VANCOUVER (miningweekly.com) – Global copper mine production growth is expected to slow to 2.5% a year through 2020, down from an average growth rate of almost 4% a year in the last five years, the International Copper Study Group (ICSG) said on Thursday.

The Lisbon, Portugal-based think tank cited continued delays in project development as shifting new capacity forward, owing mainly to length of project permitting, opposition from local communities and budget or finance constraints.

The ICSG expects concentrates will represent around 90% of the total growth in world mine production capacity until 2020, with Chile, China, the Democratic Republic of the Congo (DRC), Peru and Zambia together representing 55% of the new copper mine capacity to be brought on stream.

Production capacity from countries that started mining copper in the last decade is seen as increasing from zero in 2000, to about 420 000 t/y by 2020.

Several countries that currently do not mine copper, including Afghanistan, Ecuador, Ethiopia, Fiji, Greece, Israel, Panama, Sudan and Thailand will also contribute to world copper supplies by 2020, with new projects in the pipeline. The total expected copper production capacity from projects starting in these countries could reach 330 000 t/y, and capacity could continue to increase well above one-million tonnes a year if projects under evaluation in these countries are developed, the group said in a news release.

Meanwhile, increased interest in seabed copper exploration will also add a new supply stream, with several projects being evaluated. The first such project is expected to start production in 2019, in the Bismarck Sea, off Papua New Guinea.

Through 2020, yearly copper smelter production capacity might grow at an average rate of around 1.7%, compared with an average capacity growth rate of almost 3% a year in the last five years.

The ICSG said China is continuing to expand its smelting capacity, albeit at a slower pace than before. China’s copper smelting capacity more than quintupled in the period from 2000 to 2016, and is expected to increase by a further 20% until 2020, accounting for 80% of the forecast world growth in smelting capacity by then.

Outside of China, new copper smelters are planned to be built in the DRC, India, Indonesia, Kazakhstan, Mexico and Mongolia, but only beyond 2020.

Yearly copper smelter capacity growth is projected to lag the growth in concentrate capacity. The balance between concentrate production and available smelting capacity will depend on capacity utilisation rates.

Through 2020, yearly copper refinery output capacity might also grow at an average rate of around 1.2%, compared with an average capacity growth rate of 3% a year in the last five years, the ICSG said.

About 80% of this growth through 2020 is expected to come from electrolytic refineries. Electrolytic refinery capacity growth is projected to average 1.5% a year and is generally tied to the growth of smelter capacity.

About 65% of the increase in world refinery capacity during this period is expected to come from electrolytic refineries in China, and about 18% from electrowinning capacity increases in the DRC. Electrowinning capacity is expected to decline by 15% in Chile, the world’s biggest producer of the red metal, through 2020.