Furthur Analysis of Accelerated Exposure Testing of Thin-Glass Mirror Matrix

2007 ◽  
Author(s):  
C. E. Kennedy ◽  
K. Terwilliger ◽  
G. J. Jorgensen
Keyword(s):  
Lead Free ◽  
Advanced Materials ◽  
Thin Glass ◽  
Metal Substrates ◽  
Solar Systems ◽  
Free Process ◽  
Hemispherical Reflectance ◽  
Designed Experiment ◽  
Exposure Testing ◽  
The Cost

Concentrating solar power (CSP) companies have deployed thin-glass mirrors produced by wet-silver processes on ∼1-mm-thick, relatively lightweight glass. These mirrors are bonded to metal substrates in commercial installations and have the confidence of the CSP industry. Initial hemispherical reflectance is ∼93%–96%, and the cost is ∼$16.1/m2–$43.0/m2. However, corrosion was observed in mirror elements of operational solar systems deployed outdoors for 2 years. National Renewable Energy Laboratory (NREL) Advanced Materials Team has been investigating this problem. First, it was noted that this corrosion is very similar to the corrosion bands and spots observed on small (45 mm × 67 mm) thin-glass mirrors laminated to metal substrates with several different types of adhesives and subjected to accelerated exposure testing (AET) at NREL. The corrosion appears as dark splotches in the center of the mirror, with a corresponding 5%–20% loss in reflectivity. Secondly, two significant changes in mirror manufacture have occurred in the wet-chemistry process because of environmental concerns. The first is the method of forming a copper-free reflective mirror, and the second is the use of lead-free paints. However, the copper-free process requires stringent quality control and the lead-free paints were developed for interior applications. A test matrix of 84 combinations of sample constructions (mirror type/back-protective paint/adhesive/substrate) was devised for AET as a designed experiment to identify the most-promising mirrors, paints, and adhesives for use with concentrator designs. Two types of accelerated exposure were used: an Atlas Ci5000 WeatherOmeter (CI5000) and a BlueM damp-heat chamber. Based on an analysis of variance (ANOVA), the various factors and interactions were modeled. These samples now have more than 36 months of accelerated exposure, and most samples have completed their test cycle. We will discuss the results of the final exposure testing of these mirror samples. Glass mirrors with copper back-layers and heavily leaded paints have been considered robust for outdoor use. However, the basic mirror composition of the new mirrors is radically different from that of historically durable solar mirrors, and the outdoor durability must be determined.

Analysis of Accelerated Exposure Testing of Thin-Glass Mirror Matrix

Solar Energy ◽  
2005 ◽  
Author(s):  
C. E. Kennedy ◽  
K. Terwilliger ◽  
G. J. Jorgensen
Keyword(s):  
Lead Free ◽  
Thin Glass ◽  
Metal Substrates ◽  
Solar Systems ◽  
Paint Systems ◽  
Heat Chamber ◽  
Hemispherical Reflectance ◽  
Designed Experiment ◽  
Exposure Testing ◽  
The Cost

Concentrating solar power (CSP) companies have deployed thin-glass mirrors produced by wet silver processes on ∼1-mm-thick, relatively lightweight glass. These mirrors have been bonded to metal substrates in commercial installations. Initial hemispherical reflectance is ∼93% to 96%, and the cost is ∼$16.1/m2 to $43.0/m2. These mirrors have the confidence of the CSP industry. However, corrosion was observed in mirror elements of operational solar systems deployed outdoors for 2 years. NREL’s advanced optical materials team was assigned to investigate the problem. First, it was noted that this corrosion is very similar to the corrosion bands and spots observed on small (45 mm × 67 mm) thin-glass mirrors laminated to metal substrates with several different types of adhesives and subjected to accelerated exposure testing (AET) at NREL. These samples exhibited corrosion at the unprotected edges and along cracks, and the choice of adhesive affected the performance of weathered thin-glass mirrors. Secondly, two significant changes in mirror manufacture have occurred in the wet-chemistry process because of environmental concerns. The first is the method of forming a copper-free reflective mirror, and the second is the use of lead-free paints. A test matrix of 84 combinations of sample constructions (mirror type / back protective paint / adhesive / substrate) was devised for AET as a designed experiment to identify the most promising mirrors, paints, and adhesives for use with concentrator designs. Two types of accelerated exposure were used: an Atlas Ci5000 WeatherOmeter (WOM) and a damp-heat chamber. Based on an analysis of variance (ANOVA), the various factors and interactions were modeled. These samples now have almost 24 months of accelerated exposure. Analysis of the thin-glass mirror matrix indicated that the Glaverbel mirror with a copperless formulation demonstrates slightly better performance compared to the Naugatuck standard copper-containing mirror and new copperless constructions although most results are within experimental uncertainty. Analysis of the thin-glass mirror matrix indicates commercial (non-mirror) back-protective paint applied after mirror manufacturing is not beneficial. Degradation of the samples exposed to date in the damp-heat chamber is similar, but at a rate 10 times faster than observed for samples in the WOM. We will discuss the results of the continued exposure testing of these mirror samples. Although glass mirrors with copper back-layers and heavily leaded paints have been considered robust for outdoor use, the new copperless back-layer and lead-free paint systems were designed for interior mirror applications and the outdoor durability must be determined.

Optical Durability of Candidate Solar Reflectors

2005 ◽  
Vol 127 (2) ◽  
pp. 262-269 ◽  
Author(s):  
C. E. Kennedy ◽  
K. Terwilliger
Keyword(s):  
Cone Angle ◽  
Front Surface ◽  
Advanced Materials ◽  
Accelerated Weathering ◽  
Thin Glass ◽  
Specular Reflectance ◽  
Outdoor Environments ◽  
Exposure Testing ◽  
Durability Testing ◽  
Main Activity

Concentrating solar power (CSP) technologies use large mirrors to collect sunlight to convert thermal energy to electricity. The viability of CSP systems requires the development of advanced reflector materials that are low in cost and maintain high specular reflectance for extended lifetimes under severe outdoor environments. The long-standing goals for a solar reflector are specular reflectance above 90% into a 4 mrad half-cone angle for at least 10 years outdoors with a cost of less than $13.8/m2 (the 1992 $10.8/m2 goal corrected for inflation to 2002 dollars) when manufactured in large volumes. Durability testing of a variety of candidate solar reflector materials at outdoor test sites and in laboratory accelerated weathering chambers is the main activity within the Advanced Materials task of the CSP Program at the National Renewable Energy Laboratory (NREL) in Golden, Colorado. Test results to date for several candidate solar reflector materials will be presented. These include the optical durability of thin glass, thick glass, aluminized reflectors, front-surface mirrors, and silvered polymer mirrors. The development, performance, and durability of these materials will be discussed. Based on accelerated exposure testing the glass, silvered polymer, and front-surface mirrors may meet the 10 year lifetime goals, but at this time because of significant process changes none of the commercially available solar reflectors and advanced solar reflectors have demonstrated the 10 year or more aggressive 20 year lifetime goal.

scholarly journals COST531 project: Study of the advanced materials for lead free soldering

2007 ◽  
Vol 43 (2) ◽  
pp. 113-123 ◽  
Author(s):  
A. Kroupa ◽  
A.T. Dinsdale ◽  
A. Watson ◽  
J. Vrestal ◽  
A. Zemanova
Keyword(s):  
Scientific Information ◽  
Lead Free ◽  
Advanced Materials ◽  
Basic Knowledge ◽  
Lead Free Solder ◽  
Project Study ◽  
Free Solder ◽  
Basic Features ◽  
The Cost ◽  
Model Phase

The COST 531 [1] project runt in the years 2002-2007, and dealt with the materials suitable for lead-free soldering. The main aim was to increase the basic knowledge on possible alloy systems that were used or planned to be used as lead-free solder materials and offer scientific information about these materials in order to replace the currently used lead-containing solders. The databases of materials and thermodynamic properties are one of the expected results and the basic features and properties of the thermodynamic database, allowing to model phase diagrams in multicomponent systems, are described in following paper.

Optical Durability of Candidate Solar Reflectors

Solar Energy ◽  
2004 ◽  
Author(s):  
C. E. Kennedy ◽  
K. Terwilliger
Keyword(s):  
Cone Angle ◽  
Front Surface ◽  
Advanced Materials ◽  
Accelerated Weathering ◽  
Thin Glass ◽  
Specular Reflectance ◽  
Outdoor Environments ◽  
Exposure Testing ◽  
Durability Testing ◽  
Main Activity

Concentrating solar power (CSP) technologies use large mirrors to collect sunlight to convert thermal energy to electricity. The viability of CSP systems requires the development of advanced reflector materials that are low in cost and maintain high specular reflectance for extended lifetimes under severe outdoor environments. The long-standing goals for a solar reflector are specular reflectance above 90% into a 4-mrad half-cone angle for at least 10 years outdoors with a cost of less than $13.8/m2 (the 1992 $10.8/m2 goal corrected for inflation to 2002 dollars) when manufactured in large volumes. Durability testing of a variety of candidate solar reflector materials at outdoor test sites and in laboratory accelerated weathering chambers is the main activity within the Advanced Materials task of the CSP Program at the National Renewable Energy Laboratory (NREL) in Golden, Colorado. Test results to date for several candidate solar reflector materials will be presented. These include the optical durability of thin glass, thick glass, aluminized reflectors, frontsurface mirrors, and silvered polymer mirrors. The development, performance, and durability of these materials will be discussed. Based on accelerated exposure testing the glass, silvered polymer, and front-surface mirrors may meet the 10-year lifetime goals, but at this time because of significant process changes none of the commercially available solar reflectors and advanced solar reflectors have demonstrated the 10-year or more aggressive 20-year lifetime goal.

scholarly journals Exergy Assessment and Thermo-Economic Analysis of Hybrid Solar Systems with Seasonal Storage and Heat Pump Coupling in the Social Housing Sector in Zaragoza

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1279
Author(s):  
Amaya Martínez-Gracia ◽  
Sergio Usón ◽  
Mª Teresa Pintanel ◽  
Javier Uche ◽  
Ángel A. Bayod-Rújula ◽  
...  
Keyword(s):  
Heat Pump ◽  
Social Housing ◽  
Energy System ◽  
Simulation Software ◽  
Solar Panels ◽  
Solar Systems ◽  
Under Construction ◽  
The Cost ◽  
Solar Resource ◽  
Solar Field

A real case study of an energy system based on a Solar Assisted Heat Pump (SAHP) fed by hybrid photovoltaic-thermal solar panels (PVT) and seasonal storage (SS) is presented in this paper. Exergy and exergy cost analyses are proposed as complementary methods for the assessment and better understanding of the efficiency of this cogeneration solar configuration. The system performance takes advantage of storage heat in summer, when the solar resource is high in Spain, and is then later consumed during the cold winter (heating season). The building is devoted to social housing, and it is currently under construction. The assessment is based on simulations developed using TRNSYS, a dynamic simulation software for energy systems. Results show that the unit exergy cost of the solar field is around 6. The cost of the seasonal storage is higher, about 13, and its formation is affected both by its own irreversibility and by the irreversibility of the PVT solar field. The cost of the heat delivered by the heat pump is around 15, being affected by all the upstream units and even by the grid. Besides, the analysis points out strategies for improving the system efficiency, such as increasing the size of the storage tank or improving the control strategy of the boiler.

scholarly journals Progress of MOF-Derived Functional Materials Toward Industrialization in Solar Cells and Metal-Air Batteries

Catalysts ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 897
Author(s):  
Mohamed Elhousseini Hilal ◽  
Abdelkhalk Aboulouard ◽  
Abdul Rehman Akbar ◽  
Hussein A. Younus ◽  
Nesrin Horzum ◽  
...  
Keyword(s):  
Photovoltaic Cells ◽  
Functional Materials ◽  
High Reactivity ◽  
Life Cycles ◽  
Advanced Materials ◽  
Conversion Materials ◽  
Metal Organic ◽  
Power Outputs ◽  
Electrical Demand ◽  
The Cost

The cutting-edge photovoltaic cells are an indispensable part of the ongoing progress of earth-friendly plans for daily life energy consumption. However, the continuous electrical demand that extends to the nighttime requires a prior deployment of efficient real-time storage systems. In this regard, metal-air batteries have presented themselves as the most suitable candidates for solar energy storage, combining extra lightweight with higher power outputs and promises of longer life cycles. Scientific research over non-precious functional catalysts has always been the milestone and still contributing significantly to exploring new advanced materials and moderating the cost of both complementary technologies. Metal-organic frameworks (MOFs)-derived functional materials have found their way to the application as storage and conversion materials, owing to their structural variety, porous advantages, as well as the tunability and high reactivity. In this review, we provide a detailed overview of the latest progress of MOF-based materials operating in metal-air batteries and photovoltaic cells.

scholarly journals By The Numbers: Grid Energy Storage gets Cheaper

2018 ◽  
Vol 140 (04) ◽  
pp. 28-29
Author(s):  
Jeffrey Winters
Keyword(s):  
New York ◽  
Energy Storage ◽  
Lithium Ion ◽  
Solar Systems ◽  
Ion Storage ◽  
Investment Firm ◽  
Storage Technologies ◽  
The Cost ◽  
Grid Storage ◽  
Modern Technologies

This article discusses introduction of modern technologies to enhance electric grid storage. The New York investment firm Lazard released an analysis of energy storage technologies, based on the levelized cost. The analysis looked at two different common battery chemistries—lithium-ion and lead-acid—as well as flow batteries. Lazard analyzed the cost of ‘behind the meter’ applications, such as battery backups for residential solar systems or businesses trying to save demand at peak times. Lazard expects lithium-ion storage prices to continue dropping over the next 5 years. It is expected that the cost of storage may soon become cheap enough to make the spotty service of wind and solar power an annoyance, not a deal-breaker.

Pb-Free Process Development for a High End Storage Area Network Application

2007 ◽  
Author(s):  
Sunil Gopakumar ◽  
Francois Billaut ◽  
Eric Fremd ◽  
Manthos Economou
Keyword(s):  
Thermal Cycling ◽  
Cycling Performance ◽  
Lead Free ◽  
Process Window ◽  
Successful Implementation ◽  
Soldering Process ◽  
Wave Soldering ◽  
Free Process ◽  
Plated Through Hole ◽  
The Impact

Lead free solders are being increasingly used in the electronic industry. While most of the electronic products, in terms of volume, are already built lead free, sectors of the industry including high end servers, networking and telecommunications are covered by “lead in solder” exemptions. It is unknown at this point how long these exemptions will last. In addition, many components such as memories have started appearing only in the Pb-free version. As a result, the industry has been pushed to either adopt a mixed assembly process or to transition early to a full Pb-free process. Even though numerous papers have outlined the successful implementation of a Pb-free process, few of them have actually looked at complex high-end multilayer boards in its entirety. This paper focuses on the issues involved in developing an acceptable Pb-free process window for thick, multilayer boards for SMT, Wave soldering, Rework and Press-fit operations. A laminate capable of withstanding Pb-free soldering temperatures was used to construct a 125-mil thick multilayer board with 18 layers which included 8 ground and 10 signal planes. This experiment utilized two popular Pb-free finishes commonly used in the industry: Immersion Silver and high temperature Organic Solderability Preservative (OSP). The widespread SAC 305 alloy with a composition of Sn3.0Ag0.5Cu was used for both SMT and wave soldering. Three sets of assemblies were built: Pb-free, Mixed and Sn/Pb. The mixed assembly mostly used Pb-free components with Sn/Pb solder paste. The impact of increased soldering temperatures on the board, components and reliability of the product were also studied as a part of this research endeavor. Board level reliability tests were conducted by subjecting the boards from 0°C to 100°C Air-to-Air thermal cycling as well as mechanical shock and vibration tests. A suite of reliability and destructive physical analysis (DPA) tests were carried out to establish the quality of the soldering using the eutectic Sn/Pb assembly as the baseline. The study compared the cycling performance of the three sets of assemblies and also looked at the potential impacts of moving to mixed assemblies. Results indicated a reduced process window for Pb-free, especially for the Pb-free wave soldering process due to reduced wetting of the plated through hole barrels as compared to Sn/Pb wave soldering process. The thermal cycling performance of the three sets of assemblies was found to be equivalent after 6000 cycles.

An Investigation of the Lead-Free Surface Mount Soldering Process: Solder Joint Evaluation and Process Optimisation

2004 ◽  
Author(s):  
Claire Ryan ◽  
Jeff M. Punch ◽  
Bryan Rodgers ◽  
Greg Heaslip ◽  
Shane O’Neill ◽  
...  
Keyword(s):  
Screen Printing ◽  
Solder Joints ◽  
Lead Free ◽  
Lead Free Solder ◽  
Solder Paste ◽  
Surface Mount ◽  
Snagcu Solder ◽  
Soldering Process ◽  
Free Process ◽  
Free Solder

A European Union ban on lead in most electrical and electronic equipment will be imposed as of July 1st 2006. The ban, along with market pressures, means that manufacturers must transfer from a tin-lead soldering process to a lead-free process. In this paper the implications on the surface mount (SMT) soldering process are presented. A set of experiments was conducted to investigate the screen-printing and reflow steps of the SMT process using a tin-silver-copper (95.5Sn3.8Ag0.7Cu) solder and a baseline of standard tin-lead (63Sn37Pb). 10×10 arrays of micro Ball Grid Array (micro-BGA) components mounted on 8-layer FR4 printed wiring boards (PWBs) were used. The screen-printing experiment addressed the deposition of the solder paste on the board. The parameters used in the investigation were print speed, squeegee pressure, snap-off distance, separation speed and cleaning interval, with the responses being measurements of paste height and volume. Optimum screen-printer settings were determined which give adequate paste volume and height and a good print definition. The reflow experiment investigated the following parameters of the temperature profile: preheat, soak, peak and cool down temperatures, and conveyor speed. The resulting solder joints were evaluated using cross-section analysis and x-ray techniques in order to determine the presence of defects. A mechanical fatigue test was also carried out in order to compare the strength of the solder joints. The overall quality of the lead-free solder joints was determined from these tests and compared to that of tin-lead. The outcome is a set of manufacturing guidelines for transferring to lead-free solder including optimum screen-printer and reflow oven settings for use with an SnAgCu solder.

scholarly journals Recent Progress in Fabrication of Antimony/Bismuth Chalcohalides for Lead-Free Solar Cell Applications

Nanomaterials ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2284
Author(s):  
Yong Chan Choi ◽  
Kang-Won Jung
Keyword(s):  
Solar Cells ◽  
Recent Progress ◽  
Perovskite Solar Cells ◽  
Industrial Applications ◽  
Lead Free ◽  
Fabrication Method ◽  
Pb Toxicity ◽  
Interfacial Layers ◽  
Solar Systems ◽  
Comparable Performance

Despite their comparable performance to commercial solar systems, lead-based perovskite (Pb-perovskite) solar cells exhibit limitations including Pb toxicity and instability for industrial applications. To address these issues, two types of Pb-free materials have been proposed as alternatives to Pb-perovskite: perovskite-based and non-perovskite-based materials. In this review, we summarize the recent progress on solar cells based on antimony/bismuth (Sb/Bi) chalcohalides, representing Sb/Bi non-perovskite semiconductors containing chalcogenides and halides. Two types of ternary and quaternary chalcohalides are described, with their classification predicated on the fabrication method. We also highlight their utility as interfacial layers for improving other solar cells. This review provides clues for improving the performances of devices and design of multifunctional solar systems.

Sign in / Sign up

Export Citation Format

Share Document