The 256 panels, tethered to the bottom of the artificial lagoon to ensure proper orientation even in strong winds and changing water levels, have the capacity to produce 86 kilowatts, the company said.

Chile mining minister Baldo Prokurica, who attended a ceremony inaugurating the project, said he saw the pilot programme, the first of its kind, according to Anglo American, as a model to follow.

"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."

Global miners are increasingly seeking innovations to boost efficiencies, lower costs and reduce use of water at mines. In Chile, the world's top copper producer, that has largely meant a turn to solar power and desalinated sea water.

Los Bronces' high altitude location on the outskirts of heavily populated Santiago has forced the company to seek alternatives. Tailings from the production of copper at the mine are piped 57 kilometres (35.4 miles) to the lower-altitude pond, where they can be reused in industrial processes.

The pond's newly installed solar panels, besides generating electricity, also aid in reducing evaporation of water, improving efficiencies, according to the company.

Los Bronces produced 370,000 tonnes of copper in 2018.

(Reporting by Fabian Cambero, writing by Dave Sherwood; Editing by Susan Thomas)

By Fabian Cambero