commonly referred to as the "duck curve") which is often given as the main roadblock to renewable expansion. These results are primarily due to electricity charges not directly related to overall energy use. There is an increasing component of fixed charges (either solar-related or applicable to all users), such that reducing the electricity usage from the grid with lower-cost solar electricity does not substantially reduce overall LCOE. These fixed charges also substantially increase the LCOE for smaller electrical loads, in some cases nearly doubling it. The second type of electricity charge giving high rates is a demand charge. For demand charges, eliminating every peak is not feasible, such that the charges from the utility are essentially constant. In addition to discouraging the use of solar, these plans negatively impact the utility, as batteries in residential systems have a beneficial impact on both consumers and utilities, enabling reductions in electricity use during early evening by more than 80%.