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Repulsion of dust by electrostatic charge induction. (A) Dust particles spread on the bottom metallic electrode are observed to repel on application of voltage (~12 kV) between the plates separated by ~1.5 cm. Particles have an average density of 2.6 g/cm 3 and consists of up to 77% silica. (B) The electrostatic repulsion results from charging by induction, where charge of same polarity as that of the contacting electrode accumulates on the dust particle. (C) The behavior of dust particles is similar to that of conductive iron particles where particle liftoff happens when the applied voltage reaches a threshold value that enables particles to overcome the force that adhere them on to the surface.
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Dust accumulation on solar panels is a major challenge, as it blocks a large portion of sunlight. Solar panels are therefore cleaned regularly using large quantities of pure water. Consumption of water for cleaning, especially in deserts, poses a substantial sustainability challenge. Here, we present a waterless approach for dust removal from solar...
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... approach to "actively charge" dust particles and impart strong Coulombic force for dust repulsion. Our approach overcomes the prior limitations that occur due to reliance on relatively weak, short-range dielectrophoretic/ triboelectric force and eliminates the issue of electrical shorting. Our work was motivated by the experiment shown in Fig. 2A, where we observed that dust particles resting on the bottom electrode in a parallel plate setup are repelled from the surface on application of sufficient voltage (movie S1). This occurs because of induction that causes charge accumulation on the dust, as shown in the schematic of Fig. 2B. When we performed similar experiments by ...
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... Our work was motivated by the experiment shown in Fig. 2A, where we observed that dust particles resting on the bottom electrode in a parallel plate setup are repelled from the surface on application of sufficient voltage (movie S1). This occurs because of induction that causes charge accumulation on the dust, as shown in the schematic of Fig. 2B. When we performed similar experiments by replacing dust particles with conductive iron or insulating Teflon particles, we observed that dust particles qualitatively behaved like iron rather than Teflon. Both dust and iron particle liftoff ( fig. S1) are removed from the electrode surface when the applied voltage exceeds certain ...
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... similar experiments by replacing dust particles with conductive iron or insulating Teflon particles, we observed that dust particles qualitatively behaved like iron rather than Teflon. Both dust and iron particle liftoff ( fig. S1) are removed from the electrode surface when the applied voltage exceeds certain threshold value as shown in Fig. ...
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... control parameter, we systematically study the electrostatic dust removal process. As shown in the free body diagram of a dust particle (Fig. 3A), the electrostatic force (F E ) acting to remove the particle from the surface is opposed by the forces of adhesion (F A ) and gravity (F G ) that tend to keep the particle on the surface. As shown in Fig. 2C, the presence of a critical threshold voltage shows that the particle lifts off from the surface when charge induction results in a strong enough electrostatic repulsive force to overcome adhesion and ...
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... than in the bulk volume of the particle, similar to conducting materials (46). Last, to compare the magnitude of charge on dust particles with that of particles of known electrical conductivity , we performed silicone oil bath experiments using Teflon ( ~ 10 −24 S _ m , good insulator) and steel ( ~ 10 6 S _ m , good conductor) spheres ( fig. S2). While Teflon particles remained stationary at the bottom electrode indicating negligible charge induction, steel particles bounced between the electrodes similar to dust particles. We estimate the charge Q using force balance. We define a nondimensional charge (Q*) based on the experimentally estimated charge and the theoretical ...
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Solar panels often suffer from dust accumulation, significantly reducing their output, especially in desert regions where many of the world's largest solar plants are located. Here, an autonomous dust removal system for solar panels, powered by a wind‐driven rotary electret generator is proposed. The generator applies a high voltage between one sol...
Citations
... This process involves the transfer of charges, leading to the accumulation of charges of different polarities and densities on the surface of objects, resulting in electrostatic effects. Although static electricity plays a positive role in various fields such as electrostatic dust removal [6][7][8][9], electrostatic spraying [10][11][12][13], electrostatic flocking [14][15][16][17], and electrostatic copying [18,19], the accumulation discharge of charges and electrostatic attraction also pose significant hazards. For example, electrostatic discharge may cause electromagnetic interference and circuit breakdown in electronic devices [20,21], high-voltage electrostatic discharge poses a threat to personal safety [22], and electrostatic discharge in dusty environments may lead to explosions and fires [23][24][25]. ...
The phenomenon of surface charging, known as contact electrification or tribocharging, has wide-ranging applications but also notable hazards. Precisely measuring surface charge density in insulating materials is crucial for optimizing tribocharging and mitigating adverse effects. Although the vibrating capacitor method is commonly used for this purpose, its principle, designed for conductive materials, limits direct application to insulating surfaces, leaving the relationship between measured surface potential and surface charge density unclear. To address this issue, this study simulated the process of measuring the surface potential of insulating materials using Comsol simulations. It analyzed the effects of charged area size, probe height, and probe position, and utilized the spatial distribution of potential measurement values of surface point charges to derive an integral relationship between the distribution of measured surface potential values and the distribution of surface charge density. The integral relationship of surface potential distribution under different forms of surface charge density distributions calculated from this formula largely matches the numerical simulation results. Based on this, a relationship between the distribution of surface charge density and surface potential measurement values was further derived. This relationship can be used for measuring the surface charge density of insulating materials.
... By constructing a transparent conductive layer of aluminium-doped zinc oxide (AZO) on the surface of the PV glass to make it a transparent conductive electrode and placing a metal pole plate with an applied voltage of 10 kV parallel to the electrode, charged soiling particles were removed under the action of electrostatic force, as shown in Figure 18. The results showed that this method is effective in removing soiling in an environment where the relative humidity of air is greater than 30% [148]. Our group conducted a study on this soiling removal method, and the results showed that the soiling removal rate does not depend on the film square resistance and the best soiling removal efficiency was achieved when the relative humidity was approximately 70%. ...
Photovoltaic (PV) power generation has become a key area for investment worldwide. Solar PV panels are the core components of PV power generation systems, and the accumulation of soiling on their surfaces has numerous adverse effects on power generation. This paper provides an overview of the soiling accumulation on PV panels and the existing soiling removal methods. Firstly, the sources of soiling particles and the mechanism of soiling fall are analyzed, based on which the accumulation of soiling on the surface of the PV panels is described in detail, and then the effect of the surface soiling on the PV panels is investigated in the order of optics‐thermology‐electrical, with the necessary semiempirical formulas provided to assist in more in‐depth analyses. In addition, the principles, status quo, effects, costs, advantages, and disadvantages of existing soiling removal methods are specifically described, thus providing a reference for the selection of soiling removal methods in different regions. The paper also analyses the soiling accumulation and removal challenges of PV panels in different regions of China. The results of the study are important for the improvement of the effectiveness of soiling removal and the rational optimization of the soiling removal scheme.
... EDS application methods involve fabricating transparent interdigitated indium tin oxide microelectrode arrays that are embedded in a dielectric film, or installing insulated copper mesh electrodes on the surface of photovoltaic panels. Another electrostatic cleaning system has been developed, in which dust particles are repelled from the electrodes by charge induction assisted by adsorbed moisture [31]. This system makes it possible to define the electrical potential threshold required to remove particles during dust removal over a wide range of relative humidity. ...
... The statistics suggest that the lack of cleaning of photovoltaic modules can lead to an efficiency loss of 15-20%; a "mundane" problem like dust can actually reduce efficiency by up to 7% [21]. Associated with the cleaning of surfaces is the phenomenon known as "Hot Spot", which involves the overheating of shaded or, indeed, dirty cells (and is also due to module production defects). ...
... Currently, waterless cleaning methods to remove dust from solar installations are in the experimental phase, involving robots, drones, sensors and self-cleaning modules (equipped with electrodes embedded directly in the glass covering the module). The results of automating cleaning with robots claims 80% water savings compared to manual cleaning [21]. It is important to note that these methods have not been considered in this article in the environmental assessments. ...
... Regarding the cleaning interventions of the PV modules, the associated environmental impacts are related to the consumption of demineralized water per m 2 [33]. The ever-expanding photovoltaic sector consumes large quantities of water, which is why increasingly efficient solutions will need to be developed to sustainably reduce its water footprint [21]. ...
In the context of policies promoting renewable energies for decarbonization, energy transition and the development of energy communities, photovoltaic systems require special attention. Even for these systems, it is legitimate to inquire about the correlation, currently carried out through life cycle analysis, between benefits and environmental impacts. To maintain long-term productivity levels and ensure the proper functioning of the system, maintenance interventions are necessary. While these interventions guarantee performance, they also have repercussions for the environment. This study aims to assess the environmental impacts caused by ordinary and extraordinary maintenance interventions, taking into account specific factors, during the 30-year operational phase. To evaluate these impacts, this study verifies the feasibility of using data from Environmental Product Declaration (EPD) and the Product Category Rules (PCR) as reference. The initial results highlight, on the one hand, among the main issues, the importance that all EPDs attribute to the impacts caused by water consumption during the use phase of the PV modules, and on the other hand, some critical issues mainly due to the lack of data relating to the installation site necessary for the correct planning of maintenance activities. Finally, the study presents some reflections for a potential recalibration of the PCR and their associated EPDs.
... According to the above simulation results, the electronic driving system mentioned above is used to verify the characteristics of film dust removal and anti-fogging, respectively. Particles which originate from the air and the earth's surface are mainly composed of quartz (SiO 2 ), calcite (CaCO 3 ), and orthoclase (NaAlSi 3 O 8 ) [47,48]. In order to facilitate the construction of three parallel electrodes in a plane, the electrode shape is designed as a spiral structure. ...
The deposition of dust and condensation of fog will block the scattering and transmission of light, thus affecting the performance of optical devices. In this work, flexible polyethylene terephthalate (PET) foil functionalized by active dust removal and anti-fogging characteristics is realized which combines electrodynamic screen (EDS) and electro-heating devices. In lieu of traditional measurement methods of dust removal efficiency, the PSNR is employed to characterize the dust removal efficiency of the film for the first time. The results show that both dust removal and anti-fogging improve the image quality, in which the dust removal increases the PSNR from 28.1 dB to 34.2 dB and the anti-fogging function realizes a film temperature rise of 16.7 ∘C in 5 min, reaching a maximum of 41.3 ∘C. According to the high sensitivity of the PSNR, we propose a fully automatic CIS film-driven algorithm, and its feasibility has been demonstrated.
... Cleaning methods that are not environmentally friendly might result in electrical arcing and poor water conductivity. Dry cleaning, on the other hand, is less successful at eliminating dust and causes irreversible surface damage, which lowers light transmission over time (Panat and Varanasi, 2022). ...
... Earlier study reported that the power output of solar panels would decrease by more than 90% when the dust deposition mass per unit area reaches 20 mg/cm 2 [36] . Similarly, the radiative cooling surface could also be ineffective ( i.e. , with no cooling effect) when dust deposition mass is at a high level. ...
... Panat and Varanasi (2022), this process relies predominantly on the van der Waals method of ...
Arsenic (As) contamination poses a significant threat to human health, ecosystems, and agriculture, with levels ranging from 12 to 75% attributed to mine waste and stream sediments. This naturally element is abundant in Earth's crust and gets released into the environment through mining and rock processing, causing ≈363 million people to depend on As-contaminated groundwater. To combat this issue, introducing a sustainable hydrochar system has achieved a remarkable removal efficiency of over 92% for arsenic through adsorption. This comprehensive review presents an overview of As contamination in the environment, with a specific focus on its impact on drinking water and wastewater. It delves into the far-reaching effects of As on human health, ecosystems, aquatic systems, and agriculture, while also exploring the effectiveness of existing As treatment systems. Additionally, the study examines the potential of hydrochar as an efficient adsorbent for As removal from water/wastewater, along with other relevant adsorbents and biomass-based preparations of hydrochar. Notably, the fusion of hydrochar with nanoparticle-centric approaches presents a highly promising and environmentally friendly solution for achieving the removal of As from wastewater, exceeding >99% efficiency. This innovative approach holds immense potential for advancing the realms of green chemistry and environmental restoration. Various challenges associated with As contamination and treatment are highlighted, and proposed solutions are discussed. The review emphasizes the urgent need to advance treatment technologies, improve monitoring methods, and enhance regulatory frameworks. Looking outlook, the article underscores the importance of fostering research efforts, raising public awareness, and fostering interdisciplinary collaboration to address this critical environmental issue. Such efforts are vital for UN Sustainable Development Goals, especially clean water and sanitation (Goal 6) and climate action (Goal 13), crucial for global sustainability.
... A voltage of 12 KV was applied to achieve a 95% recovery of lost power from the test solar panel. Contrary to other EDS research, where relative humidity causes increased adhesion forces on the particle, this study leveraged the humidity condition to induce the charging of dust particle to clean the solar panels' surface [103]. developed an EDS prototype on a printed circuit board (PCB), in which the electrode width was 80 μm, and interelectrode spacing was between 400 and 800 μm. ...
Dust accumulation on the surface of solar harvesting devices can significantly reduce energy yield. Electrody-namic Shield (EDS) technology can remove dust via an electric field generated on the top layer of the solar harvesting devices. This technology does not require the use of water and can operate with a fraction of the power generated by the solar harvesting devices. The electric field is generated by applying a voltage across electrodes deposited on the surface of the solar harvesting devices. Extensive research is being carried out to: (1) Identify and characterize important parameters and their effect on the cleaning efficiency of the EDS, (2) improve the optical transmission and conductive properties of the electrodes, and (3) develop scalable electrode coatings. This review paper discusses the current state of research on EDS technology, mechanisms of dust removal, parameters that determine cleaning efficiency, and recent advances in the application of EDS for both space and terrestrial applications. The literature on the impact of electrode geometry is less than adequately needed to understand its effects on cleaning efficiency. The independent role of frequency and waveshape applied to an EDS remains an open research question. The main challenges that need to be addressed before this technology can be successfully implemented on a large scale include: (1) increasing the efficiency of fine dust particle removal while optimizing for power consumption, (2) further experimental validation of theoretical models built to calculate cleaning efficiency for simulated EDS, and (3) exploring new materials to manufacture electrodes at scale.
... The aim was to select values that align with similar studies conducted in the field. This approach ensures that the findings can be effectively compared and contextualized within the broader body of research on similar topics [57][58][59]. After each experiment, the surface of the panel was thoroughly cleaned with a brush before starting the next experiment. ...
... When the voltage is positive, the wind is caused by the transfer of momentum from positive ions to neutral particles. However, when the voltage is negative, the main source of the wind is the transfer of momentum from electrons and negative ions to neutral particles, with positive ions contributing only in a small area near the electrode corona [57]. The velocity of the electric wind depends thus on the polarity of the corona discharge, which is determined by the types of particles involved in its generation. ...
