The majority of mines in Africa are mostly located in areas with a high solar resource, but many off-grid mining operations are burning diesel to power their operations, incurring high fuel and environmental costs, solar energy solutions company SolarReserve CEO Kevin Smith states in a ‘Renewables and Mining’ report, released by renewable energy and mining organisation Energy and Mines last month.

He says in the report that, with a significant number of off-grid applications in the mining sector, replacing diesel with solar power solutions can offer significant savings for remote mining operations.

“SolarReserve has commercialised concen-trated solar power (CSP) technology that is used in conjunction with integrated energy storage,” he notes, adding that the company’s CSP technology uses molten salt in a tower configuration, which is a field of mirrors that are used to focus the sun’s energy onto a heat exchanger on top of a central tower.

“We use molten salt as the working fluid to capture and store the sun’s thermal energy until energy is needed,” he says.

24-Hour-a-Day Solution

Smith also mentions in the report that most mines have operations 24 hours a day, and installing solar photovoltaic (PV) technology can assist with the daytime generation load, noting that SolarReserve’s CSP technology provides a 24-hour-a-day solution.

He explains that the company’s first large-scale project, the Crescent Dunes solar energy project, in Nevada, US, is a 110 MW facility that is nearing completion and will provide electricity for Nevada’s electricity grid.

Smith notes that some misconceptions about the mining sector and CSP storage are that electricity can be generated from solar energy only during the day and that solar can only handle part of the generation load.

“The fact that there is a viable energy storage solution changes the game because energy storage enables mining operations to have solar power on demand.”

Another misconception is that solar applications are expensive; however, the costs of these applications has substantially decreased over the last five years.

Smith further states that if a mine is burning diesel, it can achieve a 50% savings in energy costs using solar energy instead.

“CSP storage has the potential to replace diesel backups. “We are considering hybrid structures, where we use PV to handle the day-time energy load and CSP to provide overnight capacity, with a small amount of diesel backup.”

Smith adds that, rather than running a mining operation substantially on diesel, it could eventually run 1% or 2% of the year for an off-grid application.