Aggreko has helped Kinross Gold shore up its power supply at the Tasiast gold mine in Mauritania, providing a turnkey heavy fuel oil (HFO) solution that has given the company time to review its longer-term energy needs.

The Tasiast mine is one of the largest open-pit gold mines in Africa, located in the remote north western region of Inchiri in Mauritiana.

As an off-grid mine it needed to have its own power supply and was being powered by a 25 MW HFO Wartsila power plant, with an additional 10 MW of diesel, both of which Kinross own, Aggreko said.

“The diesel technology was ageing, very inefficient and prone to regular breakdowns, which was incurring Kinross huge maintenance costs,” Aggreko explained.

Furthermore, the company had recently completed phase one of an expansion of the mine. This included the installation of a new SAG mill to increase the rock crushing capacity by 50% – from 8,000 t/d to 12,000 t/d – however, the power generation capacity had not been upgraded. This meant the redundancy available on site was significantly decreased once the mine expanded and heightened the risk of power failures.

The life of mine was expected to be at least another decade away in 2029 too, and, with the diesel price volatility impacting operations, Kinross needed to think about power for the mine over the longer term, as well as what it could do to alleviate the cost implications it was suffering, short term, Aggreko said.

It engaged Aggreko to explore the options.

To address the immediate issues, Aggreko offered a solution that was easy to integrate into the team’s current power mix, it said.

“Replacing the existing diesel plant with 13 MW of Aggreko’s HFO power meant we could reduce their reliance on diesel, and they could keep the old diesel sets as additional redundancy for emergencies,” the company said.

“We synchronised with their existing Wartsila HFO plant and integrated the systems smoothly with no interruptions to their operations – ultimately safeguarding production.”

With Aggreko providing a turnkey solution, the company didn’t need to worry about operating or maintaining this new plant, it said.

Delivering the plant on time was also crucial for Kinross, Aggreko said.

With eight months of planning, the contract was signed in June 2019. This requested Aggreko to deliver and commission the plant by the last day in November of the same year.

“Putting our deep experience of operating in Africa to use, specifically our knowledge of local importation and logistics challenges, we delivered the project not only on time, but also on budget,” Aggreko said.

Aggreko concluded: “Kinross have reliable, guaranteed power 24/7 to ensure their gold production is unaffected by power issues or further shutdowns, and it’s given them the breathing space and time to review longer-term power options for the remaining life of the mine.

“The solution we put in place to use HFO also made the fuel management easier using one fuel across both their existing Wartsila plant and the new plant, which was also more cost effective.”

Tasiast produced 391,097 ounces of gold equivalent in 2019, according to Kinross. For the second consecutive quarter, the mine achieved record quarterly production and a record average throughput rate of 16,100 t/d in the March quarter, as the mine continued to benefit from the phase one expansion.

The company is also in the middle of a phase stage expansion at the operation, which could see throughput capacity increase to 24,000 t/d by mid-2023.