Iowa State University Research Finds Wind Farms Positively Impact Crops

Mar 06, 2018

By Ed Adcock

Iowa State University researchers have found that wind turbines located in agricultural fields are a plus for the crops growing around them.

The overall effects on crops growing in wind farms appear to be positive said Gene Takle, Iowa State agronomy professor. He has led a team of plant and soil scientists along with extension specialists who have been looking into the effects since 2009.

They started their work after seeing more wind farms and turbines pop up around the state. The new land use was positive for the landowners where they were located, but the researchers wondered if it was the same for the farmers growing crops.

“It’s unusual because we’re continuing the previous land use and we’re adding another,” he said. “We’re sort of double-cropping because these can be thought of two forms of energy production. The Chinese do this when they plant soybeans in between horticultural crops. We’re planting turbines.”

If the turbines change the microclimate for corn and soybeans, the team wanted to learn if it is a big enough change to be measured and the potential impacts.

He said wind blowing across a corn or soybean field without turbines creates a certain turbulence that carries moisture from the transpiring crop, which rises into the atmosphere and pulls down cooler, drier air. At night the wind is calmer and the land cools.

Turbines take some of the wind energy, slowing it down but increasing its turbulence so it interacts with the crop more, possibly increasing evaporation from the crop or moving carbon dioxide down into the crop.

“The biggest changes are at night and that’s because during the day there’s a lot of chaotic turbulence, just because the sun is heating the surface and the wind is gusty,” Takle said. “At night when it gets pretty calm, the crop cools down and if it’s a humid night you start to get dew formation. If you add the turbines, it looks a little more like the daytime. So the dew formation is delayed and it may start to evaporate sooner.”

Since fungus and mold like a wet environment, the shorter the wet period makes it less favorable for the growth of those potential pathogens. In the fall, the shorter wet period could speed up harvesting because farmers typically have to wait for soybeans to dry in the morning.

Another factor is that turbines bring warmer air down to interact with the cool air near the surface. Throughout the wind farm, the surface is a little bit warmer which inhibits dew formation.

“Satellites can measure surface temperatures and you can see little dots across the state of Iowa and locate every wind farm because they’re slightly warmer than the surrounding area. So we know it has an effect that’s large enough to be seen there,” he said.

Another plus is the air pressure fluctuation measured around wind turbines. Takle said there is a lot of carbon dioxide in the top few feet of soil — as much as two or three times what is in the air. The movement of air by the turbines pumps air down, and the movement draws carbon dioxide out of the soil so more would be available to the plant for photosynthesis.

The air moving down also creates more plant movement, which increases sunlight penetrating the dense crop canopy.

On the negative side is the tendency of higher temperatures occurring at night in wind farms.

Considering corn, during the day it’s taking in solar energy and carbon dioxide to make plant material. At night it cools down and gives back some of the carbon dioxide, and it gives up more if it’s warmer.

“So the night time warming of the turbines is not a totally good thing,” he said. “Night time temps have been going up over the last 40 years and are becoming a limiting factor for crop yields.”

But overall crops grown in wind farms seem to benefit.

“So there are three ways the crop is being ‘fertilized’ from either the air or from the soil or from increased photosynthesis. We measured increased carbon dioxide uptake during the day, but an increased respiration at night,” he said. “But over the course of the day there was more uptake. So as far as the impact of the turbines on the carbon dioxide processes and the photosynthesis process in the near vicinity of the turbines it’s a net gain.”

His team would like to look at the result of wind movement through a farm as it slows and tends to move up, which could create clouds if the air is warm and moist, and potentially rain.

“Are wind farms a preferential location for cloud formation or something that’s going to provide more rain in an area beyond the wind farm? We don’t know, we have some preliminary measurements that suggest that this is a real effect. Theoretically, you say yes there should be an effect, but is it large enough to be measured or to be important?” Takle asked.

Source: iastate.edu

Video: Why Your Food Future Could be Trapped in a Seed Morgue

In a world of PowerPoint overload, Rex Bernardo stands out. No bullet points. No charts. No jargon. Just stories and photographs. At this year’s National Association for Plant Breeding conference on the Big Island of Hawaii, he stood before a room of peers — all experts in the science of seeds — and did something radical: he showed them images. He told them stories. And he asked them to remember not what they saw, but how they felt.

Bernardo, recipient of the 2025 Lifetime Achievement Award, has spent his career searching for the genetic treasures tucked inside what plant breeders call exotic germplasm — ancient, often wild genetic lines that hold secrets to resilience, taste, and traits we've forgotten to value.

But Bernardo didn’t always think this way.

“I worked in private industry for nearly a decade,” he recalls. “I remember one breeder saying, ‘We’re making new hybrids, but they’re basically the same genetics.’ That stuck with me. Where is the new diversity going to come from?”

For Bernardo, part of the answer lies in the world’s gene banks — vast vaults of seed samples collected from every corner of the globe. Yet, he says, many of these vaults have quietly become “seed morgues.” “Something goes in, but it never comes out,” he explains. “We need to start treating these collections like living investments, not museums of dead potential.”

That potential — and the barriers to unlocking it — are deeply personal for Bernardo. He’s wrestled with international policies that prevent access to valuable lines (like North Korean corn) and with the slow, painstaking science of transferring useful traits from wild relatives into elite lines that farmers can actually grow. Sometimes it works. Sometimes it doesn’t. But he’s convinced that success starts not in the lab, but in the way we communicate.

“The fact sheet model isn’t cutting it anymore,” he says. “We hand out a paper about a new variety and think that’s enough. But stories? Plants you can see and touch? That’s what stays with people.”

Bernardo practices what he preaches. At the University of Minnesota, he helped launch a student-led breeding program that’s working to adapt leafy African vegetables for the Twin Cities’ African diaspora. The goal? Culturally relevant crops that mature in Minnesota’s shorter growing season — and can be regrown year after year.

“That’s real impact,” he says. “Helping people grow food that’s meaningful to them, not just what's commercially viable.”

He’s also brewed plant breeding into something more relatable — literally. Coffee and beer have become unexpected tools in his mission to make science accessible. His undergraduate course on coffee, for instance, connects the dots between genetics, geography, and culture. “Everyone drinks coffee,” he says. “It’s a conversation starter. It’s a gateway into plant science.”