Assessing Rio Tinto’s Renewable Resources in the Pilbara

Much like other Tier 1 miners, Rio Tinto has committed its business to a goal of net zero emissions by 2050 — along with targets for a 15% reduction in absolute emissions and a 30% emissions intensity reduction. In 2019, the company struck a deal with its biggest Chinese iron ore customer, China Baowu Steel Group, to find ways to reduce the carbon emissions associated with the steelmaking process. This was one of the first direct actions by a miner to try to reduce its scope 3 emissions.

In February 2020, Rio Tinto announced its first large-scale foray into renewable energy, having approved a US$98mn investment in the Pilbara (Western Australia) to build a 34 MW solar plant at its Koodaideri mine and a 12MWh battery located in Tom Price to improve spinning reserve on the network “That’s our first moderate step in our pathway,” says Kieran Birch, Study Lead at Rio Tinto, adding that the tendering process for these two projects will begin early in 2020.

Birch has been working in the company’s environmental operations since 2008, but today, his job in Studies and Technology is to examine applications for renewable and alternative energies in the Pilbara. “We’ve set targets towards net zero emissions in the Pilbara, so the team and I are looking at the emissions reduction pathways to get us there,” he says.

In the region, Rio Tinto’s operations are running on gas power, which is already lower in emissions than diesel. But the company wants to drive value through low-cost, low-emissions technologies, and the Pilbara is blessed with an abundance of solar and wind resources. “We have a world-class solar resource in the Pilbara, and an opportunity to leverage the power network we own and operate there by integrating renewables into it to start displacing that gas,” Birch explains.

Around the world, Rio Tinto is lucky to have access to a lot of hydropower, which means that 76% of the energy it uses is already sourced from renewable sources. Still, at the scale of a global miner, 24% non-renewable energy means significant amounts of gas and diesel. The company is not unfamiliar with wind and solar integration: in 2012, under a build, own, operate model it installed a wind and diesel hybrid plant at the Diavik diamond mine in Canada, and in 2015 through an IPP it introduced a solar hybrid installation at the Weipa bauxite mine in Queensland, Australia. Rio Tinto has been able to learn from the management and engineering challenges from these projects to support its newly announced projects in WA.

For its second owned and operated renewable project, the company is in a fortunate position in the Pilbara: on top of the abundant solar resource, Rio Tinto already has a robust interconnected grid between all of its mines in the area, allowing it to inject renewables at a risk-savvy pace. “It’s important that we maintain the power network to provide for 24-hour production and support the great teams we have to do so,” says Birch. “The risks are around technical integration management, as maintaining security of supply and network stability and reliability are absolutely paramount to the business.”

Understanding the patterns

Key to any effort to integrate renewables into an existing power supply is to understand the patterns of solar and wind resources. Rio Tinto thoroughly assessed its access to solar energy before announcing the Koodaideri solar farm, and plans to use predictive technologies in order to respond quickly, should clouds approach. Birch explains that supporting technology like batteries will also allow the company to increase the amount of solar into the network. “And we will be working with our utilities team, who are effectively our end users, to ensure that they have the knowledge and the skills to manage the assets once they come online. It’s about understanding what’s required to manage those technologies, understanding the risks and working with all the key stakeholders,” he adds.

Now, Rio Tinto is starting to assess its wind resources in the Pilbara, too. Working with Fulcrum 3D, it has installed a number of SODAR (sonic detection and ranging) instruments, used for wind profiling, at its sites. “We’re at the beginning of the journey, assessing the wind resources available to determine where the investments might be best suited in the Pilbara for renewable wind energy. We are continually assessing the data and progressing studies based on the results of that data,” notes Birch.

Finding the business case

As opposed to the East Coast, where displacing expensive gas or diesel with cheap renewables is a no-brainer, the business case in WA is not as competitive, due to widely available and lower cost gas resources. For that reason, miners in the region must be smart when integrating clean energy into their power mix: adding these resources at a reasonable pace and optimizing their use to the maximum.

“The Pilbara and more broadly WA is very fortunate in having lower-cost gas, so the business case for renewables is more difficult, despite the world-class renewable resource there. The reason for integrating renewables there is not solely financial though we are encouraged by the financially positive business case approved. Rio Tinto produces materials that play a key part in the transition to a low-carbon economy. We want to be part of driving the momentum for solutions, so the first step is understanding the simple, no-regrets solutions that we can employ now and that will assist our knowledge and comfort with these sorts of projects in the future,” notes Birch.

“Companies are focusing more and more on their sustainability strategy and will always tackle these sorts of projects in a measured and well considered way,” Birch explains. “It’s critical if we are to succeed in getting to Net Zero Emissions by 2050 we start the journey now to understand how to integrate and work with these technologies. There’s a learning curve that needs to take place.”

In the near future, Rio Tinto will start tendering its solar and battery project in the Pilbara, continue to collect data on the wind resources in the region, and progress activities to achieve their reduction targets. “More of the same, with an exciting pathway to do a lot more in emissions reduction,” concludes Birch.

Renewable resource monitoring with Fulcrum3D

Fulcrum3D provides wind and solar resource measuring devices and data capture for resource management. The company has seen the mining sector’s interest in these technologies grow exponentially in the past few years — in fact, the mining segment was a primary avenue of growth for Fulcrum3D in the last 18 months. In the past year, the company has deployed monitoring stations to over 10 mining sites in Western Australia (WA) alone, and expect growth to accelerate further in 2020.

“In the past decade we’ve performed monitoring campaigns for mining companies and ultimately witnessed these stall, so it’s excellent to see what’s going on right now with renewables in mining and the projects being followed through,” says Paul Copestake, Head of International Markets. “I personally love working closely with these guys from pre-deployment to gathering the data and seeing the projects move forward.”

Fulcrum3D is currently working with Rio Tinto in WA, assessing wind resources available to the miner’s operations in the Pilbara. Fulcrum3D SODARs (sonic detection and ranging) have been deployed to record wind speed and direction data up to 150m at multiple locations. “Our SODAR is quick and easy to deploy with most installations taking little over an hour — having installed it a few hundred times, any niggling difficulties have been ironed out! With inbuilt power and comms kits the trailer-mounted design is easily moved around in order to gain a more detailed understanding of the wind regime across the site,” explains Copestake, adding that Fulcrum3D is supporting Rio Tinto and their consultants in understanding the wind data being recorded.

Energy and Mines: What are some of the differences you find in working with mining clients as opposed to IPPs on renewables resource monitoring?

Paul Copestake: We also work with the leading wind and solar farm developers in Australia and overseas and whether it’s these guys or mining companies, we love the variety of projects and different demands of those. Ultimately whilst we might be a bit more hands-on with our mining clients, everyone wants good data to analyze and progress their projects, and that’s what we’re in the game of providing.

E&M: How does Fulcrum3D differ from other types of renewables resource monitoring services?

PC: Whilst Fulcrum3D has and continues to experience exciting company growth, we maintain a tight-knit team of engineers, physicists and technicians, who genuinely take an interest in our client’s needs. We retain a strong focus on R&D, demonstrated through our work in wind and solar forecasting for operational renewable energy projects –- the Fulcrum3D SODAR is being trialed at operational wind farms in order to provide short term power forecasts.

Our monitoring stations are widely used for resource monitoring during project development and also performance monitoring throughout plant operation. This, coupled with our internal expertise and in-depth knowledge of the instrumentation and applicable standards allows us to provide great advice on monitoring practices and explain why these become important during the operation of renewable projects. Another key difference is the robustness of our hardware, software and communications in some of the world’s harshest environments. Our stuff just works and our unique capabilities around data insight allow our clients to understand the resource and how that resource will interact with their proposed (or existing) power plant.

E&M: What are some of the key considerations for mines when trying to identify the right combination of renewable energy technologies for a site?

PC: Understanding the resources available by carrying out on the ground measurements are critical to first-rate project development. Properly understanding your renewable resource will allow you to better model future project operation and in turn understand how the combination of power sources can best work together.