Transparent Electrodynamic Screen (EDS) Films - Industrial Production and Lamination onto PV Modules and CSP Mirrors for Self Cleaning Function

AbstractElectrodynamic screens (EDS) are transparent dielectric films, consisting of embedded, interdigitated parallel conducting electrodes that can be integrated onto the optical surface of a photovoltaic (PV) module or concentrated solar power (CSP) mirror for their self-cleaning function to mitigate the energy yield losses caused by soiling. The EDS film removes dust particles using electrostatic forces thus eliminating the need for water or robotic devices to clean the solar devices. In this paper we report the methods experimented to produce EDS film stacks integrated onto individual PV modules (33 cm x 28 cm) for solar field applications using an industrial vacuum lamination process for the purpose of outdoor testing. Steps taken to optimize the lamination process to provide high optical transparency, resistance against moisture ingress and to withstand dust abrasion are described. The experiments performed to arrive at the optimal curing temperature, curing time, and vacuum pressure maintenance for the lamination process are elaborated. Details on the construction, functionality and operation of the outdoor testing units are provided. Measurements of the optical transmission efficiency (TE) and output power restoration (OPR) of the EDS film stack laminated onto PV modules are presented along with a model for full-scale lamination with an aim for advancing the EDS film technology as a commercially available product.

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Development of Transparent Electrodynamic Screens on Ultrathin Flexible Glass Film Substrates for Retrofitting Solar Panels and Mirrors for Self-Cleaning Function

MRS Advances ◽

10.1557/adv.2016.60 ◽

2016 ◽

Vol 1 (15) ◽

pp. 1003-1012 ◽

Cited By ~ 4

Author(s):

M. K. Mazumder ◽

J. W. Stark ◽

C. Heiling ◽

M. Liu ◽

A. Bernard ◽

...

Keyword(s):

Large Scale ◽

Transmission Efficiency ◽

Silver Nanowire ◽

Dust Particles ◽

Glass Film ◽

Solar Collectors ◽

Solar Panels ◽

Labor Costs ◽

Adhesive Film ◽

Self Cleaning

ABSTRACTDevelopment of transparent electrodynamic screens (EDS) printed on ultrathin flexible glass film substrates for retrofitting on solar panels and solar mirrors to perform self cleaning function is reviewed. Large-scale solar plants are generally installed in semi-arid and desert areas where dust layers build up on solar collectors causes major energy-yield loss. Maintaining designed plant capacities requires more than 90% reflectivity for CSP mirrors and 90% transmission efficiency for PV modules; solar collectors must therefore be cleaned at a frequency depending on the rate of dust deposition. Scarcity of water in these regions requires a cleaning method that drastically reduces or eliminates water and the associated labor costs for high efficiency operation of large-scale solar plants. An EDS film consists of rows of interdigitated, transparent conducting parallel electrodes embedded within a flexible ultrathin glass film and an optically clear adhesive film used for retrofitting the film on the surface of solar collectors. When phased voltage pulses activate the electrodes, the dust particles are first electrostatically charged, then repelled and removed from the surface of the solar collectors by Coulomb force, restoring transmission efficiency greater than 90%. The electrodes of EDS are either made from silver nanowire or another conductive transparent material printed on a highly transparent, ultrathin (100-μm thick), flexible borosilicate glass film. Applications of different conducting transparent electrodes and methods of printing are reviewed for optimizing self-cleaning function of solar panels and mirrors.

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Performance Enhancement of Self-Cleaning Hydrophobic Nanocoated Photovoltaic Panels in a Dusty Environment

Energies ◽

10.3390/en14206800 ◽

2021 ◽

Vol 14 (20) ◽

pp. 6800

Author(s):

Emran Aljdaeh ◽

Innocent Kamwa ◽

Waleed Hammad ◽

Mohammed I. Abuashour ◽

Tha’er Sweidan ◽

...

Keyword(s):

Performance Enhancement ◽

Hydrophobic Surface ◽

Experimental Tests ◽

Sio2 Nanoparticles ◽

Dust Particles ◽

Substantial Impact ◽

Pv Panel ◽

Pv Module ◽

Pv Modules ◽

Self Cleaning

The efficiency of a photovoltaic (PV) panels drops significantly in dusty environments. The variation in temperature could have a substantial impact on PV panel cells, which could further lead to high deterioration and eventually permanent damage to the PV material in the presence of dust. To resolve this issue, in this work a novel hydrophobic silicon dioxide (SiO2)-based nanoparticle coating is proposed for the PV panel, to shrink the surface stress developed between the water and the coated facet. Two identical PV modules were installed to conduct comparable experimental tests simultaneously. The first module is coated by the SiO2 nanoparticles, and the second is uncoated and used as a reference. To maintain coherency, the experiments are done in the same environmental conditions, cleaning the PV modules at regular intervals. Results reveal that the accumulated energy generated during this period of study was comprehensively enhanced. Moreover, the self-cleaning property of the hydrophobic surface of the coated panel allowed water droplets to slide smoothly down the PV module surface, carrying dust particles. Useful recommendations are made at the end to enhance the performance of PV panels in dusty environments.

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A Simple Mismatch Mitigating Partial Power Processing Converter for Solar PV Modules

Energies ◽

10.3390/en14082308 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2308

Author(s):

Kamran Ali Khan Niazi ◽

Yongheng Yang ◽

Tamas Kerekes ◽

Dezso Sera

Keyword(s):

Experimental Tests ◽

Energy Yield ◽

Power Electronic ◽

Solar Pv ◽

Partial Shading ◽

Loss Analysis ◽

Pv Systems ◽

Pv Module ◽

Pv Modules ◽

In Series

Partial shading affects the energy harvested from photovoltaic (PV) modules, leading to a mismatch in PV systems and causing energy losses. For this purpose, differential power processing (DPP) converters are the emerging power electronic-based topologies used to address the mismatch issues. Normally, PV modules are connected in series and DPP converters are used to extract the power from these PV modules by only processing the fraction of power called mismatched power. In this work, a switched-capacitor-inductor (SCL)-based DPP converter is presented, which mitigates the non-ideal conditions in solar PV systems. A proposed SCL-based DPP technique utilizes a simple control strategy to extract the maximum power from the partially shaded PV modules by only processing a fraction of the power. Furthermore, an operational principle and loss analysis for the proposed converter is presented. The proposed topology is examined and compared with the traditional bypass diode technique through simulations and experimental tests. The efficiency of the proposed DPP is validated by the experiment and simulation. The results demonstrate the performance in terms of higher energy yield without bypassing the low-producing PV module by using a simple control. The results indicate that achieved efficiency is higher than 98% under severe mismatch (higher than 50%).

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Optimal Design of a Six-Bar Linkage for an Anthropomorphic Three-Jointed Finger Mechanism

22nd Biennial Mechanisms Conference: Robotics, Spatial Mechanisms, and Mechanical Systems ◽

10.1115/detc1992-0227 ◽

1992 ◽

Author(s):

Jichuan Zhang ◽

Gongliang Guo ◽

William A. Gruver

Keyword(s):

Mathematical Model ◽

Nonlinear Programming ◽

Optimal Design ◽

Transmission Efficiency ◽

Degree Of Freedom ◽

Optimal Parameters ◽

Joint Friction ◽

Robotic Devices ◽

End Effectors ◽

Human Finger

Abstract We treat the design of a three-jointed, anthropomorphic, finger mechanism for prostheses and robotic end-effectors. Based on the study of configurations for the human finger, we propose a six-bar linkage with one degree of freedom for the finger mechanism. A model of the fingertip displacement of the mechanism is derived by a vector analysis approach. We study the effects of joint friction on the transmission efficiency. By measuring the joint positions of a human finger, we develop a mathematical model of the pinching and holding configurations for the human finger. Optimal parameters for the finger mechanism are obtained by nonlinear programming based on motion posture, locus, transmission efficiency, and weight subject to geometric and bionic constraints. Simulations indicate that the mechanism is useful in a variety of prosthetic and robotic devices.

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Outdoor Performance Test of Bifacial n-Type Silicon Photovoltaic Modules

Sustainability ◽

10.3390/su11226234 ◽

2019 ◽

Vol 11 (22) ◽

pp. 6234 ◽

Cited By ~ 1

Author(s):

Hyeonwook Park ◽

Sungho Chang ◽

Sanghwan Park ◽

Woo Kyoung Kim

Keyword(s):

Tilt Angle ◽

Performance Test ◽

Power Production ◽

Energy Yield ◽

Concrete Floor ◽

Photovoltaic Modules ◽

Pv Module ◽

Pv Modules ◽

Solar Tracker ◽

One Year

The outdoor performance of n-type bifacial Si photovoltaic (PV) modules and string systems was evaluated for two different albedo (ground reflection) conditions, i.e., 21% and 79%. Both monofacial and bifacial silicon PV modules were prepared using n-type bifacial Si passivated emitter rear totally diffused cells with multi-wire busbar incorporated with a white and transparent back-sheet, respectively. In the first set of tests, the power production of the bifacial PV string system was compared with the monofacial PV string system installed on a grey concrete floor with an albedo of ~21% for approximately one year (June 2016–May 2017). In the second test, the gain of the bifacial PV string system installed on the white membrane floor with an albedo of ~79% was evaluated for approximately ten months (November 2016–August 2017). During the second test, the power production by an equivalent monofacial module installed on a horizontal solar tracker was also monitored. The gain was estimated by comparing the energy yield of the bifacial PV module with that of the monofacial module. For the 1.5 kW PV string systems with a 30° tilt angle to the south and 21% ground albedo, the year-wide average bifacial gain was determined to be 10.5%. An increase of the ground albedo to 79% improved the bifacial gain to 33.3%. During the same period, the horizontal single-axis tracker yielded an energy gain of 15.8%.

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Use of Steel Industry Wastes for the Preparation of Self-Cleaning Mortars

Materials ◽

10.3390/ma12040621 ◽

2019 ◽

Vol 12 (4) ◽

pp. 621 ◽

Cited By ~ 3

Author(s):

José Balbuena ◽

Luis Sánchez ◽

Manuel Cruz-Yusta

Keyword(s):

Steel Industry ◽

Diffuse Reflectance ◽

Construction Material ◽

Added Value ◽

X Ray Diffraction ◽

X Ray ◽

Before And After ◽

New Material ◽

Lamination Process ◽

Self Cleaning

An important problem, which must be solved, is the accumulation of industrial waste in landfills. Science has an obligation to transform this waste into new products and, if possible, with high added value. In this sense, we propose the valorization of the waste which is generated in the steel lamination process (HSL) through its conversion into a new material with photocatalytic activity which is suitable for use as an additive to obtain a self-cleaning construction material. The valorization of steel husk lamination waste is achieved through a grinding process, which allows the sample to be homogenized, in size, without altering its phase composition, and a thermal treatment that turns it into iron oxide, which acts as a photocatalyst. These residues, before and after treatment, were characterized by different techniques such as PXRD (Powder X-Ray Diffraction), TGA (Thermogravimetric Analysis), SBET (Specific surface area, Brunauer-Emmett-Teller), SEM (Scanning Electron Microscopy) and Diffuse reflectance (DR). MB and RhB tests show that this material is capable of self-cleaning, both of the material itself and when it is incorporated into a construction material (mortar). In addition, the NOx gas elimination test shows that it is also capable of acting on greenhouse gases such as NOx.

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Measurement and Modeling of 3D Solar Irradiance for Vehicle-Integrated Photovoltaic

Applied Sciences ◽

10.3390/app10030872 ◽

2020 ◽

Vol 10 (3) ◽

pp. 872 ◽

Cited By ~ 2

Author(s):

Kenji Araki ◽

Yasuyuki Ota ◽

Masafumi Yamaguchi

Keyword(s):

Solar Irradiance ◽

Random Distribution ◽

Curved Surface ◽

Energy Yield ◽

Car Body ◽

Pv Modules ◽

The Difference ◽

One Year

The energy yield of vehicle-integrated photovoltaics (VIPV) differs from that of standard photovoltaics (PV). It is mainly by the difference of the solar irradiance onto the car roof and car bodies as well as its curved shape. Both meaningful and practical modeling and measurement of solar irradiance for VIPV need to be established, rather than the extension of the current technologies. The solar irradiance is modeled by a random distribution of shading objects and car orientation with the correction of the curved surface of the PV modules. The measurement of the solar irradiance onto the car roof and car body is done using five pyranometers in five local axes on the car for one year. The measured dynamic solar irradiance onto the car body and car roof is used for validation of the solar irradiance model in the car.

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Optical Modeling of Reflectivity Loss Caused by Dust Deposition on CSP Mirrors and Restoration of Energy Yield by Electrodynamic Dust Removal

Volume 1: Combined Energy Cycles, CHP, CCHP, and Smart Grids; Concentrating Solar Power, Solar Thermochemistry and Thermal Energy Storage; Geothermal, Ocean, and Emerging Energy Technologies; Hydrogen Energy Technologies; Low/Zero Emission Power Plants and Carbon Sequestration; Photovoltaics; Wind Energy Systems and Technologies ◽

10.1115/es2014-6506 ◽

2014 ◽

Cited By ~ 2

Author(s):

Jeremy Stark ◽

Julius Yellowhair ◽

John N. Hudelson ◽

Mark Horenstein ◽

Malay Mazumder

Keyword(s):

Power Plants ◽

Specular Reflection ◽

Mie Scattering ◽

Dust Removal ◽

Dust Particles ◽

Energy Yield ◽

Dust Deposition ◽

Optical Modeling ◽

Specular Reflectivity ◽

Semi Arid

For large scale CSP power plants, vast areas of land are needed in deserts and semi-arid climates where uninterrupted solar irradiance is most abundant. These power facilities use large arrays of mirrors to reflect and concentrate sunlight onto collectors, however, dust deposition on the optical surfaces causes obscuration of sunlight, resulting in large energy-yield losses in solar plants. This problem is compounded by the lack of natural clean water resources for conventional cleaning of solar mirrors, often with reflective surface areas of large installations exceeding a million square meters. To investigate the application of transparent electrodynamic screens (EDS) for efficient and cost effective dust removal from solar mirrors, both optical modeling and experimental verifications were performed. Prototype EDS-integrated mirrors were constructed by depositing a set of parallel transparent electrodes into the sun-facing surface of solar mirrors and coating electrodes with thin transparent dielectric film. Activation of the electrodes with a three-phase voltage creates an electrodynamic field that charges and repels dust electrostatically by Coulomb force and sweeps away particles by a traveling electrodynamic wave. We report here brief discussions on (1) rate of deposition and the properties of dust with respect to their size distribution and chemical composition in semi-arid areas of the southwest US and Mojave Desert and their adhesion to solar mirrors, (2) optical models of: (a) specular reflection losses caused by scattering and absorption by dust particles deposited on the surface based on Mie scattering theory, and (b) reflection loss by the integration of EDS on the mirror surface, computed by FRED ray-tracing model. The objective is to maintain specular reflectivity of 90% or higher by frequent removal of dust by EDS. Our studies show that the incorporation of transparent EDS would cause an initial loss of 3% but would be able to maintain specular reflectivity more than 90% to meet the industrial requirement for CSP plants. Specular reflection measurements taken inside a climate controlled environmental chamber show that EDS integration can restore specular reflectivity and would be able to prevent major degradation of the optical surface caused by the deposition of dust.

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