Los Bronces mine

Floating solar island to lessen mine’s environmental impact

Image credit: reuters

Floating solar panels are being tested as a way to power operations at a huge mine in Chile and reduce water loss at the site.

Mining forms an important part of the country’s economy but typically uses huge amounts of electricity and water.

Mining company Anglo American is trialling the tech at its Los Bronces mine, as the government pushes to put Chile at the forefront of renewable energy use in Latin America and the world.

The 256 solar panels are tethered to the bottom of an artificial lagoon to ensure proper orientation even in strong winds and changing water levels. They are able to produce around 86kW kilowatts, the company said.

The 1,200-square-foot (110m2) array of solar panels was inaugurated by mining minister Baldo Prokurica.

 Los Bronces mine

Image credit: reuters

Officials said that if the test is successful, the £190,000 plant could be expanded to cover 40 hectares, or nearly 100 acres.

“I hope that, in practice, it extends to other [mines] in the country,” Prokurica told Reuters. “It’s an excellent alternative for generating energy and making better use of water.”

The array floats in the middle of a pond used to contain the refuse from mining, known as tailings, and it is expected that its shadow will lower the water temperature and reduce evaporation by 80 per cent.

This means the mine would retain more of that water for its operations and could reduce the amount of fresh water it pumps in a dry mountainous region where it is a scarce commodity.

“With this system, we can make our fresh water consumption more efficient, in line with our goal of re-imagining mining and reducing Anglo American’s fresh water consumption by 50 per cent by 2030, as well as the CO2 emissions by producing non-polluting energy,” said Patricio Chacana, Los Bronces’ vice president of operations.

If the year-long experiment works as planned, the solar panel island could be expanded and new ones could be installed at other mining ponds. Experts say there are approximately 800 such ponds in Chile.

“It is an excellent idea for the traceability of the mining industry and especially in terms of more efficient use of water. This is a company that recycles 76 per cent of the water it uses in its processes,” the mining minister said at the unveiling, and he encouraged other mining companies to follow suit.

Prokurica said the Mining Ministry is working on a plan to improve the safety of mine holding ponds, to guard against failures such as one at an iron ore mine recently in Brazil that unleashed a wall of mud that killed at least 186 people and polluted hundreds of miles of river.

Many of the tailing ponds in the north of the country are near urban centres.

Los Bronces is about 3,500m above sea level and 65 km from the country’s capital Santiago. The mine produced 370,000 tons of fine copper and 2,421 tons of molybdenum last year.

Almost 20 per cent of the energy produced and used in Chile comes from renewable sources, up from 6 per cent in 2013.

The global mining industry is increasingly looking at ways to boost efficiency in its operations in order to lower costs and reduce use of water. Chile is the world’s top copper producer and the sector is turning towards solar power and desalinated sea water to achieve those aims.

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