Pod 2: Decarbonising power with renewables and storage

Stantec’s Trevor Gilchrist chairs a panel discussion with Tsakani Mthombeni, Executive, Sustainable Development, Impala Platinum; Pierre Gueudet, Energy & Climate Director, Eramet and Francois Swanepoel, Technical Manager, Salares Norte, Gold Fields on strategies for decarbonising power.

In the second content pod, speakers looked at renewables and storage as specific decarbonisation avenues. In a panel on strategies for decarbonising power, chaired by Trevor Gilchrist, Practice Leader, Mining, at Stantec, participants discussed whether renewables are the new normal for powering mines. Representatives of Gold Fields and Eramet confirmed that it is now systematic for their companies to consider renewable power options for new projects, which often prove more cost-effective than fossil fuels in the long run.

The industry in general is very optimistic about the possibility to completely decarbonise power supply in the medium term, thanks to emerging technologies. “It is now possible to go from complete reliance on diesel to 128 days without even switching on the diesel generator,” hailed Mark Kennedy, Business Development Manager at Wärtsilä, referring to the Graciosa Island in the Azores. According to him, energy storage is the technology that has made much of this progress possible, and switching to hydrogen is set to make year-round 100% renewables possible. The company is now working to get 100% hydrogen power plants to market by 2025.

Martin Schlecht, Chief Operating Officer, Suntrace, presents the options for high penetration renewables for mines

Another company eyeing carbon-free power supply for mines is 247 Solar, which provides a 20-hour thermal battery charged by concentrated solar power. “You can get to zero-carbon all-electric mining, not today, but sometime in the future, on your timeline,” said Bruce Anderson, the company’s President and Founder. The HeatStorE Battery is the first battery that can operate at full power even when fully discharged, because it includes a turbine. “It can burn diesel for now, but green hydrogen too when it’s available,” added Anderson.

In the hybrid power and storage space, technical advances go hand in hand with commercial innovation, which is needed to handle what are generally high-capex projects. “Minimizing capex while still being able to maximize production to meet growing market demands, and at the same time progressing towards meeting aggressive energy transition goals is a challenge,” said Nick Dunn, North America Mining Sector Manager at Aggreko. For this reason, the company offers a turnkey service that requires no capex, yet guarantees reliability and equipment flexibility.

“It is now possible to go from complete reliance on diesel to 128 days without even switching on the diesel generator”

MARK KENNEDY BUSINESS DEVELOPMENT MANAGER WÄRTSILÄ

Slide from presentation by Mark Kennedy, Business Development Manager, Wartsila

Storage remains challenging when it comes to cost, particularly when thinking of using batteries to increase renewable penetration. Martin Schlecht, Chief Operating Officer at Suntrace, noted: “Now 20% fuel saving through renewables is a proven case, with a battery to add grid stability through primary frequency control. Getting to a 50% renewable share is possible if you expand to a four-hour battery, but already, it is not as economic.” Schlecht suggested a staged implementation to maintain flexibility as technology costs continue to decrease: according to BloombergNEF, lithium-ion batteries have a learning rate of 18%, meaning that their price drops by this percentage every time there is a doubling of supply capacity.

Bunty Kiremire, Application Lead at Release Scatec, confirmed that commercial innovation is needed for higher-penetration remote hybrids. “Technical aspects are largely solved and the business case is strong, but it’s the commercial aspects that seem to be holding up mines from integrating hybrids, either large CAPEX or long-drawn-out third party agreements that are so complex they take years to be established and eventually don’t happen at all.” Scatec’s Release, a re-deployable, modular and scalable PV and battery solution, is a response to this need for innovation: “We take the full technology risk and the customer has the option to extend or terminate the lease.”

This level of technical and commercial innovation bodes well for power decarbonisation to push miners closer to their 2030 and 2050 targets. “Mining is known to be slow to respond to disruptive technologies but in this case we have been one of the leaders in taking advantage of these technologies to augment our electricity supply while reducing our carbon footprint,” noted Tsakani Mthombeni, Executive, Sustainable Development, at Impala Platinum.

“Minimizing capex while still being able to maximize production to meet growing market demands, and at the same time progressing towards meeting aggressive energy transition goals is a challenge”

NICK DUNN NORTH AMERICA MINING SECTOR MANAGER AGGREKO

Slide from presentation by Bruce Anderson, President and Founder, 247Solar