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Copper substitutability might be about 60% or more of current copper use

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Abstract

In their paper about the future availability of copper Henckens and Worrell (2020) assumed that not more than 10% of copper use can be substituted. Here it is argued that currently available data suggest that Cu substitutability might be about 60% or more of current copper use.

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... Unfortunately, there is no systematic and comprehensive overview of substitutability for any precious metal, or in our particular case, for copper (Reijnders, 2021). ...
... At the same time, the advantage is that power cables carry the same current at a lower weight at a significantly lower cost. Reijnders (2021) also agrees to replace copper in certain industries while opposing Henckens & Worrell (2020), who disagree with the substitutability of copper in electricity transmission. ...
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Copper and aluminium prices have long been influenced mainly by non-renewable resources and the industry's widespread use of copper and aluminium for their desired properties. Metal commodities are irreplaceable for the industry of developed countries, and their shortage in the covid times also increases the price and consequently the price of products made from them. As copper ore stocks continue to decline, suitable substitutes should be sought. The paper discusses the potential of copper substitution by aluminium and subsequently the development of prices and production of copper and aluminium, including a prediction about the future development. Research data were obtained from Market. business insider (2021) and Investing.com (2022) converted to time series. The price is shown in US dollars per tonne and the production value in millions of tonnes. Development data were processed using artificial intelligence and recurrent neural networks, including the Long Short Term Memory layer. Neural networks, as such, have great potential to predict these types of time series. The annual copper and aluminium production data were processed using a regression function. Neural networks could not be used due to the smaller data range. The results show that the 1NN30L neural network with an LSTM layer and considered a 30-day delay is the most suitable network for forecasting future copper prices, and the 3NN30L neural network with an LSTM layer and considered a 30-day delay is the most suitable network for forecasting future aluminium prices. The forecast has confirmed that the price of copper will fall at the end of 2021, and the trend will be constant in the next planned period. Aluminium will also fall sharply at the end of 2021; at the beginning of 2022, the price level is predicted to rise to that of 30 October 2021, and thereinafter the trend will be almost constant. Research has confirmed that copper and aluminium may be imperfect substitutes in some respect, but they can generally be considered complementary. Copper mining has stabilised in recent years, but aluminium production has increased significantly in the last decade, and it can be expected to grow in the near future.
... Apart from very small-sized applications such as in chips for electronics, aluminium (Al) alloys can be commercial substitutes for copper in wiring for electricity transport (Reijnders 2021). Al mining and processing is characterized by long-lasting negative impacts on the provision of ecosystem services (Tost et al. 2020), persistent soil pollution (Pokhrel and Dubey 2013;Farjana et al. 2019) and large inputs of fossil fuels (Zhang et al. 2016;Mansilha et al. 2019), which negatively impact natural capital to be transferred to future generations. ...
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Substitutability of natural capital by human-made capital would seem to be limited. When human-made capital substitutes natural capital, there are currently commonly long-lasting negative impacts of such substitutions on constituents of natural capital. Long-lasting negative impacts on natural capital can be considered at variance with justice between the generations. In view thereof, there is a case to define (environmental) sustainability as keeping natural capital intact for transferral to future generations. A major problem for such conservation regards natural resources generated by geological processes (virtually non-renewable resources), especially regarding geochemically scarce elements. Substitution of virtually non-renewable resources by generating equal amounts of renewables has been proposed as a way to conserve natural capital. However, renewables substituting for fossil carbon compounds are currently associated with negative impacts on constituents of natural capital to be transferred to future generations. The same holds for the substitution of widely used geochemically scarce virtually non-renewable copper by abundant resources generated by geological processes. Though current negative impacts of substitutions on natural capital can be substantially reduced, their elimination seems beyond the scope of what can be achieved in the near future. The less strict “safe operating space for humanity”, which has been used in “absolute sustainability assessments” is, however, not a proper alternative to keeping natural capital intact for transferral to future generations.
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Suitable permanent connectors are required for use with branch circuit aluminum wire in homes. Some connection devices that have been marketed as suitable for use with aluminum wire are prone to deteriorate with time under conditions of normal use, leading to instances of hazardous overheating. The literature and experimental evidence discussed in this paper soundly support the position that, from a safety standpoint, the only acceptable aluminum connection devices for permanent residential installation are those that show no resistance increase under both normal and accelerated test conditions.
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Adopting an evolutionary perspective, this paper argues that path dependence plays a major role in material use and substitution such that it might delay or even prevent substitution despite the occurrence of significant relative price changes. After elucidating the importance of material substitution from an ecological-economic point of view and after explaining the meaning of path dependence from an evolutionary perspective, the copper–aluminum material substitution process is described for the main electrical conductor producing countries—the US, Germany, and Japan. This example makes clear that irrespective of attractive relative prices in favor of aluminum it could neither achieve a predominant market position nor is it possible to identify an explicit relation between relative price changes and relative material use in a qualitative analysis. Applying a Distributed Lag Model for data on copper and aluminum for electrical applications, the significance of relative prices and path dependence is examined for a 51-year time period for the US, Japan, and Germany. The results indicate that path dependence and relative prices—especially in the long run—are both important factors influencing the copper–aluminum substitution process. The major conclusions read that substitution processes cannot be predicted by relative price movements alone and that price instruments to encourage material substitution should not be overestimated. Instead, in the design of resource policies it should be considered that material substitution is an evolutionary and path-dependent process, which requires learning as well as time, capital, research, and experience.
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