segment two : Product Pathways
Wind turbine blades are big. But they don’t appear to be made of much, right? Not the case. If you were to peel back the layers, you’d discover a massive club sandwich of fiberglass, balsa wood, foam and more. Join us as we deconstruct a wind turbine blade, from a spinning source of energy down to its basic components.
A Wind Turbine from Finish to Start
Turbine blades. They're big, beautiful and part of an increasingly popular form of alternative energy. But how are such seemingly simple structures made? What are they made of? And where do their parts come from? Scroll to the right to uncover a deep, complex network of processes that will take you places you've never imagined.
Home Sweet Home
This is where turbines live and work. The open fields and hills are key for catching some major wind. But before these guys get spinning, they need to be assembled.
Watch our time-lapse video of a crew assembling six massive turbines in just two days.
On the Road
The journey involved in delivering a blade is not a typical road trip filled with I-spy and sing-alongs. It actually takes around six weeks to transport all nine parts.
See some ways we transport turbine blades.
Watch our friend Chris Lewis as he chronicles his trip, hauling a blade from its factory in Iowa to upstate New York.
The Finishing Touches
As you can see, the blade is fully assembled and nearly ready to go. But before it heads out with people like Chris, we need to make some finishing touches.
Workers perform stress testing on blades to make sure they can handle the elements. A 40 meter blade should be able to bend up to 17 feet at the tip under the maximum setting.
Blade joints are reinforced.
Then they’re balanced, sanded and painted.
Wrapping it Up
As we peel back the layers, you’ll notice a club sandwich of fiberglass and other materials. But before we can send our delicious sandwich on its way, we need to wrap it up for protection.
Many materials are fused together into one blade.
These are the shells of the blade, exposing our precious club sandwich.
Layers of dry glass fiber are laid into the mold with foam core in between.
Resin is infused into this dry sandwich to make a hardened fiberglass shell.
Two shell halves are joined like a clamshell and bonded together to form one blade.
Getting Down To The Core
As we dig deeper into our sandwich, you'll notice a cluster of stuff -- fiber glass, foam and other materials. This, my friends, is what we call the core.
This is what the core looks like before infusion, or the bonding process.
Workers inject resin between various layers of the core to fill in the gaps. Think of it like brick and mortar.
A Couple of Strong Spines
We've seen layer upon layer of stuff like fiberglass and foam. But what our blade really needs is a couple spines to give it some monster strength. This is where the spar caps come in.
Spar caps are made in their own molds.
The spar caps run along the inside of the blade, and are made of 67 layers of fiberglass.
To make the spar cap, layers of glass fabric are placed in a mold.
A bag is placed around the layers and infused with resin under a vacuum.
The spar cap is then removed from its mold and placed in the blade mold.
Holding down the Fort
As we dig deeper, you’ll notice a long I-beam structure in the middle called the shear web. This guy is made of foam and biax--a fiberglass material whose strength comes from its bi-directional composition.
The I-beam shape bridges both sets of spar caps, providing some superhero strength. With these two working together, you can bet this blade will stand up to all sorts of extremes.
The Root of All Greatness
At the base of every great blade is a root that holds it all together. This piece functions like the part of a bike spoke that fits into the axle--or what we call the hub. Overall, the root is strong enough to withstand hurricane winds that might occur only once in 50 years.
The root is around 90 layers thick and requires over 64 bolts to hold it in place.
Back to Where It All Began
And here we are, back to where it all began. As you can see, there’s a lot more involved in making a wind turbine blade than you probably would have guessed. But every step and material is very important. In a time when our resources are becoming limited, wind turbines are giving us more and more hope for the future of clean alternative energy.
Before you go, have a look at this animated video that recaps our entire journey from start-to-finish.