Farms and agricultural enterprises are turning to solar energy in increasing numbers to power their daily operations. The cost of going solar has decreased, making more installations across the nation possible, in part due to investments made by the Solar Energy Technologies Office. Think about these issues as you decide what is best for you and your farm.
WHAT ADVANTAGES DO CO-LOCATING SOLAR AND CROP PRODUCTION OFFER?
Co-locating food production and solar energy has advantages for both farmers and solar energy companies.
Solar developers can gain from the following:
- Reduced installation costs – Using agricultural land that has already been tilled may save the requirement for pricey grading to level out the ground for use.
- Lower initial risk – Geotechnical hazards can raise the cost of solar installation because more testing is required. During a series of interviews with solar installers, it was determined that previously tilled agricultural land was the “least risk alternative.”
- Reducing the danger of upfront lawsuit during the environmental review process is one way solar installers might use already disturbed land.
- Increased solar performance and potential improvement in PV efficiency can both be attributed to vegetation growing beneath modules.
Agribusiness land managers can gain from:
- lower electricity prices.
- Stream of income diversification.
- An improved capacity to plant high-value, shade-resistant crops for new markets.
- Possibility to market to consumers who care about sustainability.
- The capacity to continue crop production while solar generation.
- Recharge damaged lands with nutrients and soil.
- Possibility of decreasing water use.
- Possibility of extending the growing season.
CONTAMINATION OF THE SOIL UNDERNEATH OR AROUND SOLAR MODULES
The most widely utilized solar photovoltaic technology is silicon-based PV cells. The majority of solar panels feature an aluminum or steel frame and a glass face that shields the PV cell. According to research, the sealed nature of the installed cells makes it unlikely that leaching of trace metals from modules will pose a serious problem.
Some solar panels employ cadmium telluride (CdTe). Studies have shown that even during fires, harmful cadmium compounds cannot escape from CdTe modules when they are operating normally. The compounds must be released from the modules at temperatures significantly greater than those used in grassfires.
CAN SOLAR MODULES AFFECT THE MICROCLIMATE UNDERNEATH THE MODULES AND IMPROVE INSECTICIDE, FUNGAL, NEMATODE, OR OTHER PEST PROBLEMS?
The effects of the microclimate beneath solar modules have received very little research, however the most recent findings indicate that there is little to no average impact. During the day, the air tends to be cooler under the panels, while at night, it tends to be warmer. According to one study, crop temperature, humidity, and air temperature in modules were comparable to those in full sun. According to this investigation, soil temperatures under the modules at night were lower than those under direct sunlight during the day. Studies have shown how native plants can survive beneath solar systems, but none have connected solar development with pest issues.
WILL VEGETATION OR CROPS UNDER SOLAR MODULES HEAT UP AND DRY OUT?
Due to shade from solar panels, crops and vegetation beneath will actually be cooled during the day and kept warmer at night. Studies have demonstrated that these temperature variances cancel out, resulting in mean daily crop temperatures under modules that were comparable to those in full sun, with no effect on crop growth rates. With the use of modules, farmers may diversify their crop choices, grow crops that can withstand some shadow, extend the growing season, and use less water. According to one study, lettuce grown under solar module shadowing had a crop weight that was at least as high as lettuce grown under full sunlight.
IS IT POSSIBLE FOR WILD ANIMALS SUCH AS ANTELOPES OR ELK TO GRAZE UNDER SOLAR MODULES?
Yes, however if a security barrier is wanted, larger animals can be kept out if they are thought to pose a threat to the modules’ integrity. It is possible to construct fencing to accommodate smaller animals like kit foxes. To offer habitat and forage for bees, birds, and other tiny species, areas beneath the modules can be reseeded.
ARE GROUND-MOUNTED SOLAR FACILITIES SUITABLE FOR GRAZING DOMESTIC ANIMALS SUCH AS SHEEP OR CALVES?
Sheep are frequently utilized at solar plants in the United States and Europe to reduce vegetation because they don’t climb on or damage the modules. Since vegetation is accessible beneath the modules at regular heights, it is not essential to raise the PV modules in order to allow for grazing. The possibility of module breakage makes cattle grazing incompatible with most PV systems. Due to a decrease in the requirement for mowing, herbicides, and other vegetation management methods, sheep grazing to control vegetation growth can be advantageous to local shepherds, solar operators, and the environment.
WHAT EFFECT DO SOLAR MODULES HAVE ON BIRD SPECIES OR OTHER WILDLIFE?
The presence of solar panels makes it possible for birds to interact. PV modules have been deployed and checked for avian effects at many airports because they tend to be less reflecting than windows. However, collisions with objects like electricity wires, cars, fences, and solar equipment and buildings like modules can cause bird injuries and even death. Although it hasn’t been verified, there are some worries that birds might mistake solar arrays for bodies of water and try to land on them. Bird collision danger from solar panels is very minimal, according to a 2017 comprehensive study of all solar and bird interactions in the UK. Infrastructure related to solar PV developments, including overhead power lines, is probably more likely to put birds in danger of colliding with them.
Other electrical devices like inverters and connection boxes, which make some noise, are needed to operate solar modules. The majority of inverters operate at 50-60 Hz, which is within the range of human hearing and significantly lower than the higher frequencies used to frighten animals. This frequency is the same as the AC electricity in your home or commercial structure. Sound is typically not audible at the edge of a fenced border, but if it is, it is typically not louder than background noise and gradually fades to inaudibility 50 to 150 feet away.
CAN NATURAL VEGETATION OR POLLINATOR HABITAT BE GROWN UNDER SOLAR MODULES?
Yes, native plants and animals that provide habitat for pollinators may coexist with solar systems. Low-growing vegetation can flourish beneath solar panels, reducing the need for mowing and preserving the panels’ visibility. Pollinator-friendly solar certificates have been created by two states (MN and MD) to encourage the establishment of pollinator habitat beneath utility-scale solar systems. Pollinator habitat can support beekeeping operations and assist nearby crops.
CAN SOLAR MODULES INCREASE FOOD PRICES?
There is no concrete proof that solar panels raise the cost of food. In fact, greater pollination and other helpful insect services provided by solar projects planted with pollinator habitat can assist increase local agricultural production. To encourage the planting of pollinator habitat that can benefit nearby farms, two states (MN and MD) have already created pollinator-friendly solar certificates.
Additionally, solar can offer agricultural land managers a number of advantages that might balance out the capital expenses of solar installation:
- Through leasing, solar energy systems can be installed for no money up front.
- Solar panels can be erected on unproductive farmland, giving the business another source of income. With this additional income, the farm’s operating costs can be reduced, and it will be able to weather difficult growing seasons.
- On current or anticipated growing areas, solar does not need to be installed.
- Co-locating solar and crop installations can be planned to produce the most food and electricity.
- High-value, shade-tolerant, and hand-harvested foods that might not often be accessible in markets can be planted under the solar modules’ shade (i.e. lettuces in desert areas, etc.).
CAN AGROCHEMICALS BE SPRAYED NEAR SOLAR MODULES?
To stop plant development, herbicide is currently applied around some solar modules. Agrochemicals shouldn’t be a problem. It is important to avoid spraying the modules directly, but if this does happen, they may be cleaned off with water because they are composed of glass, steel, or aluminum and are built to resist outside conditions.
DOES SOLAR POWER WORK TO POWER MY IRRIGATION EQUIPMENT?
Equipment for irrigation can really be powered by solar. Solar energy can run distant irrigation systems without a grid connection, balancing off the power needed for pumping. Currently, solar irrigation pumps are used in India, South America, and Africa.
MY FARMLAND IS LEASED DO I STILL GET TO INSTALL SOLAR PV?
Solar might or might not be permitted on the site depending on the lessee’s present land use. Solar power may be appropriate if the land is available or if the farming operations being conducted now are adequate.
MY TRACTOR CANNOT GO THROUGH OR AROUND SOLAR MODULES. DO YOU KNOW HOW I CAN STILL INSTALL SOLAR?
Solar panels can be set up on salt-degraded or marginal land as well as on the edges of fields where no farming is done. Smaller tractors or manual management are solutions for growing crops underneath and between solar modules. There is no one-size-fits-all solar design, and designers must take into consideration the needs of the land and farmers.
EVERY YEAR, I HAVE TO BURN MY FIELDS. CAN I INSTALLED SOLAR PV EVEN NOW?
Avoid burning vegetation close to or under solar arrays to prevent electrical fires and equipment damage. In spite of this, solar panels can still be put at a farming location. During the site selection phase, this requirement should be made clear to the solar developer in advance.
IN THE SPRING,MY FARMLAND FLOODS. CAN I INSTALLED SOLAR PV EVEN NOW?
Although electrical equipment must be built above the anticipated flood level, solar can be installed in flood plains. Raising equipment could result in higher installation costs and a less profitable project. The price of insurance will also be higher for PV systems located in a flood zone. PV installation may be more appropriate at a location that won’t flood.
WHAT EFFECTS DOES DUST HAVE ON SOLAR PV MODULE PERFORMANCE?
Estimates of the generation capacity of PV systems should take into account various levels of power generation loss as a result of soiling. Although the soiling loss used by NREL’s PV Watts soiling calculator is an average of 2%, local weather and soiling circumstances have a significant impact on this loss. The amount of dust and soiling on solar panels can be decreased by placing vegetation beneath and around the panels.
AFTER THE LIFE OF THE SOLAR SYSTEM, CAN MY LAND BE CONVERTED BACK TO AGRICULTURAL LAND?
At the conclusion of the solar installation’s operating life, the land can be returned to its original agricultural usage. The lifespan of a solar installation is typically 20 to 25 years, and throughout that time it can recover, raising the land’s future worth as an agricultural site. Resting soil can help keep it in good condition and increase the biodiversity of agricultural land. By growing crops like legumes underneath the solar array, you may enrich the soil with nutrients.
DO RAISING SOLAR MODULES TO SUIT CROP PRODUCTION IMPACTS OTHER RESOURCES?
The price of the solar installation may rise if the PV modules’ height is increased. The length of the steel fundamental posts underground would probably need to be expanded to withstand the additional structural loading caused by the increasing wind loading on higher constructions.