The PPA would cover 12% of the power requirements at Collahuasi, which is the second-largest copper mining operation in Chile and the sixth-largest worldwide.
"This agreement represents a new milestone for Collahuasi, allowing us to consolidate our transition to 100% green electricity and the search for sustainable operations throughout our value chain," said Jorge Gomez, chief executive of Collahuasi.
The mine's industrial facilities and the Rosario and Ujinaa mines are located in the commune of Pica, Tarapacá Region, where Sonnedix is constructing Sonnedix Atacama Solar - a 170 MegaWatt solar PV plant.
"It highlights our commitment towards the environment, the development of opportunities for new actors in the national energy market, and the push for technological development such as the use of batteries for energy storage," said Gomez.
"Partnerships like this help to achieve Chile's renewable power targets. Securing a 24/7, long term, 100% renewable PPA highlights how important green power is to our customers and is testament to our sustainability commitment," said Axel Thiemann, Sonnedix chief executive.
Glencore and Anglo American both hold 44% of Collahuasi, with Mitsui & Co controlling the remaning 12%.