Australia: groundbreaking solar array for offgrid mine commences operation

In what is hoped to be a crucial demonstration process for the mining industry, a ground mounted solar array has begun feeding electricity into a mini-grid at a remote mine site. The 1.7 MW Weipa array will supply a bauxite mine operated by global mining giant Rio Tinto, displacing around 600,000 liters of diesel fuel annually.

The solar array was developed by First Solar and employs 18,000 modules in combination with First Solar’s FuelSmart micro-grid integration technology. The PV system is expected to generate 2800 MWh of electricity annually, which is up to 20% of the remote townships electricity needs. Weipa is located on the Western Cape York Peninsula, in the far northeast of Australia.

The electricity generated by the Weipa offgrid solar array will be purchased by Rio Tinto under a 20 year PPA.

“This power purchase arrangement is an opportunity to trial the introduction of an alternative power source such as a solar plant into a remote electrical network like the one here in Weipa,” said Rio Tinto Weipa Operations general manager Gareth Manderson.

“It is already widely acknowledged that solar electricity is typically cheaper than diesel-powered electricity, particularly in remote locations,” added Jack Curtis, First Solar’s Regional Manager for Asia Pacific. “The significance of the Weipa Solar Plant is that it provides the opportunity to demonstrate that PV-diesel hybrid projects can also be as reliable as stand-alone diesel-powered generation.”

While the economics of a solar array stack up very favorably when compared to trucked diesel at remote locations such as Weipa, there are a number of challenges in realizing such projects including the short lifetime, at least on paper, of many mining operations. The PPA under which Weipa has been developed is a potential solution to this problem. Mining operators also tend to be relatively risk averse, pointing to the importance of the Weipa project as a proof-of-concept.

“At the Weipa Solar Plant, First Solar is seeking to deliver a reliable electricity supply without diverting capital costs away from Rio Tinto’s critical mine operations. Proving this commercial model has the potential to be a watershed moment for the diesel hybrid application globally,” said Mr Curtis.

First Solar’s Curtis indicated also that reliable electricity supply through the solar-diesel hybrid is another challenge to offgrid solar mining projects.

The Weipa project has been supported by an AU$3.5 million grant made available by the Australian Renewable Energy Agency (ARENA). ARENA has indicated that it is willing provide up to AU$7.8 million for the second phase of the Weipa project that could include extending the solar array to 6.7 MW, and integrating electricity storage. The expanded project could save some 2.3 million liters of diesel annually.

“This is the first time a remote Australian mining operation has been supplied with power from solar PV on such a scale. The success of phase one is set to create a precedent for industry by demonstrating that solar PV is a viable option for powering off-grid locations, like mine sites, in Australia,” said ARENA CEO Ivor Frischknecht.

The All Energy Australia trade show kicks off next week in Melbourne, bringing together solar professionals from around the country and region.