Answer developed by Denzil Walton
The shift towards renewable energy sources and electric vehicles is going to require the use of more copper than is currently being used. Does the planet have enough copper? We consider the past, present and future role of copper
The historical perspective
Copper has been around for ages — literally, because it even has its own Age. The Copper Age lasted from around 4500 to 3500 BCE, when human societies began widely using copper to make agricultural and construction tools, as well as weapons. Then someone, maybe accidentally, mixed tin with copper to discover a new material even stronger than copper. The Bronze Age was born, although of course copper remained the key ingredient.
The influence of copper has remained strong through the centuries. Its ductility, which led to its use in ancient Egyptian water pipes, is illustrated by its abundance in plumbing and heating systems. Its corrosion resistance induced the Romans to use it to sheath the roof of the Pantheon, and is the reason why thousands of modern buildings have copper roofs. Its excellent conductivity (second only to silver) means it has always been the conductor of choice, the standard material for electrical wiring systems, and the key to modern power generation, where it contributes to applications as diverse as solar heating, large-scale desalination of water, and electric motor innovations.
The energy transition
However, times are changing — fast. The energy transition, defined as the shift from a system dominated by finite (chiefly fossil-based) energy towards a system using a majority of renewable sources, is going to have a certain impact on copper usage. Basically, we are going to need more copper than we use at present.
Renewable energy generation technologies, especially wind, ocean and solar installations, are copper-intensive. The installation of 1 MW of offshore wind energy requires about 6 tons of copper. A photovoltaic plant requires about 4 tons/MW, appreciably more than an oil-fired power plant (1.1 ton/MW) or a nuclear power plant (0.7 ton/MW).
The changing energy system will also require more investments in the transmission and distribution infrastructure, leading to greater use of copper in grids, transformers, power electronics, and even possible cross-border transmission lines.
Then there’s the matter of how this renewable energy will be used in the decades to come. A typical medium-sized electric vehicle, for example, contains around 83 kg of copper, compared to around 23 kg of copper in a comparable car powered by an internal combustion engine.
The important role of energy efficiency in the energy transition will also have an impact on copper use. The increasing use of heat pumps and industrial electric heat will require more copper, as will near-zero energy buildings, building automation systems, demand response, and energy storage solutions.
Combining all these applications, it is estimated that by 2050, the EU additional cumulative demand will revolve around 25 million tons of copper. While the absolute amount is relevant, it is spread over 3 decades, meaning an average annual increase of about 15% over current EU demand levels.
How much copper is available now — and in the future?
Any figures pointing to the amount of copper available in the world are based on the concept of reserves and resources:
- Copper reserves are deposits that have been discovered, evaluated and assessed to be profitable; they amount to 720 million tonnes 
- Copper resources are far larger because they include the already discovered reserves, plus predicted unexploited deposits based on geological surveys. They are estimated to exceed 5,000 million tonnes .
In addition, current and future exploration opportunities will increase both reserves and resources. For example, the total resources above do not include the vast copper deposits found in deep-sea nodules and submarine massive sulphides.
In other words, there would seem to be adequate copper resources available to cover the increased usage of copper due to the energy transition.
However, these figures don’t give the total picture, because there is a key property of copper that also has to be taken into consideration, and which is likely to play a significant role in the energy transition …
Copper is highly recyclable
We are all used to the concept that metals can be recycled, but the trump card of copper is that it is one of the few materials that can be recycled repeatedly without loss of performance. There is also no difference in the quality of recycled copper (secondary production) and mined copper (primary production). Depending on market conditions, lower-grade coppers can even be upcycled to electrical conductivity applications, if entered back early enough in the production process.
The recycling of copper is also energy efficient - bulk copper applications require 85% less energy than primary production. The infrastructure is well in place too; during the last decade about half of the EU’s annual copper use came from recycled sources (and is increasing).
It is estimated that two-thirds of the 550 million tonnes of copper produced since 1900 are still in productive use . This enormous stock of copper, contained in its diverse range of end uses, is equivalent to around 30 years of mining production.
Copper is not cobalt or indium …
… nor is it tantalum, niobium or rare earths. These and up to 27 other elements have been denoted by the European Commission as critical raw materials, defined as metals whose availability is essential for high-technology, green or defence applications, but which are vulnerable to politically or economically driven fluctuations in supply.
The applications areas, supply market and mine to end-user pathways of these metals have undergone major changes in the past few decades. These have significantly affected their prices, or raised concerns about the future of advanced technologies that depend upon them.
Copper is not a critical metal, it never has been, and considering its resources and recyclability, is not likely to become one. It’s traded on the London and other Metal Exchanges, where its price is set on a daily basis through market mechanisms.
Moreover, copper reserves are well distributed in many regions of the world, hence are not dependent on any particular country or economy, whereas the reserves of many rare-earth elements are often located in a limited number of countries. This can lead to price volatility and issues surrounding security of supply.
Even with the increased demand for copper due to the energy transition, the resources of copper on this planet, coupled with its recyclability, clearly support the long-term availability of copper for current and forthcoming applications.
While every material has its challenges, copper is an established commodity with a firmly established value chain, including a well-organised recycling chain.
The sustainability of copper is good and is continually improving. It’s a driver of the circular economy and serves as recycling motivator due to its intrinsic value (economics driven) and the fact that it serves as carrier metal (e.g. for precious metals), which enables higher value recycling.
Is there enough copper for the energy transition? It certainly looks as if there is.
● History of copper use http://j.mp/CuHistory
● Long-term availability of copper http://j.mp/CuLTAv
● Copper & recycling http://j.mp/CuRecycling
● London Metal Exchange: https://www.lme.com/
 U.S. Geological Survey, Mineral Commodity Summaries, February 2017
 U.S. Geological Survey, Mineral Commodity Summaries, January 2016