This study aims to discover how lettuce and potato crops are impacted by the shade of photovoltaic (PV) panels. Four scenarios are considered, with varying parameters such as latitude, azimuth, slope, and row distance between PV modules. The results reveal a significant potential for growing potatoes under PV modules. However, lettuce faces difficulties due to its high requirement for solar intensity (PAR), making it less adaptable to shade. The findings of this study indicate that crops like potatoes, which have a lower requirement for PAR, can be successfully cultivated in conjunction with PV systems.
Tag Archive for: solar-suitable crops
In this case study, researchers quantified the increase of land productivity derived from the integration of an experimental vertical farm (VF) for baby leaf lettuce inside a commercial photovoltaic greenhouse. The mixed system increased the lettuce yield by 13 times compared to a non-VF PV greenhouse and the average LER was 1.31. However, only 12 %
of the energy consumption was covered by the photovoltaic energy system.
The objective of this thesis work is to evaluate the introduction of agrivoltaics in Italy through the study of the effect of the presence of photovoltaic panels on the final yield of potatoes in Ferrara, Italy. The findings of this preliminary study indicate that agrivoltaic systems should be designed while taking into account the need to ensure a minimum level of incident radiation at least in the first two months of cultivation, to avoid an inter-row production drop. Furthermore, photovoltaic panels are not responsible for the absolute low yield in years with unfavorable weather conditions, such as cold years; on the contrary, they may mitigate the damages to the crop by creating an underneath microclimate and the resulting higher temperature, which however is a hypothesis to be verified in more detail in future studies.
This article presents a comparison of changes in vine growth and fruit characteristics due to the installation of solar panels in the vineyard. Researchers found that the development of vines and fruits was not significantly different, and that the post-harvest fruit showed no difference in granules, fruit discharge, sugar content, or pericarp color.
This study addresses the interplay between radiation transmission, crop development and irrigation needs of corn cropping in field conditions, by the description of crop development dynamics, distinguishing between fixed and dynamic panels. Researchers showed that maize crop responded to both independent and combined stresses (shade and water deficit), with a significant decrease in leaf area index, total dry matter and grain yield. Concerning water use, we showed the potential of AV to reduce irrigation inputs (by up to 19–47% compared to unshaded plots) via reduced soil water depletion and reference evapotranspiration.
This two-year study aimed to analyze whether intermittent shading produced by panels placed over grapevines can delay grape ripening to counter the impact of global warning on phenology. Researchers concluded that intermittent shading produced by panels can shift ripening into a cooler period compared to unshaded plants. They also state that shading intensity and duration should be adapted to evaporative and soil water conditions to benefit from the phenological delay caused by panels, without altering production in the long term.
Results of Agrisolar Soybean Pilot Project Revealed by PV Developer
“French solar developer TSE, in association with Alliance BFC, has unveiled the initial results of a pilot study in France on how solar panels can affect soybean growth. The teams observed solid vegetative growth of the soybeans, with normal flowering, fertilization, and physiological maturation. The six varieties tested presented a diversity of yields: up to 25% difference in yield under the canopy and 19% on the control field.” – PV Magazine
Oregon Research Studies Use of Vertical PV for Crop Production
“There are many different ways to install agrivoltaic arrays. One common method is to raise the array to leave space for farming equipment or livestock to move freely below. Another trending design is to orient the PV arrays vertically, leaving wide open spaces in between the array rows.
The paper found that an area about the size of Maryland would be needed if agrivoltaics were to meet 20% of U.S. electricity generation. That’s about 13,000 square miles, or 1% of current U.S. farmland. At a global scale, it is estimated that 1% of all farmlands could produce the world’s energy needs if converted to solar PV.” – PV Magazine
Research Shows Translucent Solar Panels Optimize Crop and Solar Harvest
“Associate professor Majdi Abou Najm from the Univ. of California, Davis, tested organic solar panels made from translucent material that absorb the blue light to generate electricity, but allow the red light with its longer wavelengths to pass through to the crops below.
At the UC Davis Agricultural Experiment Station, Abou Najm and his team planted three different plots of processing tomatoes, a common central valley California crop, under a canopy of selective red light, another of selective blue, and a third uncovered plot.
GNN has reported before on the recent phenomenon of ‘agrivoltaics,’ a practice of growing shade tolerant crops under solar panel arrays. The shade protects the crops from heat stress, while the plants’ transpiration humidifies the air beneath the panels, cooling them down and increasing their electricity output.” – Good News Network
By Asaf Maman and Avi Elkayam, Trigo Solar
Declining precipitation levels and the associated reduction in arable land can negatively impact rural communities and pose a threat to food security. While utility-scale solar projects reduce greenhouse gas emissions, they can also encroach on arable lands and reduce the yield of rainfed crops. Wheat, barley, soy, corn, and other grains are cultivated in rainfed fields that are vital to food security. As precipitation levels decline and desertification spreads, arable land and farms that produce these crops are in peril.
As solar energy is employed in the conversion from fossil fuels to renewable energy, hundreds of thousands of square miles of land will include solar development. According to the National Renewable Energy Laboratory, there will be roughly 22,000 square miles of solar in the U.S. by 2035i. It is important to understand that the actual land for solar development must be adjacent to grid or to power demand centers. The growing competition between farming, suburban development, and solar development highlights the potential for agrivoltaics.
Agri-PV is a solution to this issue. It can significantly improve the cultivation of staple foods that substantially affect global food security by cracking the code and untying the water-land knot. By increasing the amount of water available for rainfed crops, we can increase the amount of arable land and avail a portion of it for sustainable solar development.
In a series of field-controlled winter wheat experiments, Trigo has discovered an almost linear correlation between the amount of water supplied to cultivated area and the quantity of stem biomass and nutritional value. Based on these findings, Trigo designed an east-west solar array formation and solar table structure to both collect and regulate rainwater for redistribution into a cultivated row below. By increasing the rain capture area from both structures, enclosing, and effectively directing the rain, we managed to control the amount of water and increase it, countering the effects of declining precipitation over years.
North-south solar array over winter wheat. Photo: Trigo Solar
Design schematic. Source: Trigo Solar
This design is focused on economic and efficient deployment of solar arrays that improve rain collection and redistribute water to boost crops growth, counter drought effects, and revive agricultural operations.
Rainwater catchment design schedmatic. Source: Trigo Solar
Benefits to this design include:
- Maintaining the same yields from smaller cultivated surface area requires more limited farming operations and lower expenses, which can increase farm profitability.
- Capturing more water and channeling it smartly reduces the risk of drought and the associated annual volatility and provides the farm with a drought shield.
- Increased ground wetness, root growth, and wind shield from the solar rows reduces the erosion and carry away of the upper soil layer, which create irreversible damage to farms.
- Preserved land under the Trigo structure can be used for future land reserve and land rotation.
- The steady income from solar power generation can support farm economics and mitigate farming financial risks.
- The availability of cheap, local, green power can further support many of the farm operations expected to undergo electrification in the coming decade.
- The existence of a water-distribution and cheap-power system changes the economics of farming, potentially allowing the cultivation of second seasonal crop during the dry season.
These benefits have the potential to create more win-win opportunities for effective cooperation between the agricultural and sustainable energy sectors.
Trigo will continue its experiments to validate the benefits for major U.S. staple crops at U.S. farms to share the knowledge and promote sustainable mass Agri-PV development.
Win for America’s Farmers: Harvesting Solar Energy
“America’s solar industry has boomed in recent years, and is slated for a big boost from the Democrats’ recently passed climate bill. Yet solar still only accounts for about 3 percent of electricity flowing into America’s grid—less than one-seventh the share from coal. If we want to phase out fossil fuels and accommodate an electric vehicle revolution, the sun’s contribution has to rise dramatically—and fast. But where to put all the panles?
The best places for solar installations, according to a 2019 study from the University of Utah and Oregon State, tend to be the areas where we already grow our food. That’s because, just like sun-loving tomato plants that fare poorly when the mercury creeps north of 85 °F, photovoltaic (PV) panels lose their efficiency at higher temperatures. But that doesn’t mean we have to starve ourselves to keep lights on and cars humming. By elevating solar panels far enough above the ground so people, plants, and animals can operate underneath, we can “essentially harvest the sun twice,” says University of Arizona researcher Greg Barron-Gafford. Enough sunlight to grow crops gets past the panels, which also act as a shield against extreme heat, drought, and storms.” – Mother Jones
5 Signs the US Agrisolar Revolution has Begun
“An upswell of opposition to large-scale solar power plants on farms took shape in the U.S. last spring, partly fueled by conspiracy theories about climate change. Nevertheless, farmland is attractive to solar developers. Now they have a new support system on their side, in the form of agrivoltaics.” – Triplepundit.com
Solar Energy Corporation of India Issues Tender to Install Agrisolar Pumps
“New Delhi: The Solar Energy Corporation of India (SECI) on Monday issued a tender for setting up agricultural solar pumps in selected states pan-India under component-B of the PM-KUSUM scheme of the renewable energy ministry.
‘Individual farmers will be supported to install standalone solar agriculture pumps of capacity up to 7.5 HP for replacement of existing diesel agriculture pumps and irrigation systems in off-grid areas, where grid supply is not available. Installation of new pumps will be permitted under this scheme except in dark zone areas,’ said the SECI tender document.” – Energyworld.com
UC Davis Study Shows Harvesting Various Light Spectra Benefits Agrisolar
“Scientists from the University of California, Davis, are investigating how to better harvest the sun — and its optimal light spectrum — to make agrivoltaic systems more efficient in arid agricultural regions like California.
Their study, published in Earth’s Future, a journal of the American Geophysical Union, found that the red part of the light spectrum is more efficient for growing plants, while the blue part of the spectrum is better used for solar production.” UCDavis.com
Massachusetts Sees Increase in Agrisolar Incentives
“A Massachusetts incentive program for projects that blend solar energy and agricultural production shows signs of finally gaining momentum after a slow rollout that has at times frustrated solar developers and farmers alike.
In 2018, Massachusetts became the first state to offer financial incentives for “dual-use” or “agrivoltaic” solar projects built above active agricultural land. Since the launch, however, just three projects have gotten up and running. Another eight have qualified for the incentive but not yet been built.” – Energynews.com