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1.
Appl Opt ; 62(31): H9-H16, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38037918

RESUMO

A roadblock to long-term growth of the photonics industry is the availability of well-trained, adaptable middle-skilled workers. This research characterizes the middle-skilled workforce gap, including the quantity required and skills needed. We estimate that 42,000 new technical middle-skilled workers are needed by 2030, requiring another 100 technician programs nationwide. Training skills along the supply chain are critical; programs must emphasize testing, troubleshooting, and process design. Middle-skilled workers trained in critical thinking will enable an adaptable workforce capable of handling technology evolution. Finally, recommendations for the academia, industry, and middle-skilled training ecosystem are included to ensure that the latter evolves with technology development.

2.
Environ Sci Technol ; 55(14): 10097-10107, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34213890

RESUMO

Modern automobiles are composed of more than 2000 different compounds comprising 76 different elements. Identifying supply risks across this palette of materials is important to ensure a smooth transition to more sustainable transportation technologies. This paper provides insight into how electrification is changing vehicle composition and how that change drives supply risk vulnerability by providing the first comprehensive, high-resolution (elemental and compound level) snapshot of material use in both conventional and hybrid electric vehicles (HEVs) using a consistent methodology. To make these contributions, we analyze part-level data of material use for seven current year models, ranging from internal combustion engine vehicles (ICEV) to plug-in hybrid vehicles (PHEVs). With this data set, we apply a novel machine learning algorithm to estimate missing or unreported composition data. We propose and apply a metric of vulnerability, referred to as exposure, which captures economic importance and susceptibility to price changes. We find that exposure increases from $874 per vehicle for ICEV passenger vehicles to $2344 per vehicle for SUV PHEVs. The shift to a PHEV fleet would double automaker exposure adding approximately $1 billion per year of supply risk to a hypothetical fleet of a million vehicles. The increase in exposure is largely not only due to the increased use of battery elements like cobalt, graphite, and nickel but also some more commonly used materials, most notably copper.


Assuntos
Veículos Automotores , Emissões de Veículos , Automóveis , Eletricidade , Humanos , Meios de Transporte , Emissões de Veículos/análise
3.
Environ Sci Technol ; 53(18): 10560-10570, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31336049

RESUMO

Electrification and lightweighting technologies are important components of greenhouse gas (GHG) emission reduction strategies for light-duty vehicles. Assessments of GHG emissions from light-duty vehicles should take a cradle-to-grave life cycle perspective and capture important regional effects. We report the first regionally explicit (county-level) life cycle assessment of the use of lightweighting and electrification for light-duty vehicles in the U.S. Regional differences in climate, electric grid burdens, and driving patterns compound to produce significant regional heterogeneity in the GHG benefits of electrification. We show that lightweighting further accentuates these regional differences. In fact, for the midsized cars considered in our analysis, model results suggest that aluminum lightweight vehicles with a combustion engine would have similar emissions to hybrid electric vehicles (HEVs) in about 25% of the counties in the US and lower than battery electric vehicles (BEVs) in 20% of counties. The results highlight the need for a portfolio of fuel efficient offerings to recognize the heterogeneity of regional climate, electric grid burdens, and driving patterns.


Assuntos
Gases de Efeito Estufa , Emissões de Veículos , Automóveis , Gasolina , Efeito Estufa , Veículos Automotores
4.
Environ Sci Technol ; 51(24): 14436-14444, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29120610

RESUMO

A comprehensive component-level assessment of several strategic and minor metals (SaMMs), including copper, manganese, magnesium, nickel, tin, niobium, light rare earth elements (LREEs; lanthanum, cerium, praseodymium, neodymium, promethium, and samarium), cobalt, silver, tungsten, heavy rare earth elements (yttrium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium), and gold, use in the 2013 model year Ford Fiesta, Focus, Fusion, and F-150 is presented. Representative material contents in cars and light-duty trucks are estimated using comprehensive, component-level data reported by suppliers. Statistical methods are used to accommodate possible errors within the database and provide estimate bounds. Results indicate that there is a high degree of variability in SaMM use and that SaMMs are concentrated in electrical, drivetrain, and suspension subsystems. Results suggest that trucks contain greater amounts of aluminum, nickel, niobium, and silver and significantly greater amounts of magnesium, manganese, gold, and LREEs. We find tin and tungsten use in automobiles to be 3-5 times higher than reported by previous studies which have focused on automotive electronics. Automotive use of strategic and minor metals is substantial, with 2013 vehicle production in the United States, Canada, EU15, and Japan alone accounting for approximately 20% of global production of Mg and Ta and approximately 5% of Al, Cu, and Sn. The data and analysis provide researchers, recyclers, and decision-makers additional insight into the vehicle content of strategic and minor metals of current interest.


Assuntos
Automóveis , Metais , Canadá , Japão , Lantânio , Neodímio , Praseodímio
5.
Environ Sci Technol ; 50(14): 7687-95, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27285880

RESUMO

Platinum-group metals (PGMs) are technological and economic enablers of many industrial processes. This important role, coupled with their limited geographic availability, has led to PGMs being labeled as "critical materials". Studies of future PGM flows have focused on trends within material flows or macroeconomic indicators. We complement the previous work by introducing a novel technoeconomic model of substitution among PGMs within the automotive sector (the largest user of PGMs) reflecting the rational response of firms to changing prices. The results from the model support previous conclusions that PGM use is likely to grow, in some cases strongly, by 2030 (approximately 45% for Pd and 5% for Pt), driven by the increasing sales of automobiles. The model also indicates that PGM-demand growth will be significantly influenced by the future Pt-to-Pd price ratio, with swings of Pt and Pd demand of as much as 25% if the future price ratio shifts higher or lower even if it stays within the historic range. Fortunately, automotive catalysts are one of the more effectively recycled metals. As such, with proper policy support, recycling can serve to meet some of this growing demand.


Assuntos
Platina , Ródio , Automóveis , Catálise , Paládio
7.
Environ Sci Technol ; 46(23): 12986-93, 2012 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-23088692

RESUMO

Platinum is an excellent catalyst, can be used at high temperatures, and is stable in many aggressive chemical environments. Consequently, platinum is used in many current industrial applications, notably automotive catalytic converters, and prospective vehicle fuel cells are expected to rely upon it. Between 2005 and 2010, the automotive industry used approximately 40% of mined platinum. Future automotive industry growth and automotive sales shifts toward new technologies could significantly alter platinum demand. The potential risks for decreased platinum availability are evaluated, using an analysis of platinum market characteristics that describes platinum's geophysical constraints, institutional efficiency, and dynamic responsiveness. Results show that platinum demand for an automotive fleet that meets 450 ppm greenhouse gas stabilization goals would require within 10% of historical growth rates of platinum supply before 2025. However, such a fleet, due largely to sales growth in fuel cell vehicles, will more strongly constrain platinum supply in the 2050 time period. While current platinum reserves are sufficient to satisfy this increased demand, decreasing platinum ore grade and continued concentration of platinum supply in a single geographic area are availability risk factors to platinum end-users.


Assuntos
Automóveis , Platina/provisão & distribuição , Catálise , Platina/química , Tecnologia
8.
Environ Sci Technol ; 46(6): 3406-14, 2012 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-22304002

RESUMO

The future availability of rare earth elements (REEs) is of concern due to monopolistic supply conditions, environmentally unsustainable mining practices, and rapid demand growth. We present an evaluation of potential future demand scenarios for REEs with a focus on the issue of comining. Many assumptions were made to simplify the analysis, but the scenarios identify some key variables that could affect future rare earth markets and market behavior. Increased use of wind energy and electric vehicles are key elements of a more sustainable future. However, since present technologies for electric vehicles and wind turbines rely heavily on dysprosium (Dy) and neodymium (Nd), in rare-earth magnets, future adoption of these technologies may result in large and disproportionate increases in the demand for these two elements. For this study, upper and lower bound usage projections for REE in these applications were developed to evaluate the state of future REE supply availability. In the absence of efficient reuse and recycling or the development of technologies which use lower amounts of Dy and Nd, following a path consistent with stabilization of atmospheric CO(2) at 450 ppm may lead to an increase of more than 700% and 2600% for Nd and Dy, respectively, over the next 25 years if the present REE needs in automotive and wind applications are representative of future needs.


Assuntos
Metais Terras Raras/provisão & distribuição , Conservação dos Recursos Naturais , Fontes de Energia Elétrica , Mineração
9.
Environ Sci Technol ; 45(9): 4118-26, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21466183

RESUMO

The increased use of secondary (i.e., recycled) and renewable resources will likely be key toward achieving sustainable materials use. Unfortunately, these strategies share a common barrier to economical implementation - increased quality variation compared to their primary and synthetic counterparts. Current deterministic process-planning models overestimate the economic impact of this increased variation. This paper shows that for a range of industries from biomaterials to inorganics, managing variation through a chance-constrained (CC) model enables increased use of such variable raw materials, or heterogeneous feedstocks (hF), over conventional, deterministic models. An abstract, analytical model and a quantitative model applied to an industrial case of aluminum recycling were used to explore the limits and benefits of the CC formulation. The results indicate that the CC solution can reduce cost and increase potential hF use across a broad range of production conditions through raw materials diversification. These benefits increase where the hFs exhibit mean quality performance close to that of the more homogeneous feedstocks (often the primary and synthetic materials) or have large quality variability. In terms of operational context, the relative performance grows as intolerance for batch error increases and as the opportunity to diversify the raw material portfolio increases.


Assuntos
Manufaturas/economia , Reciclagem/economia , Alumínio/química , Animais , Colágeno/química , Gelatina/química , Modelos Teóricos , Papel , Reciclagem/tendências , Borracha/química
11.
Environ Sci Technol ; 41(19): 6649-56, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17969676

RESUMO

Many authors suggest that market forces are inadequate to successfully manage the problems of resource availability and use. The fundamental question is whether these inadequacies are intrinsic to the market or if they arise from a failure of firms to detect and respond to subtle market signals. This paper explores the latter by describing (1) mechanisms that can limit materials availability, (2) effects of such limits on the firm, (3) preliminary metrics to diagnose these risks, and (4) strategies to reduce a firm's risk exposure. Case analyses of two materials systems are used to suggestthat private firm interests, when properly informed, can motivate strategies that drive toward sustainable materials use. These strategies include (1) improving production efficiency, (2) developing technology to use more sustainable substitute materials, and (3) facilitating a more effective materials recycling infrastructure.


Assuntos
Comércio , Conservação dos Recursos Naturais , Cobalto/economia , Cobre/economia
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