MATERIALS AUSTRALIA
WA Branch Annual Sir Frank Ledger Breakfast The Challenges of Achieving Zero Emissions in Remote Mining Operations Source: James Koerting, Energy Manager, Gold Fields Australia
(L to R): Mike Ledger(Sir Frank Ledger’s grandson), Schree Chandran, James Koerting.
James Koerting (Energy Manager, Gold Fields Australia) delivered the keynote address at the 2021 Sir Frank Ledger Breakfast on the topic: The challenges of achieving zero emissions in remote mining operations. Koerting has been one of the leaders in the switch to renewable energy supply for Gold Fields Australia’s local operations. Incidentally, he also revealed that he has a family link to Sir Frank Ledger, whose achievements and founding role in what was to become Materials Australia are honoured each year at this annual breakfast meeting. Gold Fields Australia has been on a strategic journey to convert the primary energy sources for its remote mining operations in Western Australia, establishing renewable energy microgrids at the Agnew, Granny Smith and Gruyere mines. Gold Fields has successively introduced solar, battery, wind and gas hybrid energy systems to augment traditional gas and diesel 10 | APRIL 2022
power units. Its flagship installation at Agnew has led to 54% energy supply from renewable sources and a net 42% reduction in total mine emissions. Gold Fields is not alone in the move to renewables in mining. Reflecting the international pressure for investment that takes into account Environmental, Social and Governance (ESG) issues, the major mining houses are aiming for a 30% to 40% reduction in greenhouse gas emission by 2030 and net zero, or carbon neutral, operation by 2050. The path to zero emission is based on elimination, and where this is not possible, neutralisation. However, as Koerting noted, if it were easy, it would have been done by now. The factors in the arguments against the change include ‘short mine life’, ‘high risk’, ‘too much capital’, ‘short battery life’, and more. Nevertheless, Gold Fields’ achievements at Agnew show what can be done under the right circumstances. BACK TO CONTENTS
Koerting pointed out that as the mines mature, they become more energy intensive. This is because they become deeper, haul distances increase, and grades usually decline. As such, the longer the mine life, the greater the challenge for net zero operation. However, on the other hand, the greater to opportunity to make longer-term investments to achieve net zero. The path towards zero emission involves two steps: convert electric energy sources to renewables, and convert diesel fuelled mobile equipment to electric power. The developments at Gold Fields’ operations have been directed at renewable energy but anticipate increased electricity demand as the conversion from diesel proceeds. The renewable component of the Agnew operation has 16 MW of wind power (five turbines) and 4 MW of solar-tracking photovoltaics (PV), supplemented by a 4 MWh lithium-ion battery (which can deliver 13 MW). However, the mine still WWW.MATERIALSAUSTRALIA.COM.AU
