Imagine that you own a small, 20-acre farm in California’s Central Valley. You and your family have cultivated this land for decades, but drought, increasing costs and decreasing water availability are making each year more difficult.

Now imagine that a solar-electricity developer approaches you and presents three options:

• You can lease the developer 10 acres of otherwise productive cropland, on which the developer will build an array of solar panels and sell electricity to the local power company.
• You can select 1 or 2 acres of your land on which to build and operate your own solar array, using some electricity for your farm and selling the rest to the utility.
• Or you can keep going as you have been, hoping your farm can somehow survive.

Thousands of farmers across the country, including in the Central Valley, are choosing one of the first two options. A 2022 survey by the U.S. Department of Agriculture found that roughly 117,000 U.S. farm operations have some type of solar device. Our own work has identified over 6,500 solar arrays currently located on U.S. farmland.

Our study of nearly 1,000 solar arrays built on 10,000 acres of the Central Valley over the past two decades found that solar power and farming are complementing each other in farmers’ business operations. As a result, farmers are making and saving more money while using less water – helping them keep their land and livelihood.

A hotter, drier and more built-up future

Perhaps nowhere in the U.S. is farmland more valuable or more productive than California’s Central Valley. The region grows a vast array of crops, including nearly all of the nation’s production of almonds, olives and sweet rice. Using less than 1% of all farmland in the country, the Central Valley supplies a quarter of the nation’s food, including 40% of its fruits, nuts and other fresh foods.

The food, fuel and fiber that these farms produce are a bedrock of the nation’s economy, food system and way of life.

But decades of intense cultivation, urban development and climate change are squeezing farmers. Water is limited, and getting more so: A state law passed in 2014 requires farmers to further reduce their water usage by the mid-2040s.

The trade-offs of installing solar on agricultural land

When the solar arrays we studied were installed, California state solar energy policy and incentives gave farm landowners new ways to diversify their income by either leasing their land for solar arrays or building their own.

There was an obvious trade-off: Turning land used for crops to land used for solar usually means losing agricultural production. We estimated that over the 25-year life of the solar arrays, this land would have produced enough food to feed 86,000 people a year, assuming they eat 2,000 calories a day.

There was an obvious benefit, too, of clean energy: These arrays produced enough renewable electricity to power 470,000 U.S. households every year.

But the result we were hoping to identify and measure was the economic effect of shifting that land from agricultural farming to solar farming. We found that farmers who installed solar were dramatically better off than those who did not.

They were better off in two ways, the first being financially. All the farmers, whether they owned their own arrays or leased their land to others, saved money on seeds, fertilizer and other costs associated with growing and harvesting crops. They also earned money from leasing the land, offsetting farm energy bills, and selling their excess electricity.

Farmers who owned their own arrays had to pay for the panels, equipment and installation, and maintenance. But even after covering those costs, their savings and earnings added up to US$50,000 per acre of profits every year, 25 times the amount they would have earned by planting that acre.

Farmers who leased their land made much less money but still avoided costs for irrigation water and operations on that part of their farm, gaining $1,100 per acre per year – with no up-front costs.

The farmers also conserved water, which in turn supported compliance with the state’s Sustainable Groundwater Management Act water use reduction requirements. Most of the solar arrays were installed on land that had previously been irrigated. We calculated that turning off irrigation on this land saved enough water every year to supply about 27 million people with drinking water or irrigate 7,500 acres of orchards. Following solar array installation, some farmers also fallowed surrounding land, perhaps enabled by the new stable income stream, which further reduced water use.

Changes to food and energy production

Farmers in the Central Valley and elsewhere are now cultivating both food and energy. This shift can offer long-term security for farmland owners, particularly for those who install and run their own arrays.

Recent estimates suggest that converting between 1.1% and 2.4% of the country’s farmland to solar arrays would, along with other clean energy sources, generate enough electricity to eliminate the nation’s need for fossil fuel power plants.

Though many crops are part of a global market that can adjust to changes in supply, losing this farmland could affect the availability of some crops. Fortunately, farmers and landowners are finding new ways to protect farmland and food security while supporting clean energy.

One such approach is agrivoltaics, where farmers install solar designed for grazing livestock or growing crops beneath the panels. Solar can also be sited on less productive farmland or on farmland that is used for biofuels rather than food production.

Even in these areas, arrays can be designed and managed to benefit local agriculture and natural ecosystems. With thoughtful design, siting and management, solar can give back to the land and the ecosystems it touches.

Farms are much more than the land they occupy and the goods they produce. Farms are run by people with families, whose well-being depends on essential and variable resources such as water, fertilizer, fuel, electricity and crop sales. Farmers often borrow money during the planting season in hopes of making enough at harvest time to pay off the debt and keep a little profit.

Installing solar on their land can give farmers a diversified income, help them save water, and reduce the risk of bad years. That can make solar an asset to farming, not a threat to the food supply.

Jacob Stid works for Michigan State University. Funding for this work came from the US Department of Agriculture's National Institute of Food and Agriculture program and the Department of Earth and Environmental Sciences at Michigan State University. He also receives funding from the Foundation for Food and Agricultural Research.

Annick Anctil receives funding from NSF and USDA.

Anthony Kendall receives funding from the USDA, NASA, the NSF, and the Foundation for Food and Agricultural Research. He is an Assistant Professor at Michigan State University, and serves on the nonprofit board of the FLOW Water Advocates.