Wind Power
This training reviews how wind power will contribute to a clean and stable electric grid. This training is part of a series of trainings on achieving a clean electric grid and some of the main technologies that will get us there.
Background on wind power
To generate electricity, wind turbines usually have propeller-like blades that are turned by the wind, which spin a generator to create electricity. The first wind turbine used to generate electricity was built in 1887. Most wind turbines to date have been installed on land, but offshore wind is growing rapidly so that we can harness the high speed and energy of ocean winds. 
In most cases, offshore wind turbines are secured to the ocean floor and undersea cables transmit their electricity. In areas with deep offshore waters like the U.S. west coast, floating wind turbines can be a more practical option. In this case the turbine is mounted on a floating structure with lines anchored to the seabed below. The first floating wind turbine was installed off the coast of Scotland in 2017.
How wind power supports a clean and stable electric grid
Once a wind turbine is installed, it produces essentially no climate pollution (aside from the energy needed to maintain and eventually decommission the system). The blades simply spin in the wind and turn it into clean electricity.
Wind turbine prices have declined by about 50% since 2008. In fact, onshore wind is now the second-cheapest source of new electricity in the U.S. on average, just behind solar energy (see the FAQ below for more on cost comparisons). As a result, wind energy accounted for 32% of the new electricity generation capacity added to the U.S. power grid in 2021. Overall, wind energy accounts for nearly 11% of all electricity generated in the U.S.
Issues with wind power
The primary issue with wind power lies in its intermittency and variability — wind doesn’t blow at a consistent speed. This issue can be alleviated through a variety of approaches, including by coupling wind turbines with energy storage systems, complementing them with firm power sources (i.e. geothermal power, hydroelectricity, nuclear power, and bioenergy and gas with carbon capture), spreading out wind and solar farms (which often produce peak power at different, complementary times) over large geographic areas connected by long-distance transmission lines, and implementing electricity demand response.
Siting wind farms also requires a significant amount of land area. The 2021 Princeton Net-Zero America report estimated that in total, the visual footprint of the amount of wind turbines needed to reach net-zero emissions would require 2.5% to 10% of total U.S. land area. The direct land use from the wind turbines themselves would be much smaller, as illustrated in the dark blue box in the figure below from the report.
To reduce the land use impact of wind farms, the land between individual turbines can be used for other purposes like growing crops or grazing livestock. Leasing land for wind turbines can provide stable extra income for farmers and ranchers.
Sometimes local opposition can block the installation of wind facilities. Between 2015 and 2022, local governments rejected nearly 50 wind projects per year. This opposition is often catalyzed by anti-renewable energy groups, based on a mix of legitimate concerns about land use and misinformation about the environmental and health impacts of wind turbines. This local opposition can be countered by other local residents expressing their support for wind projects.
How much could wind power contribute to a clean and stable electric grid?
According to the Princeton Net-Zero Report, in 2050 the U.S. will need 6 to 28 times more wind power than today in order to reach net-zero emissions depending on the scenario. That’s between 567 and 2,650 gigawatts (compared to about 95 gigawatts in 2021), accounting for between 24% and 43% of America’s total electricity generation in 2050.
The large range depends on a variety of factors. For example, how much total electricity is needed, which depends on how much each sector of the economy electrifies, how fast we can install new wind farms, and how much electricity demand is met by other technologies. The animation below illustrates the amount of wind energy (in blue) and solar energy (in orange) and transmission lines the U.S. will need to add every decade 2020 through 2050 in one net-zero scenario.
Other FAQs
What about claims that wind turbines are bad for the environment?
Every item we use requires raw materials that need to be mined and manufactured into a final product. Wind turbines particularly need steel, copper, zinc, and several rare earth metals. These mining and manufacturing activities have environmental and carbon footprints.
But those impacts are vastly less than those from the fossil fuel energy they will replace. For example, nearly 8 billion tons of coal were mined and over 4 billion tons of crude oil were extracted from the ground in 2020 alone globally. For comparison, the World Bank estimates that a pathway to meet the Paris targets would require less than 3.5 billion tons of minerals in total over the next three decades.
To generate energy from fossil fuels, we have to burn them and then extract more from the Earth in a never-ending cycle. Conversely, the minerals to make a wind turbine only have to be extracted once, and then most of the materials — including the blades — can be recycled.
What about claims that wind turbines kill birds?
Although no one has a precise number, the American Bird Conservancy estimates that U.S. wind turbines are responsible for approximately 1 million bird fatalities per year. While that’s a large number, it’s a small fraction of the estimated 2.5 billion birds killed by domestic cats and 600 million killed in collisions with buildings. And the Audubon Society estimates that two-thirds of America's birds are threatened with extinction due to climate change, which wind turbines help ameliorate.
Scientists are exploring ways to reduce bird deaths caused by wind turbines, for example potentially by painting a turbine blade black and avoiding locations where lots of birds are known to fly. There are also indications that birds are already learning how to avoid turbine blades just like, over time, they learn how to avoid predators.
What about claims that wind turbines kill whales?
Since 2016 there has been an unusually high mortality rate for whales along the Atlantic coast, and some individuals (including some groups funded by the fossil fuel industry) have tried to place the blame on offshore wind development. But of the autopsies conducted on recovered whale bodies, scientists concluded that “To date, no whale mortality has been attributed to offshore wind activities.”
Experts posit that the whale population has grown in recent years, and more are following prey closer to shore due to warming ocean waters, resulting in more deaths from collisions with human vessels and fishing gear entanglements.
How do wind costs compare when including backups?
Comparing costs between different energy generation technologies is a challenge. Because wind energy is variable, by itself it can’t fully displace a consistent on-demand “dispatchable” source of energy like fossil fuels or clean firm alternatives. But because the U.S. does not yet put a price on carbon pollution, fossil fuel energy doesn’t reflect the additional costs associated with its climate damages.
As our deployment of wind energy ramps up, it can simply begin to displace some of the generation from more expensive alternatives. For example, fossil fuel power plants could run less often during times of higher wind speeds. But as wind power becomes a significant percentage of the overall electricity supply, it will more often need to be combined with complementary technologies like energy storage to address the intermittency issue. However, short-term battery storage works better for solar energy, which only needs a few hours of energy storage until the sun sets, than for wind energy, which generally requires longer-term storage. Building more electricity transmission lines to share extra wind energy can be more cost-effective, but that’s a slow process.
In short, it’s challenging to estimate the costs of addressing wind intermittency because there are a variety of potential solutions.