What could be simpler than a wind turbine? Along comes a breeze, around goes the propeller, out comes the electricity. Sounds straightforward. But owners of wind farms know it’s a different story. When you’ve spent millions of dollars on each unit, you suddenly become acutely aware of the damage that can be done to those fast-spinning blades. Revenue forecasts can take a direct hit if these enormous devices aren’t kept in prime condition.
With nearly 8GW of wind projects generating in the NEM, 4GW under construction around the country and at least another 6GW in various stages of planning, the workload for specialised wind maintenance crews is set to grow very fast. But what does it take to do this type of work?
“If they have good hand skills and can work on the ropes or elevated work platforms, it’s work that’s there now,” says Chris Rose, the training and business development manager for wind energy at RIGCOM, a Sydney outfit certified by the Global Wind Organisation. “It’s going to be a growing industry over the next 10-15 years.”
Australia has plenty of gust and bluster but it’s also a tough environment for turbines, Rose says. A common problem is leading-edge erosion, a pitting on the blade towards the tips caused by rain and dust. “If it’s not looked after that can create structural damage,” Rose says. Blades can also suffer terrible damage if struck by lightning, and it’s not unknown for blades to be damaged during the long journey to Australian ports and projects far inland.
Damage suffered during transport is repaired before a blade is hoist into place. Other repairs are done the hard way, by dangling from a rope or elevated sky-high on a platform.
Wind turbine blades are a composite of fibreglass, balsawood and foam core. Some older blades contain a lot of balsa or foam, with what Rose says is a similar composite construction to a boat hull. More recently manufactured blades include carbon fibre. Rather than acting like propellers they work like wings of an airplane, where the passing wind lifts the blade so that it rotates around the axis. This means there is a pressure side and a suction side. The main structural element on each face, the spar caps, are connected inside the blade by shear webs that run the length of the blade.
Most blades, Rose says, are constructed the same way, an epoxy composite, although there are a couple of manufacture’s models with “a few secret tweaks to them”.
Anyone looking to move into the field should have International Rope Access Trade Association qualifications, and very good hand skills, preferably a trade background such as a carpenter or metalwork-type background using sanders and grinders. “Even guys from the marine industry with a boat-building background who can pick up a rope access ticket will be very desirable,” Rose says.
It sounds like hard work, way up in the air with a grinder then laying on sheets of gluey fibrous sheeting. “It’s very technical,” says Rose. “You’ve got to have a lot of confidence with grinders and sanders. The guys will take up a measured amount of resin for repairs, then finish them off and recoat them. It takes a lot of discipline.”
Graduates might find themselves employed by turbine manufacturers or a specialist contractor such as RIGCOM, which not only provides the training but offers the professional service under contract for clients such as Vestas and GE. “The industry is growing and the GWO passport is becoming a requirement for guys going out to work on the wind farms,” Rose says.
The 10-day course costs $4,995. Through its affiliation with the Global Wind Organisation course participants get a WINDA number, a passport linked to accreditation for first aid, safe handling and working from heights training.
The facility in Seven Hills, Sydney, includes a 6.5-metre section of tower and two 6.5-metre upright blade sections used for blade inspections, part of a more advanced course. Smaller 1.5-metre blade sections on trolleys are used for repair training.
And where did the blades come from? “I can’t tell you that,” Rose says. “It’s a secret. It took a long time to find them.”