Following the commissioning of the world’s largest off-grid solar-battery hybrid system for the mining industry, at the Fekola gold mine, in Mali, expectations to reduce the mine’s heavy fuel oil consumption by over 13-million litres a year and to lower carbon dioxide emissions by an estimated 39 000 t/y have already been exceeded, Suntrace business development and sales manager Ralf Jungebloed tells Mining Weekly.

“Solar production, to date, indicates that the plant will exceed initial power production estimates,” he adds.

German renewable energy company Suntrace, together with Canada-based gold mining company B2Gold, in April completed commissioning of the hybrid system.

The solar-battery hybrid plant was integrated and commissioned successfully with the existing power plant operation.  

Hybrid projects such as this, which combine solar energy with conventional energy generation and battery storage, are an effective way to provide reliable power supply day and night in off-grid areas.

As it was ideally suited to B2Gold’s needs, the company approved the $38-million hybrid project for implementation in July 2019, following completion of preliminary studies by Suntrace and BayWa.

The Fekola gold mine operates 24 hours a day.

During the daytime, the 30 MW solar plant allows three out of six heavy fuel oil generators to be shut down; the energy production of the residual three generators could also be significantly reduced.

The 15.4 MWh battery storage compensates energy generation fluctuations and assures a reliable operation, which allows up to 75% of the electricity demand of the gold mine to be covered by renewable energy during the daytime.

Jungebloed indicates that the metals used in the system are a lithium iron phosphate battery.

He says hybrid solutions with renewable energy sourced power operations are a realistic and effective means for increasing energy reliability and lowering operating costs for the mining sector.

Moreover, he notes, it also helps the mine achieve its environmental and cost saving goals.

“The evaluation of different options is essential for a mine, because every situation is individual and needs a tailor-made solution.

“The management of the mine should focus on their core business and partner with an independent adviser to evaluate the techno-economic solution and to find the right partners for construction and commissioning,” Jungebloed advises.