Is it true we generate more wind energy in winter?

The change of the seasons means different things in different places. For the upper plains, which includes Iowa and Minnesota, winter weather generally brings higher wind energy production.

Wind is generated by the pressure caused by two air masses. The difference in pressure determines wind speed. Cold air is denser than warm air because the molecules are closer together. This means the same amount of wind can produce more power.

The faster, high-altitude air current known as the jet stream also shifts southward over parts of Iowa and Wisconsin during the cooler months. Under the right conditions, winds from the jet stream can reach the surface to power wind turbines.

At Alliant Energy, we have more than 1,800 megawatts of wind energy generation. According to data from the past three years, our wind projects generated an average of 88% more electricity per winter month than summer month. Thanks largely to increased wind production, 50% of the energy we distributed in 2022 came from renewable sources.

“We are proud of our progress in delivering low-cost, clean energy to our customers while keeping customer affordability top of mind,” said Mayuri Farlinger, vice president of customer and community engagement at Alliant Energy. “Our extensive wind fleet and renewable energy portfolio allows us to continue delivering on our purpose to serve our customers using reliable, clean energy sources.”

We weatherize our turbines to run in negative temperatures. In extreme conditions when there’s risk of generators overheating, we can shut them off or pitch the blades out of the wind to lessen the stress.

Occasionally it’s necessary to take our turbines offline for preventative maintenance or repairs. We generally do this in summer when winds are low. This is one reason it’s important to have diverse energy generation options to meet the needs of our customers.

Whatever the conditions, the renewable projects we operate generate low-cost electricity for our customers at all times of the year. Learn more about how these projects play a role in reliability through our Clean Energy Blueprint.