Understand Wind Energy
Welcome to Energy Spotlight from Stanford University's Understand Energy Learning Hub! Our goal is to help you get up to speed on the complex world of energy in a fast and fun way. This issue covers wind energy. If you like what you see, please share widely and encourage others to subscribe. You can also check out all of our past issues!
Wind: What you need to know
Significance: Wind accounts for 8% of global electricity generation. China is the largest producer, generating over a third of global wind electricity. In the United States, wind is the largest source of renewable electricity, meeting 10% of the country's electricity needs.
Wind energy is the second fastest growing electricity resource behind solar PV. Global installed wind capacity grew by almost 15% last year!
How does it work? Wind turbine blades are like airplane wings—fat in front and tapered at the back. Air moving over wind turbine blades goes faster over the tops of the blades, causing them to “lift” and spin, rotating a shaft inside the nacelle that is connected to a generator. The result? The kinetic energy of wind is converted into electricity on the grid. And for every doubling of wind speed, the power of the wind increases eightfold. So, having access to strong wind matters. You can check out this TED Talk about how wind turbines work.
Where are wind turbines made? Chinese companies dominate wind turbine manufacturing. Six of the top ten manufacturers are Chinese companies.
Drivers: No carbon dioxide is emitted when wind turbines generate electricity, making them a powerful climate solution. And it's low cost. The cost to produce onshore wind in the U.S. has fallen 65% over the past 15 years as improvements in technology, greater investment, and economies of scale have made building wind farms more economical. Building a new wind farm in the U.S. is less expensive than any other form of electricity generation. (The levelized cost of energy for wind is $25-$75/MWh vs. coal at $70-$170 and solar PV at $30-$90.) Also, the fuel (wind) is free forever, unlike other resources such as fossil fuels.
Barriers: Wind turbines can only generate electricity when the wind is blowing. However, grid operators have ways to manage wind's intermittency, including energy storage, grid expansion, and demand response, which is the reduction or shifting of electricity usage during peak periods of demand. Wind turbines can also endanger bird and bat populations. You can check out the "avian and bat concerns" section of our Fast Facts About Wind Energy to put this in context. Solutions like AI are being deployed to reduce this negative impact.
Wind: Future trends
Capacity: Countries are betting big on wind as a way to clean up their power grids. The International Energy Agency projects that, in a world on track for net-zero emissions by 2050, the amount of installed capacity would nearly triple – from 1,000 GW to 3,000 GW – by 2030.
Technology: In 1990, the average wind turbine was just under 200 feet tall. Today, the average turbine is well over 300 feet tall or about the length of a football field. Wind speeds are stronger and steadier higher up, so taller turbines can generate more electricity.
Offshore: Some of the best wind resources can be found over the oceans. Challenging conditions, lack of port infrastructure, and equipment corrosion can make building and operating wind farms offshore difficult, but improvements in technology and construction techniques have enabled a tripling in global offshore wind capacity in just the last five years. Offshore wind accounts for less than 10% of wind capacity globally, but major projects are under construction in Europe, East Asia, and the United States. Learn more about the world's largest offshore wind farm.
Resource: Shifting wind patterns due to climate change can negatively impact wind electricity generation. For example, 6 GW of wind energy capacity were added in the U.S. in 2023, but U.S. wind generation declined for the first time since the 1990s due to a decrease in wind speeds caused by El Niño.
In the News
News: A new federal lease will facilitate one of the first floating offshore wind projects in the United States. Twelve floating offshore wind turbines capable of generating 144 MW of electricity are planned to be built off the coast of Maine as a proof of concept. Check out this article about Maine's offshore plans.
Context: Offshore wind is easiest to develop in shallow waters (less than 50m) where the turbines can be driven directly into the ocean floor. Floating wind turbines can be used in waters as deep as 300m, allowing development of offshore wind energy in more places. However, keeping floating wind turbines stable is extremely difficult. Imagine trying to balance a 350-foot pole with blades spinning around on a floating raft with waves. That is an engineering challenge to say the least.
Fun Fact
Wind turbine blades can be up to 350 feet long and must be transported to the wind farm in a single piece. That can be a challenge for developers. Think about navigating a winding road with a blade the length of a football field! A new company called Radia thinks it has the solution: build the world's biggest airplane. Learn more about this intriguing startup.
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The data in this issue are current as of September 2024. For the most current data, visit our Wind Energy Fast Facts.
