Slimline switchgear supports WA wind farm

ABB has been awarded a contract worth $4.5 million to supply power technology for the Collagar wind farm project, 25 km south-east of Merredin in Western Australia.

The project is the largest single-stage wind farm development currently under construction in the Southern Hemisphere and will displace more than a million tonnes of greenhouse gas emissions annually, equivalent to taking more than 250,000 cars off the road.

With 111 wind turbines, the farm will generate about 792,000 MW/h of renewable electricity per year, enough to power more than 125,000 homes.

The company will supply over 200 custom-built Safewind medium-voltage switchgear units to be installed inside the wind turbine towers. The units will isolate and switch the 33 kV reticulation power generated by the turbine.

All the live parts and switching components are protected in a stainless steel tank to ensure the highest levels of reliability and safety, as well as a long and trouble-free service life in the harsh and often inaccessible environments that are typical of wind farms.

Safewind, the company's latest product for wind farms, is 420 mm wide and small enough to fit through the narrow doorway of the turbine tower. This means it can be installed, if required, after the tower has been raised.

Traditional wind-turbine switchgear is not known for being slender, and certainly is not capable of fitting through a standard tower door without significant disassembly and site modifications. Rather, it is installed either inside the tower base or in a small secondary substation built alongside the tower.

In the former scenario, the equipment must first be placed on the base before the tower is fitted over the equipment, which presents costly challenges if modifications or retrofitting is ever required.

With wind turbine power outages from one tower alone potentially costing operators of the Collagar Windfarm up to $17,000  a week in lost generating capacity, installing this latest equipment ensures consistent and stable revenue by reducing possible generating downtime, says the company.

ABB was also selected to supply the electrical balance of plant (EBoP) by lead contractors Downer Engineering and Vestas Wind Systems. The facilities' substation will be fitted with ABB's 275 kV high-voltage equipment, current and voltage transformer disconnectors, earthing switches, surge arrestors and 33 kV primary switchgear distribution boards and distribution transformer for site power and auxiliary supplies.

In addition, two ABB 190 MVA power transformers, awarded under an earlier contract, will be installed at the wind farm to ensure the efficient transmission of renewable electricity into WA's south-west interconnected system power grid.

WA's renewable energy generated electricity from the region's main grid will rise from five to almost nine per cent when the wind farm comes online. Construction is expected to be complete by April 2012.

The state's energy retailer Synergy has signed a 15-year contract worth an estimated $1.5 billion to buy power from the farm that is based on 13,000 hectares of land. It is a venture being undertaken by UBS International Infrastructure Fund and Retail Employees Superannuation Trust in Western Australia.