LONDON, June 30 - A sharp rise in copper prices to record levels earlier this year has increased pressure on industrial users to consider aluminium as an alternative conductor across several sectors. The economic and physical trade-offs between the two metals - price, weight, conductivity and retooling costs - are shaping decisions for automakers, cable manufacturers, utilities and heating, ventilation and air conditioning (HVAC) suppliers.
Why companies weigh substitution
Both copper and aluminium transmit electricity and heat, but their relative cost and material properties determine whether companies adopt one over the other. Aluminium currently trades at roughly a quarter of copper's price, making it a compelling option when raw material costs are a dominant consideration. However, aluminium conducts electricity at only 61% of copper's efficiency, which typically requires aluminium conductors to be about 1.6 times the cross-sectional area of equivalent copper conductors.
Industry sources cited a common commercial threshold for reconsidering materials: companies tend to evaluate swaps when the copper-to-aluminium price ratio reaches between 3.5 and 4.0 or higher. That ratio climbed to a record 4.3 in January and at the time of reporting sat at about 4.2. Firms also factor in the expense of retooling manufacturing lines or changing design specifications, so any move to substitute follows detailed analysis rather than an immediate reaction to spot prices.
Weight considerations give aluminium another advantage. Copper is about 3.3 times heavier than aluminium. That weight delta makes aluminium attractive for vehicle applications - and particularly for battery electric vehicles (BEVs) - where reducing mass can measurably extend driving range.
Automotive examples
Use of aluminium in vehicle structures has long been established, but replacing copper wiring with aluminium is a more recent development. Several manufacturers and suppliers are now incorporating aluminium conductors in production models or evaluating them for future vehicles.
Ferrari reported that after deploying aluminium for engines and chassis, it began using aluminium wiring on its 296 model last year. The company said that, when combined with reduced cable cross-sections, the change cut total wiring weight by 15% to 20%.
BMW said it first introduced aluminium conductors in 2011 on its subcompact 1 Series and has progressively expanded substitution across hybrids and BEVs. Since launching its sixth-generation eDrive architecture last year, BMW reported it now uses a significant number of aluminium cables in both high- and low-voltage systems.
An industry source told Reuters that Stellantis has been switching wiring from copper to aluminium, though the automaker declined to comment publicly.
Tesla has been an early adopter of aluminium in multiple ways: the company advanced large aluminium casting techniques for chassis simplification and moved to aluminium wiring in its Model Y in 2019, with further use noted more recently in the Cybertruck.
Some Chinese EV manufacturers are also part of the trend. AVATR, XPeng and Xiaomi were identified by U.S. teardown consultancy Caresoft as using aluminium electrical wiring in new models to save on cost and weight; those three firms did not respond to requests for comment.
Toyota said it continually evaluates materials and may substitute aluminium for copper depending on the application, but it declined to provide specific details. Volkswagen told reporters it has no concrete plans for broad replacement of copper with aluminium for wiring, while noting aluminium is used where it offers distinct benefits.
Power cables and grid investment
Substitution has already occurred to a meaningful degree in the cable sector, yet large-scale investment in electricity networks is expected to drive continued demand for both metals. French cable maker Nexans estimated global grid investment of around 0 trillion by 2030 and anticipates growth for both copper and aluminium. Nexans sees copper remaining the benchmark for demanding applications, while aluminium should capture a growing share of grid projects due to its lower cost and greater availability.
Prysmian, the world's largest cable manufacturer based in Italy, said it has observed gradual substitution by customers. The company currently uses approximately 40% aluminium by weight - up 3 percentage points over the last five years - and 60% copper. Prysmian highlighted expectations for growth in areas such as grid resilience and data centres, which will drive demand for both materials.
At the distribution level, Energy Queensland - the state-owned operator Energy Queensland (Energex) - has been replacing copper with aluminium across its 210,000 km network for many years as components reached the end of their service life. Spokesperson Emma Oliveri said the utility finds aluminium more cost-effective, equally durable, lighter and able to span longer distances when stringing power lines.
Heating and air conditioning
HVAC manufacturers have also been substituting aluminium in heat exchange components as an approach to reduce costs and to address corrosion considerations in certain environments. Daikin Industries stated in its 2025 annual report that it is "maximizing cost reductions by switching from copper to aluminium," though the company did not provide further detail when asked.
Lennox International developed technology to use aluminium coils in air conditioners, heat pumps and evaporator coils. The company says the approach reduces potential corrosion and can lower the weight of units by as much as 50 lbs.
Carrier Global reported that since 2023 it has adopted aluminium coil technology across all of its coastal air conditioning and heat pump models to improve resistance to corrosion.
Commercial calculus and practical constraints
Across sectors, the move from copper to aluminium is not uniform. Where high conductivity, compact designs or specific performance characteristics are essential, copper remains the preferred material. Where cost pressures, weight savings or material availability are primary drivers, aluminium is gaining share.
Companies must also weigh the costs to modify production tooling and designs. Retooling can be material and is part of the reason many firms only adopt aluminium after a careful business case is made rather than in response to short-term price movements.
As market participants evaluate materials choices, the copper-to-aluminium price ratio, durability requirements, application-specific performance and the scale of required design changes will continue to inform substitution decisions across autos, power infrastructure and HVAC systems.