Wind turbines have become bigger, more powerful, and more cost-efficient to operate in recent decades.
A key improvement has been modern blades that are far more sophisticated in design, from aerodynamic properties to materials. This has enabled a variety of other improvements to the turbine, including greater size and more height (which means the turbine can tap higher wind speeds), with less noise.
Here’s how the blades have evolved and some key changes that have enabled the scaling up.
Wind
turbine
blade
853-foot
height
Forty years ago typical wind-turbine blades were around 26 feet long. Today, with lighter materials, the blades have reached 351 feet, longer than the Statue of Liberty is tall, and are packed with new technology.
15,000
kilowatts
of power
75 kW
55 feet
The materials
Low-pressure
skin
305 feet
Statue of
Liberty
Fiberglass,
balsa and foam
High-
pressure
skin
Adhesive bonds
The blade is constructed in two parts. The adhesive bonds stand up to 4,000 pounds per square inch of stress.
1980
Early wind-turbine blades were made from fiberglass and resin. The materials limited their size and thus their power output.
Fiberglass
2021
Modern blades, made from carbon fiber and other advanced materials, are 90% lighter than 1980s blades would be if scaled to current turbine sizes. Because of their size and design, turbines with the new blades can produce up to 15,000 kW of energy.
Carbon
fiber
Spar cap
This section of the blade takes an enormous amount of stress. It is now reinforced with a carbon-fiber strip the entire length of the span for strength. Sometimes the strip is made with carbon-fiber planks instead of cloth.
Prefabricated
carbon-fiber
planks
Innovations for the modern wind-turbine blades include higher strength that can withstand more stress, bend-twist coupling to reduce loads, and aerodynamic improvements to the blade tip for noise mitigation.
Blade tip
Since the blade tip moves faster than the blade nearest the hub, more noise is generated on the tip.
Tip shape
Rounded tips and serrated edges make blades quieter.
Bend
Greater swept area captures more wind, but requires longer blades that are more slender and flexible in bending. Manufacturing in a bend in the blade (known as a pre-bend) allows more room to deflect while avoiding contact with the tower.
Twist
Passive bend-twist coupling reduces the sensitivity to natural turbulence in the wind and allows even longer blades without increasing the weight.
New attachments
Blades were attached to the hub first with bolted flanges, then using heavy T-bolts. Inserts are a lighter alternative that is even stronger.
Front
view
Front
view
Wind
turbine
blade
853-foot
height
Forty years ago typical wind-turbine blades were around 26 feet long. Today, with lighter materials, the blades have reached 351 feet, longer than the Statue of Liberty is tall, and are packed with new technology.
15,000
kilowatts
of power
75 kW
55 feet
The materials
305 feet
Statue of
Liberty
Low-pressure
skin
Fiberglass,
balsa and foam
High-
pressure
skin
Adhesive bonds
The blade is constructed in two parts. The adhesive bonds stand up to 4,000 pounds per square inch of stress.
1980
Early wind-turbine blades were made from fiberglass and resin. The materials limited their size and thus their power output.
Fiberglass
2021
Modern blades, made from carbon fiber and other advanced materials, are 90% lighter than 1980s blades would be if scaled to current turbine sizes. Because of their size and design, turbines with the new blades can produce up to 15,000 kW of energy.
Carbon
fiber
Spar cap
This section of the blade takes an enormous amount of stress. It is now reinforced with a carbon-fiber strip the entire length of the span for strength. Sometimes the strip is made with carbon-fiber planks instead of cloth.
Prefabricated
carbon-fiber
planks
Innovations for the modern wind-turbine blades include higher strength that can withstand more stress, bend-twist coupling to reduce loads, and aerodynamic improvements to the blade tip for noise mitigation.
Blade tip
Since the blade tip moves faster than the blade nearest the hub, more noise is generated on the tip.
Tip shape
Rounded tips and serrated edges make blades quieter.
Bend
Greater swept area captures more wind, but requires longer blades that are more slender and flexible in bending. Manufacturing in a bend in the blade (known as a pre-bend) allows more room to deflect while avoiding contact with the tower.
Twist
Passive bend-twist coupling reduces the sensitivity to natural turbulence in the wind and allows even longer blades without increasing the weight.
New attachments
Blades were attached to the hub first with bolted flanges, then using heavy T-bolts. Inserts are a lighter alternative that is even stronger.
Front
view
Front
view
853-foot
height
Wind
turbine
blade
Forty years ago typical wind-turbine blades were around 26 feet long. Today, with lighter materials, the blades have reached 351 feet, longer than the Statue of Liberty is tall, and are packed with new technology.
15,000
kilowatts
of power
75 kW
55 feet
305 feet
Statue of
Liberty
The materials
Low-
pressure
skin
Fiberglass,
balsa and foam
High-
pressure
skin
Adhesive bonds
The blade is constructed in two parts. The adhesive bonds stand up to 4,000 pounds per square inch of stress.
1980
Early wind-turbine blades were made from fiberglass and resin. The materials limited their size and thus their power output.
Fiberglass
2021
Modern blades, made from carbon fiber and other advanced materials, are 90% lighter than 1980s blades would be if scaled to current turbine sizes. Because of their size and design, turbines with the new blades can produce up to 15,000 kW of energy.
Carbon
fiber
Spar cap
This section of the blade takes an enormous amount of stress. It is now reinforced with a carbon-fiber strip the entire length of the span for strength. Sometimes the strip is made with carbon-fiber planks instead of cloth.
Prefabricated
carbon-fiber
planks
Innovations for the modern wind-turbine blades include higher strength that can withstand more stress, bend-twist coupling to reduce loads, and aerodynamic improvements to the blade tip for noise mitigation.
Blade tip
Since the blade tip moves faster than the blade nearest the hub, more noise is generated on the tip.
Tip shape
Rounded tips and serrated edges make blades quieter.
Bend
Greater swept area captures more wind, but requires longer blades that are more slender and flexible in bending. Manufacturing in a bend in the blade (known as a pre-bend) allows more room to deflect while avoiding contact with the tower.
Twist
Passive bend-twist coupling reduces the sensitivity to natural turbulence in the wind and allows even longer blades without increasing the weight.
New attachments
Blades were attached to the hub first with bolted flanges, then using heavy T-bolts. Inserts are a lighter alternative that is even stronger.
Front
view
Front
view
853-foot
height
Wind
turbine
blade
15,000
kilowatts
of power
75 kW
55 feet
305 feet
Statue of
Liberty
Forty years ago typical wind-turbine blades were around 26 feet long. Today, with lighter materials, the blades have reached 351 feet, longer than the Statue of Liberty is tall, and are packed with new technology.
The materials
Fiberglass,
balsa and foam
Adhesive bonds
The blade is constructed in two parts. The adhesive bonds stand up to 4,000 pounds per square inch of stress.
1980
Early wind-turbine blades were made from fiberglass and resin. The materials limited their size and thus their power output.
Fiberglass
2021
Modern blades, made from carbon fiber and other advanced materials, are 90% lighter than 1980s blades would be if scaled to current turbine sizes. Because of their size and design, turbines with the new blades can produce up to 15,000 kW of energy.
Carbon
fiber
Spar cap
This section of the blade takes an enormous amount of stress. It is now reinforced with a carbon-fiber strip the entire length of the span for strength. Sometimes the strip is made with carbon-fiber planks instead of cloth.
Prefabricated
carbon-fiber
planks
Innovations for the modern wind-turbine blades include higher strength that can withstand more stress, bend-twist coupling to reduce loads, and aerodynamic improvements to the blade tip for noise mitigation.
Blade tip
Since the blade tip moves faster than the blade nearest the hub, more noise is generated on the tip.
Tip shape
Rounded tips and serrated edges make blades quieter.
Front
view
Bend
Greater swept area captures more wind, but requires longer blades that are more slender and flexible in bending. Manufacturing in a bend in the blade (known as a pre-bend) allows more room to deflect while avoiding contact with the tower.
Twist
Passive bend-twist coupling reduces the sensitivity to natural turbulence in the wind and allows even longer blades without increasing the weight.
New attachments
Blades were attached to the hub first with bolted flanges, then using heavy T-bolts. Inserts are a lighter alternative that is even stronger.
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