The farming industry has been hit hard by the impacts of climate change. From increasing temperatures to severe droughts, farms face 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).
While agrivoltaics might sound complicated, it’s pretty 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 primary components of agrivoltaics!
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 developing 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!
With temperatures increasing and droughts intensifying, agrivoltaics will likely benefit many crops. When plants are photosynthesizing, they reach their "light saturation point." At this point, the plant has used as much sunlight as possible, and additional sunlight isn't benefiting the plant; instead, it's drying out the soil, making the plant thirstier and using 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 additional light stress and requiring more water. Some studies have also shown that in agrivoltaic systems, plants can produce more fruit, especially when the season has been particularly hot or dry. Plants also may grow 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, solar panels can 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.
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 also help the panels.
The plants transfer water from the soil into the atmosphere through evapotranspiration, which helps 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!
Now that you're generating all this efficient electricity, how can you profit from it? First, you can use the energy you produce to power your farm and 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 need. Fortunately, there are several 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. When your panels can't 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 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 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 enabling you to sell energy certificates to your utility. If your solar system produces more energy than you need to power your farm and you live in an area with an 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 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.
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 sell, it's important to answer a few questions first:
1. Will agrivoltaics work with my farm?
While agrivoltaics works with many different types of farms, it's not for everyone. If your crops require large equipment 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 well with agrivoltaics because they need full sunlight, and the shade can hinder their growth from the solar panels.
If your farm is primarily used for livestock grazing, agrivoltaics may also be unsuitable. 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 protect your solar systems further); the sheep can even use the panels for shade. However, cattle are prone to disturbing the solar systems and will likely be unable to roam among them safely.
2. How will the electrical connection work?
If your farm is close to power lines and electrical panels, you can connect your solar system to the power grid or a centralized power source. For truly remote farms, 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 vital to maintain this efficiency. Access to water or cleaning options will be essential 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 backward to calculate the number of panels you need to reach that output. To do so, you'll need to figure out your area's solar panel production ratio to understand how much energy a certain solar panel wattage will provide. Check out this article for a full explanation of how to work through this calculation. Remember that your panels will likely be extra efficient because of the plant's cooling effect.
5. How much will my solar installation cost?
The price of your installation will likely vary significantly 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, check if your state provides any incentive programs, as outlined above.
If you're looking to install solar panels on your home or barn roof, our Solar Calculator provides a free estimate of 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.