Mining company Gold Fields and energy producer EDL have completed the first stage of a renewable energy project that will eventually see wind and solar deliver half the power needs of the Agnew gold mine.
Mining company Gold Fields and energy producer EDL have completed the first stage of a renewable energy project that will eventually see wind and solar deliver half the power needs of the Agnew gold mine.
A 4-megawatt solar farm at the mine was officially opened this week, while erection of the first of five wind turbines is due to start later this month.
The solar farm is backed up by a 16MW gas-fired power station and a 3MW diesel plant.
The second stage of the project, due to be completed in mid-2020, comprises an 18MW wind farm, a 13MW battery and a control system to ensure all the components of the microgrid operate efficiently.
Once completed, the Agnew project will be the first to use wind generation as part of a large hybrid microgrid in the Australian mining sector.
It will be followed by GMA Garnet Group, which is developing a similar but much smaller hybrid renewables project at its Port Gregory mine.
Speaking at the official opening of the Agnew project, Gold Fields Executive Vice President Australasia Stuart Mathews said it improved energy security while reducing energy costs and the project’s carbon footprint.
“We are hopeful that this will enable other companies to consider these options for decarbonising their operations,” he said.
The Agnew mine, which has operated for 38 years, historically sourced its power from BHP Nickel West’s nearby operation at Leinster.
Gold Fields developed its own power sources so it could obtain more than 12MW, which was the previous limit.
Mr Mathews said Gold Fields was investing up to $25 million a year in exploration at Agnew to ensure the mine had a long-term future.
“It’s looking very positive,” he said.
EDL is developing the $112 million power project and will operate it under contract for 10 years, at which point ownership will revert to Gold Fields.
Mr Mathews said the mine’s power costs would fall by about half from that point.
A big part of the development cost rests with the five wind turbines, which have been partially-funded (to the tune of $13.5 million) by the Australian Renewable Energy Agency.
Once they are up and running, the wind farm is expected to have very low operating costs.
The Agnew project will have total installed capacity of 54MW, about three times the maximum load at the mine.
The ‘excess’ capacity means EDL will be able to switch between different power sources, depending on wind levels, cloud cover and other conditions.
The battery will allow the mine to continue operating for about 10 minutes when the gas plant needs to be fired up.
Mr Mathews said renewables will supply up to 54 per cent of the mine’s power needs over time.
EDL chief executive James Harman said the project was leading the way towards clean, renewable energy to power remote, off-grid mining operations without compromising reliability or power quality.
Energy minister Bill Johnston congratulated EDL and Gold Fields for their collaborative work.
“This innovative, Australia-first project is setting the standard for mine sites throughout Western Australia,” he said.
Agnew is one of four gold mines operated by Gold Fields in WA.
At its Granny Smith mine, it has contracted Aggreko to build an 8MW solar farm and a 2MW battery.
They will be integrated with Aggreko’s existing 24MW gas power plant.
This combination is projected to reduce fuel consumption by between 10 and 13 per cent.
At Gold Fields’ newly-built Gruyere gold mine, APA Group has built a 198-km gas pipeline and 45MW gas-fired power station.
NB: The journalist travelled to Agnew as a guest of EDL.
