"We expect the next upcoming milestone to be the commissioning of the water supply and testing the now fully installed mill," Hummingbird CEO Dan Betts said.

The company continued to evaluate renewable power options such as solar PV to supplement the modular generator configuration which was "the most efficient in their class".

"Aggreko offers the best quality power solution in the market at competitive pricing with a full team on site to run and maintain its operations," Betts said.

The portable power supplier has a seven-year contract at Yanfolila. Aggreko managing director, Africa, James Shepherd said reliable, cost-effective power was critical to remote mines.

"Aggreko's technologies provide a scalable and efficient power that can accommodate any change of needs and resources available," he said.