Owner/operator: AGL Energy/Malakoff Corporation Berhad

Fully commissioned in January 2013, the 420-MW Macarthur Wind Farm is the largest wind farm in the Southern Hemisphere. But sourcing and erecting 140 wind turbines for this massive project was logistically challenging and required a rethink on several levels. 

Though endowed with some of the world’s largest coal resources, Australia—whose southern coasts experience strong westerly winds called the “Roaring Forties”—also has wind power as a natural choice. For centuries, these powerful, largely unhampered west-to-east air currents, which are caused by a combination of air being displaced from the Equator towards the South Pole and the Earth’s rotation, helped speed ships sailing from Europe to Australasia. Today, they furnish hundreds of sites in South Australia with wind speeds averaging 8 or even 9 meters per second (m/s) at 50 meters (m) above the ground—giving the nation wind power resources that excel by world standards.

Yet the country’s wind power sector is just getting started. At the end of 2012, wind turbines with a total nameplate capacity of 2,548 MW supplied more than 7,700 GWh, or 3.4%, of Australia’s overall electricity demand. Wind’s outlook is healthy: The current renewable energy target (RET) set by the Australian government requires 20%—or more than 45,000 GWh—of the country’s total power generated to be sourced from renewables by 2020, and at least 19 GW of new wind projects are in the pipeline.

Industry analysts forecast the growth of wind power will be sustained despite the conservative Liberal Party’s sweep to power in the Sept. 7 election, which ended a six-year term led by the largely wind-supportive Labor government. Newly elected Prime Minister Tony Abbott has pledged to repeal the year-old national carbon tax of A$23 per metric ton of carbon dioxide equivalent emissions that was expected to last until July 2015, after which the country was to transition to an emissions trading scheme. But he has also pledged to shutter the publicly funded A$10 billion Clean Energy Finance Corp. (CEFC), and press on with a biennial review of the RET policy, begun in January 2010 and next due for review in 2014.

Thinking Big

In this context, full completion last January of the 420-MW Macarthur Wind Farm in the southeastern state of Victoria, Australia’s most noteworthy wind installation to date, marked a tremendous milestone for the country’s fledgling sector.

More than 350 people were directly employed during the 30-month construction of this A$1 billion project’s 140 wind turbines near Hamilton, about 245 kilometers (km) west of Melbourne—making it the largest investment in Australian renewable energy since the 1974-completed Snowy Mountains Scheme, a hydroelectric project widely considered an engineering wonder.

Development of the Macarthur Wind Farm was initiated in 2007 by AGL Energy Ltd. (AGL) and its former 50:50 joint venture partner Meridian Energy, which is based in New Zealand. The project is now owned by AGL and Malakoff Corporation Berhad. Though primarily built by a consortium comprising Australian infrastructure and mining firm Leighton Contractors and Danish wind turbine maker Vestas, a number of local suppliers also participated. Keppel Prince Engineering, from Portland, Victoria, for example, manufactured 80 of the 140 wind towers. The remaining 60 towers were supplied by Adelaide-based RPG Australia.

But the project also necessitated an array of other local resources, including materials from nearby quarries and trucking companies, which supplied crushed rock and other materials for the 85 kilometers of internal roads and other materials for the significant public road upgrades that were undertaken by project developers to ease transportation of a plethora of parts—including blades, nacelles, and hubs—imported to the Port of Portland from Denmark.

Siting and Procuring Permits

The Macarthur Wind Farm’s 140 turbines are spread out across 5,500 hectares on three near-flat farms owned by separate landowners—a site chosen specifically because it has “a productive wind regime” and average wind speeds of about 7.6 m/s, says AGL. Those are speeds that the U.S. National Renewable Energy Laboratory would rank as class 5 or higher, with class 3 or greater designated as suitable for most utility-scale wind turbine applications. AGL estimates the project’s capacity factor—the amount of power produced per year divided by the amount of power that would be produced if the wind turbines operated at full capacity all the time—is 35%.

However, the site also offers proximity to a 500-kV transmission line for connection to the state grid, and it has good road access to the Port of Portland, from which most of its imported heavy equipment was trucked in, and where many of the wind turbine tower sections were manufactured. Developers then procured all necessary permits, including a state planning permit that set strict noise limits. Enforced by the Victoria State government, the permit requires noise monitoring to be carried out at specific neighboring buildings and that the noise level from an operating wind farm at any relevant nominated wind speed cannot exceed the background noise before the wind farm was built by more than 5 decibels (dBA), or a level of 40 dBA, whichever is greater. AGL has undertaken over 40,000 hours of noise monitoring, and according to the company, noise loggers installed between February and March 2013 for an objective assessment confirm the wind farm remains compliant with these strict limits.

Newly Launched Technology

Yet another remarkable consideration that qualifies this project as a POWER Top Plant is that the Macarthur Wind Farm uses the world’s first purchased Vestas V112-3.0 MW wind turbine model (Figure 1). The deal between the wind turbine manufacturer and project developers for 140 of the newly launched turbines was cemented in August 2010, and it comprises a full engineering, procurement, and construction contract; a 10-year service agreement; and a VestasOnline Business supervisory control and data acquisition solution.

1. The first buy. The V112-3.0 MW wind turbines installed at the Macarthur Wind Farm were Danish wind turbine maker Vestas’ first sale of that turbine model (though not the first installed in the world). About 1,120 heavy lifts were required to join the tower sections, nacelles, hubs, and blades of the farm’s 140 turbines, each of which has a hub height of 85 meters (m) above ground and a rotor diameter of 112 m. The wind farm, in a region with average wind speeds of 7.6 m/s, has a capacity factor of 35%. Courtesy: AGL Energy

For AGL, the choice to use Vestas’ new V112-3.0 MW was based on economics. It allowed the company to increase the wind farm’s capacity while reducing the number of towers from 174 to 140, said AGL CEO and Managing Director Michael Fraser. “This reduces the environmental footprint of the project and achieves substantial operating cost savings in excess of [A]$30 million over the [25-year] life of the wind farm.” Former co-developer Meridian Energy revealed that it did “extensive due diligence” through site visits and technical meetings to ensure the V112-3.0 MW platform was “the right solution for the project.”

Clearing Hurdles

Finally, though it was “logistically complex,” Vestas and Leighton Contractors delivered the wind farm three months ahead of schedule (see table).

As Vestas Construction Supervisor Gary Barret recalled, “We would jump over one hurdle and were confronted with another the day after.” For one, the V112-3.0 MW turbine is the biggest wind turbine ever to be installed in Australia, and that brought about its own challenges—and eventually even changed the rules on inland oversized transport.

“Transporting the longest blades and the heaviest nacelles required input from various government and local authorities, with public safety always at the forefront,” explained Leighton Contractors Logistics Manager Brendan Rowe. “No less than four separate stakeholders were involved with every one of the 1,120 oversized loads delivered to the Macarthur Wind Farm site.”

Then, the project’s progress was almost thwarted by flooding that inundated the region during 2010–2011 because it significantly impacted the ability to build roads, hardstands, and foundations. “The excessive rainfall led to the redesign of the road and hardstand construction, as well as extensive dewatering of all excavations until the end of the 2011 winter,” said David Mawhinney, a project manager with Leighton Contractors. “The wet weather also held up the installation of the meteorological masts at the beginning of the project. These are installed to collect three months of wind data before the wind turbines are erected. Consequently, we took the unusual step of hiring a helicopter to pour the masts’ concrete foundations.”

Table 1. Macarthur Wind Farm project schedule. Source: Leighton Contractors

More to Come

For AGL, one of Australia’s largest private owners and operators of renewable energy assets, the now-completed Macarthur project serves as a “base” on which to build a sustainable energy future. But while Meridian funded its debt portion of the Macarthur investment with an award-winning project finance agreement, the company this June sold its interest in the farm to Malakoff Corporation Berhad, a Malaysian power generator and retailer.

According to Meridian Chief Executive Mark Binns, the company’s investment was intended to be held over the full-project term, but a “low interest rate environment and the opportunity to invest in further wind farms in Australia provided a compelling reason to look at a sale and the reinvestment of funds in future renewable generation options in Australia.” ■

Sonal Patel is a POWER associate editor (@sonalcpatel, @POWERmagazine).