According to industry experts, the next generation of electric vehicles (EVs) from Tesla and others are being constructed for efficiency in a way that reduces copper content, modifications that could limit demand growth for the metal.

According to two recent projections, innovation in EVs has shown out to be a limiting factor, despite the rapid ramp-up in EV sales, driven by growth in China, which implies copper consumption will continue to increase for the rest of the decade.

Due in part to the wiring required for electric cars, copper has been viewed as a green energy transition bet. EVs can consume up to 80 kg (176 pounds) of copper, which is four times more than what is typically consumed in a car with a combustion engine.

In a research released this week, Goldman Sachs claimed that EVs were responsible for two-thirds of the increase in copper demand worldwide in 2017.

However, EV and battery manufacturers have discovered ways to reduce weight and prices, which also mean less copper is needed per car, according to separate reports from Goldman Sachs and consultancy CRU Group.

Between now and 2030, the CRU Group revised its prediction for the average EV's copper consumption down to 51-56 kg. It had previously predicted 65-66 kgs for the same period, which was less.

By 2030, Goldman Sachs predicted that the average amount of copper in an EV would drop to 65 kg, down from their previous prediction of 73 kg.

Both referred to a series of engineering modifications intended to increase the range, lighten the load, and boost the efficiency of EVs, all of which will reduce the overall copper content.

The engineering changes include switching to higher voltage systems that will require less wiring, using thinner copper foil in battery cells, and moving to more compact batteries where cells do not need to be linked into modules.

The major threat to copper's EV demand leverage, according to Goldman Sachs, is innovation in batteries and a potential switch to higher voltage systems like Tesla's.

It anticipates a 1 million metric ton demand for copper for EVs this year and a 2.8 million ton demand by 2030. 3.2 million metric tons of demand from EVs was previously predicted to exist in 2030.

However, EV adoption is increasing, making up for each unit's reduced copper usage.