MINE POWER
Sustainable solutions
With hybrid renewable systems now embedded at remote mine sites , what is next for the mine power sector ? Dan Gleeson finds out
It is no longer acceptable to find any available
energy solution to get new remote mines up and running ; that solution needs to be cost effective , sustainable and ‘ green ’.
Any mine or exploration site using diesel-powered generators is actively looking for a more environmentally friendly alternative , while the major miners are investing significant amounts in
renewable projects to move their sites off fossil fuelbacked energy sources to more sustainable inputs .
These energy sourcing requirements are affecting mines both big and small , as Malavika Jain Bambawale , Managing Director , Sustainability Solutions ( APAC ) at ENGIE Impact , the consulting arm of electric utility company ENGIE , made clear .
“ There is an increasing interest and sense of urgency for sustainability within the mining industry , driven by investor activism , as seen with recent announcements made by Australia and New Zealand Banking Group and Tesla ,” Bambawale told IM . “ Miners need to go beyond low-hanging fruits to answer to the above-mentioned pressures , in addition to looking into their energy mix to avoid limited decarbonisation .”
Just some of the solutions they are examining include renewable generation mixed with battery systems and a smaller diesel-powered element , partially displacing diesel use with LNG , fully renewable power projects and – more recently – the use of ‘ green ’ hydrogen .
Net zero
Many of these solutions are factored into an increasing number of mining company mission statements to get to ‘ net zero ’ by a certain date in the future .
Miners are going down different avenues to achieve these executive-led sustainability targets , according to Bambawale .
“ There are many ways to achieve a decarbonised end goal and the roadmap an organisation chooses to get there can have a major impact on factors such as cost , risk and feasibility ,” she said .
ENGIE Impact ’ s understanding of decarbonisation technologies , combined with internally developed software modelling tools , has been leveraged by miners such as Vale New Caledonia to find the optimal pathway . The company sets out advanced roadmaps to hit goals and creates a “ tangible action plan ” to ensure a phased implementation occurs .
Some common topics coming up during ENGIE Impact ’ s interactions with miners include ‘ green ’ electricity supply and decarbonising vehicle fleets . Depending on the type of operation , process-related emissions ( due to chemical reactions ) might also be a consideration .
The latter consideration is typically the most difficult to deal with as it may require a process rethink , according to Bambawale .
“ So , for this category of emissions , we see an interest to deploy offsets in the short or mid-term , while the decarbonisation efforts are focused on the electricity and fuel supply ,” she explained . “ However , to address the process-related emissions in the long term , there is a need for a holistic rethinking and codevelopment of solutions to better match energy consumption with renewable energy production .”
For all the ESG benefits that come with employing these solutions , miners and their shareholders still want a significant return on investment from these projects .
“ The main thing to consider for any solution is that competitiveness is key within the mining sector ,” Bambawale said . “ The costs need to be recouped either through savings or through increased market differentiation and pricing for ‘ green ’ minerals .
“ However , some miners are also keen to be early
There are more than 20,000 solar panels producing 8 MW of power at Gold Fields ’ Granny Smith mine ( photo : Aggreko )
adopters of new technologies with a greater risk appetite to testbed new , yet-to-be-proven technologies .”
Obvious examples here are Anglo American with its 291 t FCEV haul truck project at the Mogalakwena PGM mine in South Africa , which will use ‘ green ’ hydrogen as a fuel source ; Nouveau Monde Graphite ’ s all-electric open-pit mine plan at Matawinie , in Quebec , Canada ; and what was initially Goldcorp ’ s ( now Newmont ) all-electric underground gold mine concept at Borden , in Ontario , Canada .
Rise of the hybrids
There have been enough hybrid power applications coming online in the mining space to prove the concept .
Tarik Sfendla , Market Development Manager , Africa , Wärtsilä Energy , says a hybrid setup is the most effective way to deliver reliable clean power to remote off-grid mining operations in Africa , and Wartsila has several case studies on the continent to back his opinion up .
In Mali , it is helping deliver a hybrid power solution combining solar , battery and thermal generation technologies for Resolute Mining ’ s Syama gold mine . As part of an agreement with Aggreko – a company also working on this project – it will deliver four Wärtsilä Modular Block enclosures , with one medium-speed Wärtsilä 32 engine in each , to provide 40 MW of energy to Syama .
It is also in the process of designing and engineering a 17 MW / 15 MWh energy storage system based on the company ’ s GEMS hybrid energy management solution for B2Gold ’ s Fekola mine in Mali . This system will control a new 30 MW solar plant to be integrated with a heavy fuel oil component .
Wartsila also previously delivered a 15 MWp solar photovoltaic ( PV ) power plant to the independent power producer Essakane Solar SAS , which supplies the Essakane gold mine , in Burkina Faso ( majority owned by IAMGOLD ). The solar PV plant was constructed next to a 55 MW power plant running on heavy fuel oil , with the engine power plant providing backup , while the solar farm produces energy during the day .
Aggreko also a solid track record when it comes to integrating renewables within a hybrid power plant solution at mine sites .
It recently completed a project at the Granny Smith gold mine in Western Australia , which includes one of the world ’ s largest renewable energy microgrids . The new hybrid power system , which has been integrated with Aggreko ’ s existing gas-fired power station , is powered by more than 20,000 solar panels producing 8 MW of power and supported by
26 International Mining | JANUARY 2021