The farming industry has been hit hard by the impacts of climate change. From increasing temperatures to severe droughts, farms are facing new challenges that will likely increase with intensity as climate change progresses. Fortunately, a new solution is arising that can both benefit farmers and help reduce emissions: agrivoltaics (also known as dual-use solar).
What is agrivoltaics?
While agrivoltaics might sound complicated, it’s fairly straightforward when you break it down. “Agri” stands for agriculture, meaning food production. “Voltaics” stands for photovoltaic solar cells, or the technology that solar panels use to generate solar energy. Together, you have agriculture and solar panels: the two major components of agrivoltaics!
What does agrivoltaics look like?
At its simplest, agrivoltaics includes raised solar panels (typically five to ten feet above the ground) with plants growing underneath them. The panels are positioned at an optimal angle to allow just enough sunlight for the plants. Panel clusters are spaced a few feet apart to provide additional sunlight and space for farming equipment.
Many different types of farms can serve as land for development of these solar systems. Maybe your land is being used to provide grazing pastures for sheep. Perhaps you have a vineyard and are trying to grow grapes, which are particularly susceptible to the effects of climate change. You could have various crops, such as lettuce, tomatoes, corn, or more that don’t require full sunlight or large equipment for harvesting. Or, you could be trying to grow pollinator habitat to benefit your other crops or harvest honey. Many different agricultural practices are possible!
Will agrivoltaics improve your crop yield?
With temperatures increasing and droughts intensifying, agrivoltaics will likely be beneficial to many crops. When plants are photosynthesizing, they reach what is called their “light saturation point”. At this point, the plant has used as much sunlight as it can and additional sunlight isn’t actually benefiting the plant; instead, it’s drying out the soil, making the plant thirstier and using up more precious water resources.
In an agrivoltaics setup, panels are placed to optimize the amount of sunlight reaching the plants. They can reach their light saturation point without undergoing additional light stress and requiring more water. Some studies have also shown that in agrivoltatic systems, plants can produce more fruit, especially when the season has been particularly hot or dry. Plants also may produce larger leaves and spread out more with agrivoltaics to increase the surface area for photosynthesis.
In addition to keeping plants relatively cool during the day, the solar panels can also help keep them warm at night. The panels create a microclimate for the plants, resulting in similar average daily temperatures to areas without solar panels, but fewer fluctuations in the temperature between day and night.
How will plants affect solar energy output?
Remember learning about symbiosis during biology class? Symbiosis is a process by which two organisms mutually benefit from each other. Plants and solar panels form a relationship similar to symbiosis in agrivoltaics. As we explained above, while the panels keep the plants happy by keeping their soil moist, their photosynthesis efficient, and their temperatures relatively cool during the day and warm at night, the plants help the panels as well.
The plants transfer water from the soil into the atmosphere through a process called evapotranspiration, which helps to keep the panels cool during the day, allowing them to perform more efficiently and produce more energy. It’s a win-win for the panels and the plants!
How can you profit from the energy you produce?
Now that you’re generating all of this efficient electricity, how can you profit from it? First, you can use the energy you produce to power your farm and/or your home if you live on the farm. In this way, you can substantially lower your electric bills. However, if you have a large system, you’ll likely generate more energy than you actually need. Fortunately, there are a number of ways you can store or sell this extra energy:
Net metering is a solar incentive that allows you to store excess energy that your panels generate in the grid. In turn, you receive credits. During times when your panels aren’t able to produce enough electricity to power your farm, you’ll use these credits to offset the costs of electricity that you need to pull from the grid. Not all states have net metering policies, so be sure to check out the list of qualifying states in this article to see if this policy could benefit your farm.
You may also choose to install battery storage with your solar panel system to store excess solar electricity produced during the day, which you can then use after the sun goes down. Storage can be a great option if you live in an area that frequently experiences grid blackouts as it will allow you to continue powering your farm with your solar panels. It can also be a good choice if your state doesn’t have a net metering policy. Check out this article to learn more about battery storage and decide if it’s a good fit for your farm.
Solar Renewable Energy Certificates, or SRECs, are another solar incentive that can enable you to sell certificates for energy to your utility. If your solar system produces more energy than you need to power your farm and you live in an area with a SREC market, you may be able to make a substantial profit, thereby diversifying your revenue stream. You can visit the Database of State Incentives for Renewables & Efficiency (DSIRE®) to learn more about financial incentives that are available in your state.
You also may be able to make a substantial profit by allowing your farm to be used for community solar. Community solar allows people in your community to purchase and benefit from the solar produced by your agrivoltaics system. Participants often pay less through community solar than they would through their utility.
Adding solar to your farm: questions to answer
When deciding if adding solar to your farm will help by improving your crop yield, reducing your water consumption, and efficiently producing renewable electricity that you can use and/or sell, it’s important to answer a few questions first:
1. Will agrivoltaics work with my farm?
While agrivolatics works with many different types of farms, it’s not for everyone. If your crops require large equipment that need to fit between the solar panel systems, you may need to limit your arrays to certain areas on your farm, which may or may not be a viable option. Agrivoltaics also won’t work with crops that require seasonal burning as this can pose an electrical hazard. Some crops, such as wheat, don’t work as well with agrivoltaics because they require full sunlight and their growth can be hindered by the shade from the solar panels.
If your farm is primarily used for livestock grazing, agrivoltaics also may not be suitable. Agrivoltaics has been shown to work well with animals such as sheep because they generally don’t disturb the panels and wiring (you can also install fencing to further protect your solar systems); the sheep can even use the panels for shade. However, cattle are prone to disturbing the solar systems and will likely not be able to safely roam among them.
2. How will the electrical connection work?
If your farm is close to power lines and electrical panels, you’ll be able to connect your solar system to the power grid or to a centralized power source. For farms that are truly remote, agrivoltaics may not benefit your farm.
3. Will my panels become covered in dust?
Your panels should be able to work efficiently (likely even more efficiently) on your farm, but cleaning them is important to maintain this efficiency. Having access to water or cleaning options will be important to keep your panels working efficiently.
4. How many panels will I need?
First, you’ll need to determine how many kilowatt hours of energy you need (or want) to generate. From there, you can work backwards to calculate the number of panels you’ll need to reach that output. In order to do so, you’ll need to figure out the solar panel production ratio for your area to understand how much energy a certain solar panel wattage will provide. Check out this article for a full explanation on how to work through this calculation. Keep in mind that your panels will likely be extra efficient because of the plants’ cooling effect.
5. How much will my solar installation cost?
Your installation will likely vary greatly in price depending on the solar developer you choose; therefore, it’s important to explore options and get quotes from multiple companies before deciding on a contractor. Also make sure to check if your state provides any incentive programs, as outlined above.
If you’re looking to install solar panels on the roof of your home or barn, our Solar Calculator provides a free estimate for what this system might cost, when you could break even on the investment, and how much money you could save over time. If you’re interested in joining community solar, visit our network of community solar providers.