Towers Harness The Wind

It's the cleanest air on earth. And it's now helping Hydro Tasmania produce clean electricity. According to the air monitoring station at Cape Grim, the purity of the air that blows in from the Southern Ocean across the north-east tip of Tasmania is the cleanest that has ever been measured on the planet.

The new wind farm currently being developed at nearby Woolnorth will harness this wind for an eventual capacity of 130 megawatts of renewable energy.

The first stage of the Woolnorth Wind Farm commenced in August 2002, with six 1.75 megawatt wind turbines, each with a capacity of 1.75 megawatts. The farm is being developed by Hydro Tasmania, a renewable energy business, involved in the generation of hydro and wind power for the Tasmanian community. Vestas Wind Technology, a world leader in the wind power industry, is supplying all the wind turbines for the farm.

Construction of the second stage of the Woolnorth project began in September 2002. Tasmanian company, Haywards Engineering, are fabricating 31 wind towers for this stage, which will result in a capacity of 54 megawatta, and a 110 kilometre transmission line from Woolnorth to Smithton.

Haywards was awarded the A$10 million contract by Vestas to manufacture and deliver the 60 metre high wind towers to the Woolnorth site.

"This is a big job for us. We?ve got roughly 25 fabricators working on the project at any one time. It's the first time Haywards Engineering has manufactured wind towers, so there is a learning curve. However, we are experienced in the manufacture of medium to heavy industrial equipments, such as cooling towers, pressure vessels, stacks and so forth - so the job has been fairly straightforward for us," says Steve Edmund, Managing Director of Haywards Engineering.

With 80 employees working from its Launceston workshop, Haywards Engineering is one of Tasmania's leading steel fabrication and construction companies. "We?ve been involved in most of the major industrial projects in Tasmania," says Steve Edmund.

Haywards is producing 31 V-66 wind towers for the Woolnorth site. With a base diameter of 4 metres, the massive wind towers each consist of over 110 tonnes of steel. The blades measure 33 metres in length. The towers are constructed of 250 and 350 grade XLERPLATE® steel plate, produced by BlueScope Steel.

The 3500 tonnes of XLERPLATE® steel required for the project is being supplied by OneSteel, one of BlueScope Steel's distributors. The steel will be delivered to Hayward's Launceston factory already cut and beveled into the shapes required for fabrication, ready for rolling, welding and forming into towers. Each tower is constructed in 3 sections, fabricated individually, then transported by truck to the Woolnorth site.

"We use XLERPLATE® predominantly because it's a good quality product. What we?ve found is that lead times and delivery are very efficient, and also BlueScope Steel is flexible enough to adapt to our manufacturing schedule by producing plate of different grades and sizes. Each section of a wind tower requires a different grade of steel, so flexibility of supply is very important as far as we are concerned," says Steve Edmund.

"Having a reliable steel supplier is so important to our business. Steel is the only product that we work with - if we can?t depend on getting the right product at the right time - we don?t have a business. 90% of our steel is from BlueScope Steel, and we purchase about 5500 to 6000 tonnes a year," he adds.

The venture into wind technology has proved successful for Haywards. "The Woolnorth job has gone very well," says Steve Edmund. "We are very confident with the wind tower manufacturing process. During the last year we have also built two V52 60 metre towers for King Island's wind farm. And Onesteel has just recently supplied us with 1300 tonnes of XLERPLATE® to manufacture a further 12 wind towers for the Lake Bonney Wind Farm in South Australia."

Manufacture of the Woolnorth wind towers will be finished by the end of December 2003. The towers will be painted, assembled and delivered to site by the end of January 2004.

XLERPLATE® is a brand of high quality hot rolled plate steel products from BlueScope Steel.