Can aluminium replace much of the new demand for copper in the global energy transition?At present,many companies and industry scholars are exploring how to better"replace copper with aluminum",and propose that adjusting the molecular structure of aluminum can improve its electrical conductivity.

　　Due to its excellent electrical conductivity,thermal conductivity and ductility,copper is widely used in various industries,especially concentrated in electric power,construction,household appliances,transportation and other industries.But demand for copper is soaring as the world shifts to greener sources of energy,such as electric cars and renewable energy.An electric car,for example,uses about four times as much copper as a conventional car,and much more is needed for the electrical components used in renewable power plants and the wires that connect them to the grid.

　　Analysts at Wood Mackenzie,the energy consultancy,estimate that offshore wind farms will need 5.5m tonnes of copper over the next decade,mainly for large cable systems inside generators and for transporting electrons from turbines to shore.As copper prices have soared in recent years,some analysts have predicted a growing shortfall,with Goldman Sachs analysts calling copper"the new oil".With copper crucial to decarbonisation and renewable energy,the market faces a supply crunch that could push prices up more than 60%in four years.By comparison,aluminum,the most abundant metal element in the earth's crust,is about a thousand times more abundant than copper,and because it weighs much less,it is also more economical and convenient to mine.In recent years,some companies have used aluminum as an alternative to rare earth metals through technological innovation.Manufacturers of everything from electricity and air conditioners to auto parts have saved hundreds of millions of dollars by adopting aluminum instead of copper.Saudi Power has said it has saved 2.4 billion Saudi riyals($640 million)by replacing copper with aluminum in its medium-voltage distribution network.In addition,high-voltage power lines can be extended over longer distances by using aluminum wires that are both economical and lightweight.

　　However,Jonathan Barnes,chief copper analyst at Wood Mackenzie,said the"aluminium for copper"trend had slowed.In a wider range of electrical applications,aluminium's conductivity is the main constraint,with only two-thirds of that of copper.

　　Researchers at the Pacific Northwest National Laboratory(PNNL)are working to improve aluminum's electrical conductivity and make it more marketable than copper.The researchers believe that changing the structure of the metal and introducing the right additives can indeed affect its conductivity.If fully realized,the experimental technology,which could generate superconducting electricity,could play a role in markets beyond power lines,transforming areas such as cars,electronics and power grids.

　　"If you can make aluminum more conductive,even 80 or 90 percent as conductive as copper,aluminum could replace copper,and that would be a huge shift.Because it conducts electricity better,it's lighter,it's cheaper and it's more abundant."PNNL materials scientist Keerti Kappagantula believes conductivity is key.With the same conductivity as copper,lighter aluminum wires could be used to design lighter motors and other electrical components that allow cars to travel longer distances."Anything that runs on electricity can be made more efficient,from car electronics to energy production to transferring energy through the grid to your home to charge your car batteries."

　　The PNNL researchers used a process called solid state manufacturing,which uses shear forces and friction at lower temperatures to insert the new carbon material into the metal.At the same time,aluminum becomes more elastic at this temperature,which allows the researchers to control the distribution of the material and verify the distribution using computer simulations of the atomic structure of the new aluminum alloy.Mr Kappagantula says it is worth reinventing the two-century-old aluminium process.

　　In the future,the research team will use the new aluminum alloy to make wires,rods and sheets,and pass a series of tests to make sure it is more conductive and strong and flexible enough for industrial use.If those tests pass,the team says it will work with manufacturers to produce more aluminum.