Arable land is always at a premium. Since the last ice age, humans have cleared one-third of the earth’s forests and two-thirds of its wild grasslands, much of it for agriculture. And as the world’s population – 8 billion last November – continues to expand, there is increasing pressure on farmland to produce not only more food but clean energy as well.
In places like Yakima, Washington, it has created competition for space as land-hungry solar arrays gobble up available fields. Last month, the state’s Energy Facility Site Evaluation Council approved plans to cover 1,700 acres of agricultural land with photovoltaic (PV) panels, lifting the county’s moratorium on solar projects and fueling community concerns about the long-term effects of losing cropland.
A recent study by the University of California, Davis, however, shows how farmers may soon be able to harvest crops and energy together, on common land. Researchers concluded that bands within the visible light spectrum can be filtered and harnessed separately – blue light waves to generate solar power and red light waves to grow fruit and vegetables – to maximize the use of farmland, all while reducing heat stress and reducing crop waste.
“Why does [agriculture] have to be a zero-sum game if we can optimize the land for both?” asks Majdi Abou Najm, an associate professor in UC Davis’ Department of Land, Air and Water Resources and an Environment Institute fellow, who co-authored the paper.
Photons, or the particles that make up light, have different properties, he explains: Blue ones have higher energy than their red counterparts, resulting in light with a shorter wavelength and higher frequency. While that gives blue light the jolt it needs to generate power, the extra pulse also results in higher temperatures.
“From a plant perspective, red photons are the efficient ones,” Abou Najm said. “They don’t make the plant feel hot.”
Through computer modelling, Abou Najm and lead author Matteo Camporese, associate professor in the Department of Civil, Environmental and Architectural Engineering at the University of Padova, found that applying red light waves to plants increases photosynthesis and carbon assimilation – the process they metabolism. carbon dioxide into organic compounds – while reducing transpiration. In other words, under the cooler spectrum, “crops can get the same amount of CO2 using less water,” he said.
Although their research was inspired by hydroponic light applications used in indoor farming systems, “those have a high energy cost,” says Abou Najim. “We decided to use sunlight as our input.”
One of the main goals of the study, says Abou Najim, is to “encourage the industry to create a new generation of solar panels.” Camporese sees potential in organic solar cells, which, unlike the shiny, metallic, silicon-based surfaces, are derived from carbon compounds. Thin and transparent, the cells are applied as a film on various surfaces, including glass. This technology could be used to develop photo-selective PV panels that filter out blue light to generate power, he said, while transmitting the red spectrum to crops planted directly below.
Tomatoes grown under the solar panels that filter light. Photography courtesy of UC Davis.
In fact, the growing field of voltaic agriculture, where land is used for food production and energy production, has made land use more efficient by spreading conventional solar arrays between rows of crops. (Solar grazing is a variation where livestock graze between the arrays.) The angled panels shade leafy vegetables and fruit which are sensitive to heat from the most intense rays of the day; the plants, meanwhile, transfer moisture and lower the temperature under the heat-sensitive cells, thereby improving their performance.
However, the plants grown through agrivoltaics are grown in partial shade, and “less light usually means less yield,” says Camporese. This effectively puts a limit on the density of solar panels and plants on cogeneration farms. But transparent arrays would allow for both areas to be fully covered, he notes, maximizing land use and giving a big boost to productivity per acre.
Last May, the researchers conducted a limited field study of photo-selected crops at the UC Davis Agricultural Experiment Station. The team planted processing tomatoes – a common crop from the Sacramento Valley – in small plots of equal size, one with a photo-filtered red canopy, another with blue and a third remaining uncovered as a control.
After about four months, including the hottest weather on record at the beginning of September, the two filtered plots were each yielding about a third less than the uncovered one. Yet, when sorted for quality – ripe, unripe or “bad” – the control plot accounted for twice as many rotten tomatoes. “So the filters helped reduce heat stress,” said Abou Najm, and “cut waste [yield] by more than half.”
Add energy production on top and the net gains would more than compensate for the smaller harvest, he said. By co-locating crops and solar generation, “100 percent becomes a very low number when you can get 120- or 140-percent yield.”
And for countries and regions facing a tight squeeze on farmland, that makes increased production even more valuable, especially given that producing clean energy requires 10 times more land per unit of power than fossil fuels.
Abou Najm also sees the canopy approach as a way for farmers to build climate resilience. Solar filtering helps the soil retain moisture and protect farm workers from harsh rays, while lower transpiration means crops need less water. And by producing their own power, farmers could offset rising energy costs and push the industry to embrace electric tools and vehicles, he adds.
“By 2050, we will have [an additional] two billion people on this planet, and we will need 60 percent more food, 40 percent more water and 50 percent more energy” than is produced on right now, said Abou Najm. Research needs to happen at a transformative level in order to meet those ballooning needs.
By maximizing the solar spectrum, “we are making the most of an endless sustainable resource,” he adds. “If a technology takes off that can develop these panels, then the sky’s the limit on how optimized we can be.”
Do solar panels ruin farmland?
Do solar panels pollute the land? Solar panels contain photovoltaic (PV) cells that convert sunlight into electricity. When these panels go to landfill, valuable resources are wasted. See the article : Why solar energy is environmentally friendly ?. And because solar panels contain toxic materials like lead that can leach out as they break down, landfilling also creates new environmental hazards.
Do solar farms depreciate property? It is a common misconception that ground-based solar farms reduce the value of nearby properties. An examination of property values in states across the United States shows that large-scale solar arrays often have no measurable effect on nearby property values, and in some cases can even have positive effects.
Do solar farms harm the land?
The clearing and use of large areas of land for solar energy facilities can adversely affect native vegetation and wildlife in many ways, including loss of habitat; interference with rainfall and drainage; or direct contact causing injury or death. Read also : Mississippi utilities are battling the state’s effort to increase solar power on rooftops.
Do solar farms contaminate the soil? Finally, most solar farms are indeed safe to operate. However, potentially toxic heavy metals and silicon by-products are used in these projects. Damaged units or time can release these contaminants into the environment. Therefore, consider taking soil samples to monitor for potential contaminants.
What are the disadvantages of living near a solar farm? There may be some disadvantages to living next to a solar farm, including disturbance to local habitats, less farmland resulting in poor views, and possible electromagnetic waves from solar batteries. Although no source of power is perfect, solar power is known as the safest source of energy.
Are solar farms harmful?
Electricity from solar panels and transmission to the power grid emits extremely weak electromagnetic fields. Exposure to low-level electromagnetic fields has been extensively studied, and there is no evidence that it is harmful to human health, according to the World Health Organization (WHO).
Do solar farms emit toxic chemicals? As solar panels sit in landfills, the toxic metals they contain can leach out into the environment and potentially pose a public health hazard if they enter the groundwater supply.
What happens to the soil under solar panels?
Areas under solar PV panels maintained higher soil moisture throughout the observation period. There was also a significant increase in end-of-season biomass for areas under the PV panels (90% more biomass), and areas under the PV panels were much more water efficient (328% more efficient).
Do solar panels contaminate the soil? Under normal conditions, solar panels are sealed so as not to expose the materials to the surrounding environment. However, occasionally panels have been improperly sealed or otherwise contaminated with toxic chemicals during manufacture. For this reason, only buy solar panels from a reputable manufacturer.
How does solar energy affect soil? One European study showed that large solar arrays affect the physical and chemical characteristics of the soil. In addition, the soil under panels was up to 10 degrees cooler than soil without a cover, producing lower levels of CO2.
Can crops be grown under solar panels?
Agrivoltaic farming is the practice of growing crops under solar panels. Scientific studies show that some crops thrive when grown in this way. Doubling land use in this way could help feed the world’s growing population while also providing sustainable energy.
Why are farmers opposed to solar farms? This dynamic is developing in rural communities across the country as residents respond to a wave of renewable energy developments, with more and more projects. Opponents say that solar energy is a threat to the economy and to people’s health claims that often go unchallenged or are barely challenged at a local level.
What can you plant around solar panels?
Below that are tomatoes, turnips, carrots, squash, beets, lettuce, kale, chard, and peppers. This success was not obvious, and a great leap of faith was required to reap the rewards. “We had to put up our farm as collateral as well as the solar array as collateral to the bank, he said.
Do solar panels affect plants? Solar modules will actually cool crops and vegetation underneath during the day due to shading, and keep them warmer at night.
Can you grow anything under solar panels? Agrivoltaic farming is the practice of growing crops under solar panels. Scientific studies show that some crops thrive when grown in this way. Doubling land use in this way could help feed the world’s growing population while also providing sustainable energy.
Is there toxic runoff from solar panels?
It is important to remember that some types and brands of solar panels are hazardous waste while others are not. The following are some panels that contain or may contain toxic material. CDTe solar panels can be dangerous because of cadmium. Gallium arsenide (GaAs) panels can be dangerous because of arsenic.
Does solar energy produce toxic pollution? Solar energy technologies and power plants do not produce air pollution or greenhouse gases in operation. The use of solar energy can have a positive, indirect effect on the environment when solar energy replaces or reduces the use of other energy sources that have greater effects on the environment.
Is solar runoff more toxic than nuclear waste? â Solar panels create 300 times more toxic waste per unit of energy than nuclear power plants.
How much toxic waste do solar panels produce?
However, the environmental impact of these chemicals is of greater concern. Based on installed capacity and power-related pressure, we can estimate that by 2016, photovoltaics has spread about 11,000 tons of lead and about 800 tons of cadmium.
How toxic is solar panel waste? CDTe solar panels can be dangerous because of cadmium. Gallium arsenide (GaAs) panels can be dangerous because of arsenic. Some older silicon solar panels can be hazardous waste for hexavalent chromium coatings. Newer thin film solar panels contain CIS/CIGS and may be hazardous due to copper and/or selenium.
How much pollution is produced when solar panels are made? Here are the most common sources of energy and the amount of CO2 emitted to produce them: Solar panels produce 50g of CO2 during manufacture. Natural gas produces 117 pounds of CO2 per million British thermal units (MMBtu) during extraction and production. Oil (petroleum) produces 160 pounds of CO2 per MMBtu.
Can solar panels leak toxic chemicals?
Solar panels only contain materials in “solid state” form, just like the electronic components in laptops and smartphones. They do not contain liquids that can leak.â
Can you make solar panels without toxic chemicals? The manufacture of solar panels often contains toxic materials such as cadmium and industrial waste. In a new study, researchers have now developed an eco-friendly method that eliminates the use of toxic cadmium in the production process to produce cost-effective, efficient and eco-friendly solar cells.
What plants grow well under solar panels?
To study these differences, we grow a series of different crops under solar panels. We grow tomatoes, basil, potatoes, beans, squash, and lavender, just to name a few.
Where is the best place to put a solar farm? Top 5 states for Solar in 2021
- 1. California. California ranked as the top state for solar – by a long shot. …
- Texas. Texas, a state known for having its own power grid, is next on the list of best solar states. …
- North Carolina. …
- Florida. …
- Arizona.
What land is best for solar panels?
First, look at your land. If it’s a flat, open spot that’s 20 to 25 acres, your land is a good candidate for an average-sized solar panel farm. You should also know that once a solar developer installs the solar panels, they will have very little effect on the physical condition of your land.
What makes land good for solar panels? Solar developers are looking for flat, clear land, with little to no wetlands, and very little incline (maximum of 5 degrees). YSG has noticed a trend towards single axle tracked units. This is a racking system that will move in one direction (east/west) to produce as much of each solar panel as possible.
How much money does 1 acre of solar panels make? According to 2022 statistics, the average annual profit of a solar farm per acre is between $21,250 and $42,500. The specific profit, of course, depends greatly on the location of the land, the number of solar panels, and the amount of sunshine in the season.
Can you live next to a solar farm?
Electricity from solar panels and transmission to the power grid emits extremely weak electromagnetic fields. Exposure to low-level electromagnetic fields has been extensively studied, and there is no evidence that it is harmful to human health, according to the World Health Organization (WHO).
What are the negative effects of solar farms? The clearing and use of large areas of land for solar energy facilities can adversely affect native vegetation and wildlife in many ways, including loss of habitat; interference with rainfall and drainage; or direct contact causing injury or death.
Do solar farms damage the soil? Aluminum is only released into the soil for a few minutes from a solar system, and it has not been shown to have any negative effects on the earth. While solar systems are safe to have around crops, they are also a great way to help prevent land degradation while still making good use of overworked fields.
Can solar panels be put into deserts?
The desert has an abundant supply of sunlight, making it an ideal place to build a solar power station. However, these plants can have a negative impact on the environment.
Why aren’t solar panels installed in the desert? The harsh desert environment affects the efficiency of solar panels. The dust and sand that accumulates on solar panels interferes with its functionality. As well as being very hot, the fluctuating temperatures during the day and night put rapid thermal cycles on any solar panel materials.
When solar panels share land with cows lettuce and blueberries?
Knowlton’s farm will go one step further: In a third parcel, solar panels will share space with crops so both can thrive. This method is called agrivoltaics – a portmanteau of agriculture and voltaic cells, which transform solar power into electrical power.
Do solar farms harm animals? It can be particularly dangerous for birds. For example, around six thousand birds, including many endangered species, died over the Ivanpah Solar Farm in 2016. Solar farms, especially those that use concentrated sunlight, are extremely dangerous for our avian friends .
What is the dual use of solar and agriculture? Dual use solar, also known as agrivoltaics or collocated solar, is the practice of installing photovoltaic solar panels on farmland in such a way that primary agricultural activities (such as animal grazing and crop/vegetable production) are carried out on the once farmland.
What crops can you grow under solar panels?
To study these differences, we grow a series of different crops under solar panels. We grow tomatoes, basil, potatoes, beans, squash, and lavender, just to name a few.
What can you put under solar panels? At Jack’s Solar Garden in Boulder County, Colorado, owner Byron Kominek has covered 4 of his 24 acres with solar panels. The farm grows a huge variety of crops under them – carrots, kale, tomatoes, garlic, beets, radishes, lettuce, and more.
Do solar farms contaminate the soil? Finally, most solar farms are indeed safe to operate. However, potentially toxic heavy metals and silicon by-products are used in these projects. Damaged units or time can release these contaminants into the environment. Therefore, consider taking soil samples to monitor for potential contaminants.
Why is solar farming not a good use of agricultural land?
Solar farming will change the productivity of the land in the future. Because solar panels only capture 20% of the light for only about 5 hours of the day the rest of that solar energy will pass through to the ground. As a result grasses, broadleaf weeds, and eventually woody shrubs will grow.
Why do people not like the solar farm? They cite reasons that vary from aesthetics that would damage property values to fears about health and safety, and the loss of arable land, farm culture, or wildlife habitat.
Which solar panel is best for agriculture?
What are the best solar panels for agricultural use?
- Trina Vertex with Best Monocrystalline Solar Panel. …
- Hiku Solar Canada has Best Polycrystalline Solar Panel. …
- Renogy 100W Flexible Solar Panel – The Best Thin Film Solar Panel.
How much does agrivoltaics cost? System costs would be approximately $847/kW. The panels are installed at a height of at least 2.5 m from the ground.
What is an agrivoltaic system? Agrivoltaics is the use of land for agriculture and solar photovoltaic energy production. It is also sometimes referred to as agrisolar, dual use solar, low impact solar. Solar grazing is a variation where livestock graze in and around solar panels.
What kind of land do you need for a solar farm?
It must be on level ground, cleared with minimal wetlands and close to three-phase power and a transmission substation. Then there are rows upon rows of solar panels, usually mounted on racking systems, strategically placed to make the most of unused farm or commercial land.
Is my land good for a solar farm? First, look at your land. If it’s a flat, open spot that’s 20 to 25 acres, your land is a good candidate for an average-sized solar panel farm. You should also know that once a solar developer installs the solar panels, they will have very little effect on the physical condition of your land.
How much can a solar farm make per acre? How Much Solar Farm Income Per Acre Per Year Should I Expect? On average, you can expect a return on investment of $21,250-$42,500 per acre annually. However, these figures will vary depending on individual projects.
What area of land is best suited for solar energy?
A study has found that farmland is the most effective area to install solar farms and if only 1 percent of agricultural land was used in this way it would meet the human demand for electricity.
Which location would be best for solar energy? The roof is the best place for solar panels because it receives the most uninterrupted sunlight throughout the day. If your roof is not south facing, you are not out of luck. Some solutions for non-south facing roofs include: Adding larger or larger panels on the east or west side to compensate.
How many acres is needed for a solar farm?
For a typical solar installation, the rule of thumb is that you need about 100 square feet for every 1kW of solar panels. This means that for a 1mW solar photovoltaic power plant, the area required is approximately 2.5 acres or 100,000 square feet.
How much money does a solar farm make per acre? According to 2022 statistics, the average annual profit of a solar farm per acre is between $21,250 and $42,500. The specific profit, of course, depends greatly on the location of the land, the number of solar panels, and the amount of sunshine in the season.
Is 2 acres enough for a solar farm?
A personal solar farm can depend on an acre or two and tends to serve the needs of a single owner. In the case of a large energy user, it could be used to meet all their consumption needs or allow them to reduce their costs by selling power back to their local utility company.
How small can a solar farm be? Utility-scale solar farms can have capacities between 1 MW and 2,000 MW. On the other hand, community solar farms are usually less than 5 MW in size, and it is not uncommon to find some under 100 kW.
How many acres is a good solar farm? The type of solar farm developers want to build varies from one megawatt all the way up to hundreds of megawatts. As a general rule, a 1 MWac (alternating current) solar farm requires 4-7 acres of land. The key variable in that 4-7 acre range is how sunny it is in your area.
How much money can a 5 acre solar farm make?
Is it Lucrative? There are several factors to consider when determining the profit margin of an acre of solar plant, but in general, you can earn anywhere between $21,250-$42,500 per acre annually.
How much energy does a 10 acre solar farm produce? A conservative estimate for the footprint of a solar development is that it takes 10 acres to produce one megawatt (MW) of electricity. This estimate accounts for site development around the solar arrays, including for maintenance and access to the site.
How much acre of land is needed to produce 1 MW of solar energy?
Solar land footprint estimation. A conservative estimate for the footprint of a solar development is that it takes 10 acres to produce one megawatt (MW) of electricity. This estimate accounts for site development around the solar arrays, including for maintenance and access to the site.
How many acres do you need for a 5 MW solar farm? In the case of a large energy user, it could be used to meet all their consumption needs or allow them to reduce their costs by selling power back to their local utility company. On the other hand, utility-scale solar farms require about 30 to 40 acres of land for a 5 MW solar farm.