Search NASA⌕ Search

SEARCH · Search NASA

Results for “Module manufacturing,”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 415 records · Page 23

Heterobarrier Varactors with Nonuniformly Doped Modulation Layers

Optimum shape of the capacitance–voltage (C–V) characteristic is a critical parameter determining the efficiency of frequency multiplication in heterobarrier varactors (HBVs) operating in the millimeter and submillimeter frequency ranges. A numerical model for calculating the C–V characteristics and leakage currents of HBV heterostructures with arbitrary composition and doping profiles has been verified on the basis of published and original experimental data. A specially designed HBV heterostructure with three undoped InAlAs/AlAs/InAlAs barriers surrounded by nonuniformly doped n-InGaAs modulation layers has been grown by molecular beam epitaxy on InP substrate. Prototype HBVs manufactured using the proposed heterostructure demonstrated a nearly cosine shape of the C–V curve at bias voltages up to 2 V, increased overlap capacitance, and low leakage currents.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Identification of Dynamic Force Coefficients for an Additively Manufactured Hermetic Squeeze Film Bearing Support Damper Utilizing a Pass-Through Channel

Abstract The following paper presents breakthrough experimental results for a new hermetic squeeze film damper (HSFD) concept that is integrally designed within an externally pressurized tilting-pad radial gas bearing support. The flexibly damped gas bearing module was designed for a 7.2″ (183 mm) diameter shaft and fabricated using direct metal laser melting (DMLM); also known as additive manufacturing. The bearing and HSFD were sized based on ongoing studies for oil-free supercritical carbon dioxide (sCO2) power turbines in the 8.5 MW–10 MW power range. The development of the new damper concept was motivated by past dynamic testing on HSFD, which generated frequency-dependent stiffness and damping force coefficients. In efforts to eliminate the frequency dependency, a new HSFD architecture was conceived that adds accumulator volumes and a pass-through channel to previously conceived HSFD flow network designs. The other motivation for the work is the need to develop a cost-effective and reliable oil-free bearing technology that is scalable to large power turbomachinery applications. There were several objectives for the following work. The first objective was to successfully design and fabricate a single piece bearing-damper using additive manufacturing, while dimensionally controlling critical design features. The paper discusses the manufacturing steps and shows cut-ups that reveal adequate clearance control capability with internal damper clearances. The second objective was to perform experimental testing with the new HSFD design in efforts to extract stiffness and damping coefficients for excitation frequencies within 20–160 Hz and peak vibration amplitudes between 0.25 mils (6.35 microns) to 1 mil (25.4 microns). The test results for a single HSFD bearing module indicated that the design modifications to the HSFD architecture were successful in eliminating nearly all the frequency dependencies for the stiffness force coefficient. The dynamic tests yielded a stiffness coefficient that varied between 112 klb/in. (19.6 MN/m) and 96 klb/in. (16.8 MN/m). The damping force coefficient however, exhibited relatively more variation with frequency with values residing between 175 lb-s/in. (31 kN-s/m) to 214 lb-s/in. (37 kN-s/m). Finally, the paper advances a three-dimensional fluid-structure interaction (FSI) model using transient finite element analysis (FEA) coupled to a computational fluid dynamics (CFD) model. The FSI analysis performed between 20 Hz and 80 Hz was used to predict the stiffness and damping of the HSFD using a quarter-section model of the damper. The FSI analysis was able to support test results by showing only a 6–7.4% change in the magnitude of force coefficients. Stiffness predictions agree reasonably well with experiments whereas damping is underpredicted.

Engineering↗

Correlation of Qualification and Accelerated Testing with Field Degradation

Qualification testing of solar photovoltaic (PV) modules per IEC 61215 standard encompasses a set of well-defined accelerated stress tests (irradiation, environmental, mechanical and electrical) with strict pass/fail criteria based on functionality/performance, electrical and mechanical safety, and visual requirements. The qualification testing does not identify all the possible reliability failures or durability issues witnessed in the actual field. However, it does identify the major/catastrophic design quality issues (infant mortality), which could occur early in a module’s field life. Unfortunately, in the industry, there is no consensus-based standard or protocol available to validate manufacturers’ warranty period claims based on the end-of-life wear-out failure mechanisms. Being able to predict the field degradation rates and lifetime using mode-specific accelerated tests on moderately field-aged modules, for example 10 years, for certain commonly occurring degradation modes would be a powerful contribution to all the stakeholders of the PV industry. There is a need to formulate guidelines to find the correlation of accelerated testing with field degradation for individual degradation modes observed in the field. Potential approaches to fulfill this need were experimented in this project and are presented in this report. Two of the most commonly seen degradation modes – encapsulant browning and solder bond thermomechanical fatigue – are addressed in this report through presenting the accelerated testing methods and physical modelling approaches. Two accelerated test methods (UV and thermal cycling) were designed to induce the wear-out mechanisms in the modules and not infant mortality failures. To focus on the wear-out failure modes, the tests were performed on field-aged modules, instead of fresh modules, with known degradation rates and degradation modes. The degradation rates were measured based on the degradation rates of individual cell parameters (short-circuit current, I sc and series resistance, R s ) instead of the degradation rate of maximum power (P max ) which cannot be used to study any specific/limited degradation mode as the P max degradation could be caused by many different degradation modes. The key characteristic parameter considered for encapsulant discoloration and solder bond degradation is I sc and R s , respectively. The developed physical models/equations relating the testing degradation data and field weather data were utilized to determine the acceleration factor (AF) and to predict the degradation rate for a specific degradation mode of PV modules installed in two different climates, Arizona (hot) and New York (cold). The predicted degradation rates for encapsulant browning and solder bond degradation have also been validated against the actual measured field degradation rates. UV testing cost reduction: To determine acceleration factor, single UV chamber was used for accelerated UV testing at three different temperatures simultaneously, instead of three chambers for three temperatures (or one chamber sequentially which is an extremely time-consuming approach). A passive heating approach was successfully used to achieve and maintain multiple temperatures in the accelerated UV chamber. Foam insulation boards of varying thicknesses were utilized to obtain three different temperatures for UV testing. However, these foam materials tend to disintegrate in the presence of moisture. To alleviate this problem, silicone heating blankets with temperature controls and humidifier can be used if the UV testing is to be performed under hot-humid conditions instead of conventional hot-dry conditions. Thermal cycling testing cost reduction: Single thermal cycling chamber was used for accelerated thermal cycling testing at three different upper temperatures simultaneously, instead of three chambers for three upper temperatures (or one chamber sequentially which is an extremely time-consuming approach). An active heating approach based on silicone heating blankets was successfully used to achieve and maintain multiple upper temperatures in the accelerated thermal cycling chamber. Such blankets provide stable temperature control and thereby more reliable and repeatable for replicate experiments.

14 SOLAR ENERGY↗

A General Approach for Lab‐to‐Manufacturing Translation on Flexible Organic Solar Cells

Abstract The blossoming of organic solar cells (OSCs) has triggered enormous commercial applications, due to their high‐efficiency, light weight, and flexibility. However, the lab‐to‐manufacturing translation of the praisable performance from lab‐scale devices to industrial‐scale modules is still the Achilles' heel of OSCs. In fact, it is urgent to explore the mechanism of morphological evolution in the bulk heterojunction (BHJ) with different coating/printing methods. Here, a general approach to upscale flexible organic photovoltaics to module scale without obvious efficiency loss is demonstrated. The shear impulse during the coating/printing process is first applied to control the morphology evolution of the BHJ layer for both fullerene and nonfullerene acceptor systems. A quantitative transformation factor of shear impulse between slot‐die printing and spin‐coating is detected. Compelling results of morphological evolution, molecular stacking, and coarse‐grained molecular simulation verify the validity of the impulse translation. Accordingly, the efficiency of flexible devices via slot‐die printing achieves 9.10% for PTB7‐Th:PC 71 BM and 9.77% for PBDB‐T:ITIC based on 1.04 cm 2 . Furthermore, 15 cm 2 flexible modules with effective efficiency up to 7.58% (PTB7‐Th:PC 71 BM) and 8.90% (PBDB‐T:ITIC) are demonstrated with satisfying mechanical flexibility and operating stability. More importantly, this work outlines the shear impulse translation for organic printing electronics.

Meng, Xiangchuan↗

High Efficiency Solar Integrated Roof Membrane Product

This project was designed to address the Solar Energy Technology Program objective, to develop new methods to integrate photovoltaic (PV) cells or modules within a building-integrated photovoltaic (BIPV) application that will result in lower installed cost as well as higher efficiencies of the encapsulated/embedded PV module. The technology assessment and development focused on the evaluation and identification of manufacturing technologies and equipment capable of producing such low-cost, high-efficiency, flexible BIPV solar cells on single-ply roofing membranes.

14 SOLAR ENERGY↗

Final Technical Report for CENTRIA's EnergyPeak Building Integrated Photovoltaics ( BIPV ) for Standing Seam Metal Roofing Project (DE-FG36-08GO88131)

Architects have said they will adopt Solar Roofs when they are integrated into roofing systems, building design, plans and specifications, and bidding procedures . Standing Seam Metal Roof manufacturers will answer these architects needs if someone will establish standards, pre-design systems, write specifications, tests systems, meet codes, etc. Energypeak was developed to provide the above so Architects can specify BIPV Standing Seam Roof Systems and Manufacturers can brand, market, sell, manufacture and deliver these systems. EnergyPeak took on the challenge to design BIPV modules using current PV technology, design electrical components, develop wire management systems, test, meet codes, write cad drawings and specifications, commercialize and deliver complete standards to the Industry.

14 SOLAR ENERGY↗

Modeling the Nonlinear Rheology of Polymer Additive Manufacturing

This report summarizes molecular and continuum simulation studies focused on developing physics - based predictive models for the evolution of polymer molecular order during the nonlinear processing flows of additive manufacturing. Our molecular simulations of polymer elongation flows identified novel mechanisms of fluid dissipation for various polymer architectures that might be harnessed to enhance material processability. In order to predict the complex thermal and flow history of polymer realistic additive manufacturing processes, we have developed and deployed a high - performance mesh - free hydrodynamics module in Sandia's LAMMPS software. This module called RHEO – short for Reproducing Hydrodynamics and Elastic Objects – hybridizes an updated - Lagrange reproducing - kernel method for complex fluids with a bonded particle method (BPM) to capture solidification and solid objects in multiphase flows. In combination, our two methods allow rapid, multiscale characterization of the hydrodynamics and molecular evolution of polymers in realistic processing geometries.

36 MATERIALS SCIENCE↗

The AMACStar ASIC for the HL-LHC ATLAS ITk Strip detector: design, verification, testing, and quality assurance

For the high-luminosity upgrade to the LHC (HL-LHC), the ATLAS detector at CERN requires an all-new inner detector, the Inner Tracker (ITk). The ITk Strip subdetector is made up of silicon modules, which include three types of radiation-hard ASICs. One of these is the Autonomous Monitor and Control (AMAC). The AMAC is manufactured by Global Foundries using 130 nm CMOS8RF DM technology and is approximately 3 by 5 mm in size. This ASIC autonomously monitors the temperatures, voltages, and currents in the module components while controlling critical values in order to prevent these quantities from reaching dangerous levels. The final design, AMACStar, was verified, tested, and ensured to perform all necessary functions. A quality control procedure using an in-house probe station set-up was developed in order to ensure that every individual chip on each wafer of AMACStars required by the ITk Strip project met performance requirements. The average per wafer yield of usable AMACStars is 92.33%, exceeding the design-specific 90% yield estimated for project costing. This estimate was based on actual yields for similar designs in this process.

Analogue electronic circuits↗

Life Cycle Assessment of Future Photovoltaic Electricity Production from Residential-scale Systems Operated in Europe

The photovoltaics (PV) industry is growing rapidly to meet the increasing demand of green power. As the industry grows, the manufacturing processes and the material and energy efficiencies of PV cells and panels are improving. To assess the impacts of this trend, future scenarios of single-crystalline (single-Si, also known as mono-crystalline) silicon and cadmium-telluride (CdTe) PV systems installed on European residences were established. Assessment of the improvement potential of PV electricity-generating technologies such as single-Si and CdTe could be considered in long-term energy strategy decisions. This study aims to provide scenario-based information about the environmental per-formance of single-Si and CdTe PV modules produced and operated in the far future (2030 to 2050). The deployment application assessed considers European residential roofs. We made scenario-dependent projections of key parameters for single-Si and CdTe PV panels manufactured in 2050. The parameters included cell efficiency, module efficiency, wafer thickness, cutting losses, kerf losses, silver use, glass thickness and operational lifetime. This study combines developments for these parameters with projections of the environmental performance of electricity mixes in the main manufacturing countries/regions (European Union, China and the United States of America) and with projections of the environ-mental performance of basic material production (aluminium, copper, magnesium, nickel, pig iron, zinc, clinker and flat glass) in the far future. The three scenarios used in the assessment of future PV electricity were categorized into three classes: 'business as usual' (BAU), 'realistic improvement' (REAL) and 'optimistic improvement' (OPT). It estimates the current life cycle greenhouse gas emissions of single-Si PV electricity produced on the roofs of European residences to be approximately 80 grams CO2-equi-valent per kWh (g CO2-eq per kWh). Based on the projected changes to key parameters and the background system, life cycle greenhouse gas (GHG) emissions could be reduced to 65% (scenario BAU), 31% (scenario REAL) and 18% (scenario OPT) of that value in the far future. Results for other life cycle assessment (LCA) metrics are also assessed in this study such as: non-renewable cumulative energy demand, acidification potential, human toxicity potential, photochemical ozone creation potential, particulate matter formation potential, and land use. We calculated the total energy payback time (EPBT) and the non-renewable energy payback time (NREPBT) in the far future of single-crystalline silicon-based PV panels operated in Europe by dividing the estimate of non-renewable cumulative energy demand of PV electricity for the given scenario by the non-renewable cumulative energy demand of the scenario-dependent national and regional non-renewable residual electricity mixes. The study estimates the payback time could be reduced from 2.4 years today to 1.7, 1.2 and 1.2 years (scenarios BAU, REAL and OPT, respectively) in the far future, based on the assumptions and projections in the analysis. It finally estimates the current life cycle greenhouse gas emissions of CdTe PV electricity produced on the roofs of European residences to be approximately 30 g CO2-eq per kWh. Based on the projected changes to key parameters and the background system, life cycle GHG emissions could be reduced to 70% (scenario BAU), 44% (scenario REAL) and 32% (scenario OPT) of that value in the far future.

14 SOLAR ENERGY↗

Improving Heat Conduction of Insulated Metal Substrate with Thermal Pyrolytic Graphite Core for SiC Power Module Packaging

TPG-core IMS concept was jointly explored in this study. Integrating high thermally conductive TPG graphite core into IMS is expected to simultaneously achieve high thermal conductivity from TPG and electrical functionalities from IMS. Nearly 2x thermal conductivity and 30% weight saving was demonstrated on TPG-core IMS compared to conventional Cu-core IMS. Significant junction temperature reduction (11°C) in steady state and power cycling was revealed by the thermal analysis as the result of improved thermal spreading in plane and through the thickness. The study also proved the manufacturability and compatibility of this TPG-core IMS structure to the existing IMS production and power module assembling. Finally, the integration of TPG and IMS paves a new packaging route to increase heat load, improve reliability, simplify module design and reduce assembling cost and number of steps.

36 MATERIALS SCIENCE↗

Compact Solid State Cooling Systems: Compact MEMS Electrocaloric Module

BEETIT Project: UCLA is developing a novel solid-state cooling technology to translate a recent scientific discovery of the so-called giant electrocaloric effect into commercially viable compact cooling systems. Traditional air conditioners use noisy, vapor compression systems that include a polluting liquid refrigerant to circulate within the air conditioner, absorb heat, and pump the heat out into the environment. Electrocaloric materials achieve the same result by heating up when placed within an electric field and cooling down when removed—effectively pumping heat out from a cooler to warmer environment. This electrocaloric-based solid state cooling system is quiet and does not use liquid refrigerants. The innovation includes developing nano-structured materials and reliable interfaces for heat exchange. With these innovations and advances in micro/nano-scale manufacturing technologies pioneered by semiconductor companies, UCLA is aiming to extend the performance/reliability of the cooling module.

ARPA-E↗

Measurements and Characterization (Revised) (Fact Sheet)

Capabilities fact sheet for the National Center for Photovoltaics: Measurements and Characterization that includes scope, core competencies and capabilities, and contact/web information for Analytical Microscopy, Electro-Optical Characterization, Surface Analysis, and Cell and Module Performance.

14 SOLAR ENERGY↗

Thermal processing to modulate surface chemistry and bulk charge distribution in nickel-rich layered lithium positive electrodes

The broader application of nickel-rich layered oxides as positive electrode materials for lithium-ion batteries has been hindered by their high manufacturing cost and inferior cycling stability. Thermal processing, which is integral to electrode materials manufacturing and fundamental in materials science, has not been fully utilized to design advanced positive electrode materials. Herein, we demonstrate the capability of using quenching heat treatment to regulate Li distribution and modulate electronic structure near particle surface. The resulting materials exhibit less parasitic reactions with the electrolyte and an improved charge distribution homogeneity in secondary particles, leading to more stable cycling performance at high voltages (4.5 V vs Li/Li + ). Our synchrotron X-ray analyses reveal the underlying interplay between surface structure and bulk charge distribution in positive electrode materials particles. While strategies used to stabilize positive electrode materials through compositional control, surface modification, and electrolyte engineering have become mature, thermal processing can be advantageous to further improve positive electrode materials manufacturing.

36 MATERIALS SCIENCE↗

Electronics Upgrades to the Green is Clean Phoswich Detector Systems and Programmatic Implementation at LANL - Phase II Completion - 18403

Los Alamos National Laboratory (LANL) radiological facilities produce low-density room trash that, in many cases, is not contaminated with radioactivity. It has been estimated that 50 to 90% of low-density room trash is free of radioactive contamination and eligible for inclusion in LANL's Green is Clean (GIC) program. The GIC program is a verification program for non-regulated waste from radiation controlled areas that has been actively segregated as nonradioactive through the use of the waste generator's acceptable knowledge. The GIC program has employed two large area Phoswich gamma ray detector systems (HERCULES and ZEUS) to verify that GIC candidate low-density waste contains no radioactivity above background. The large area (127 cm{sup 2}) Phoswich detectors consist of a thin NaI front crystal (3 mm thick) that is optically coupled to a thick CsI back crystal (50 mm thick). The scintillation properties of the two crystals are different enough to allow the system's electronic components to identify the origin of any pulse. The original systems utilize Nuclear Instrumentation Module (NIM) electronics to process the detector signals. The electronics currently in use by the systems are out of date and some components are no longer manufactured. In 2015, phase I upgrades to the GIC detector systems were completed. Phase I objectives included identifying more modern commercially available electronics that could replace the NIM electronics. A pulse shape discriminator (PSD) module, the Digital Gamma Finder (DGF) Pixie-4 made by XIA LLC, that fits in a compact National Instruments{sup TM} PXI chassis was identified to replace the majority of the original NIM bin electronics - a single Pixie-4 module replaces four NIM amplifiers and four NIM pulse shape analyzers (PSAs). Another phase I objective was to show that that new PSD could separate out the NaI and CsI detector signals in a manner equivalent to or better than the NIM electronics. Proof of concept was achieved in 2015 when a prototype upgrade system on ZEUS was built and tested and gating parameter settings were determined that successfully separated the NaI and CsI signals. Phase II required establishing a LabVIEW software interface with Pixie-4 electronics in lieu of the manufacturer provided Pixie-4 software called the Pixie Viewer. In addition, phase II included 1) final optimization of the gating parameters on the prototype Pixie-4 ZEUS system, 2) finalizing Requirements, Design and Test Plan documents, 3) LabVIEW software interface quality assurance (QA) testing, 4) setting up the HERCULES system with the Pixie-4 upgrade electronics, 5) check source and background calibration of both systems, 6) absolute efficiency determination on both systems and 7) procedure revisions and implementation of both systems into routine operations. In 2017 phase II was completed including the preparation of detailed Requirements, Design and Test Plan documents. The LabVIEW interface software that communicates and controls the Pixie-4 has been completed, merged with the preexisting LabVIEW operations software and fully tested. Gating parameter optimization, configuration of HERCULES with the Pixie-4 electronics, check source and background calibrations and absolute efficiency determinations have all been performed - quantitative results are presented in the full paper. For performance validation, comparison measurements of actual GIC bags on both the HERCULES system using the old NIM Bin electronics and the ZEUS system using the upgraded Pixie-4 electronics have been done and evaluated. Finally, procedure revisions and implementation of both systems into routine operations is currently in process and planned to be complete by the end of calendar year 2017. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Benchmarks of Global Clean Energy Manufacturing, 2014-2016

Benchmarks of Global Clean Energy Manufacturing provides an assessment of the global state of clean energy manufacturing over 3 years from 2014 to 2016. Four technologies were examined - wind turbine components (blade, tower, nacelle), crystalline silicon (c-Si) solar photovoltaic (PV) modules, light-duty vehicle (LDV) lithium-ion battery (LIB) cells, and light-emitting diode (LED) packages for lighting and other consumer products. The analysis looked along each technology's manufacturing supply chain, including processing raw materials, producing required subcomponents, and assembling final products. Manufacturing supply chains were evaluated across 13 economies that are the primary manufacturing hubs for these technologies. This Highlights summary report features key findings across the manufacturing supply chains.

42 ENGINEERING↗

Relating Product Prices to Long‐Run Marginal Cost: Evidence from Solar Photovoltaic Modules

Abstract A basic tenet of microeconomics is that for a competitive industry in equilibrium the market price of a product will be equal to its marginal cost. This paper develops a model framework and a corresponding empirical inference procedure for estimating long‐run marginal cost in industries where production costs decline over time. In the context of the solar photovoltaic (PV) module industry, we rely primarily on firm‐level financial accounting data to estimate the long‐run marginal cost of PV modules for the years 2008–2013. During those years, the industry experienced both unprecedented price declines and significant expansions of manufacturing capacity. We compare the trajectory of average sales prices with the estimated long‐run marginal costs in order to quantify the extent to which actual price declines were attributable to reductions in production costs. The trajectory of estimated product costs is then extrapolated to forecast an equilibrium trend line for future PV module prices.

Reichelstein, Stefan↗

Controlling shockwave dynamics using architecture in periodic porous materials

Additive manufacturing (AM) is an attractive approach for the design and fabrication of structures capable of achieving controlled mechanical response of the underlying deformation mechanisms. While there are numerous examples illustrating how the quasi-static mechanical responses of polymer foams have been tailored by additive manufacturing, there is limited understanding of the response of these materials under shockwave compression. Dynamic compression experiments coupled with time-resolved X-ray imaging were performed to obtain insights into the in situ evolution of shockwave coupling to porous, periodic polymer foams. We further demonstrate shock wave modulation or “spatially graded-flow” in shock-driven experiments via the spatial control of layer symmetries afforded by additive manufacturing techniques at the micron scale.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Agent-Based Modeling for the Circular Economy: Lessons Learned From Three Case Studies

The circular economy (CE) aims at decoupling human activities from resource use, creating wealth in the process. Recently, many scholars have questioned the link between increased circularity and sustainability, resulting in many methodological approaches being developed for that purpose. This presentation summarizes the insights gained from the application of agent-based modeling (ABM) to study the techno-economic and social conditions promoting circularity and sustainability of three technologies: photovoltaic (PV) modules, hard disk drives (HDDs), and wind blades. Four main categories of agents are defined in the ABM: asset owners, service providers (e.g., refurbishers), recyclers, and manufacturers. Two main CE strategies are represented: lifetime extension (through repair or reuse) and recycling. The developed models start by projecting installed capacities and end-of-life (EOL) quantities. Then the theory of planned behavior - a social psychology model explaining behavior adoption based on attitude, peer influence, and costs - is used to model the asset owners' EOL decision (i.e., landfill, recycle or extend the lifetime of the asset). Then, the quantities of assets flowing to the recycler and service provider agents and quantities of materials flowing to manufacturers are computed. Recyclers' economies of scale are dynamically modeled, and the value generated by the CE strategies for the recyclers, service providers, and manufacturers is computed within the model. When data are available, avoided greenhouse gas emissions resulting from the CE strategies adoption are calculated exogenously from the ABM simulations. Results show that with improved used PV modules warranties, the reuse CE strategy adoption increases from 1% to 23% between 2020 and 2050. Similarly, improved standards could enhance HDDs end-users trust in data-wiping - a prerequisite to reuse - leading to a 3-fold increase in the reuse rate and avoid about 5 million tons of CO2 eq by 2050. Regarding wind blades, 5-15 years lifetime extension could reduce EOL blade quantities by 13%. High costs and logistic issues prevent blades from being recycled in greater quantities. One insight from the case studies is the necessity to have mature secondary markets for reuse to be a viable option. Interestingly, PV reuse is limited by the willingness of PV owners to purchase used modules (on the demand side), while HDDs reuse is constrained by the lack of trust toward data-wiping (limiting the supply of used HDDs). The six limits of the CE concepts presented by Korhonen et al. (2018) are finally used to interpret the results. The HDD case study is an exemplary lock-in, where the first accepted practice (shredding) retains most of the market. The PV results illustrate the technical limitation to reuse, as the growing demand cannot be supplied entirely with used PV modules. The wind case study shows the relevance of clearly defining physical flows - what type of waste should wind blades be considered, how should they be transported and landfilled? - a crucial consideration that also applies to PV modules. Finally, the three case studies highlight the relevance of studying a technology's technical, economic, and market material efficiency potentials altogether and the potential benefit of coupling ABM to life cycle assessment.

agent-based modeling↗