Project data
Authors Harshavardhan Dinesh
Prannay Malu
Utkarsh Sharma
Uzair Jamil
Joshua M. Pearce
Location Michigan, USA
London, ON
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This literature review is for a project which involves using the same piece of land for setting up a PV farm and performing agriculture/livestock grazing on it. By doing this, the same piece of land can be used to generate electricity and food crops, thus, increasing land use. This setup can prove to be a as it would not only be a steady source of income for farmers but also allow a small area in the vicinity of the PV farm to become self sustaining in terms of electricity.

Initially, this topic would cover the growth of lettuce on a farm having PV panels mounted and the influence of PV panels on the growth pattern of lettuce.

This literature review supported this review article:

This focused article on grape farm potential:

This article discussing the views of farmers on agrivoltaics:

and the views of solar photovoltaic industry persceptives on agrivoltaics:

  • Alexis S. Pascaris, Chelsea Schelly, Laurie Burnham, Joshua M.Pearce. Integrating solar energy with agriculture: Industry perspectives on the market, community, and socio-political dimensions of agrivoltaics Energy Research & Social Science 75, (2021), 102023. https://doi.org/10.1016/j.erss.2021.102023 open access

The life cycle analysis of pasture-based asgrivoltaics for rabbit:

  • Alexis S. Pascaris, Rob Handler, Chelsea Schelly, and Joshua M. Pearce. Life cycle assessment of pasture-based agrivoltaic systems: Emissions and energy use of integrated rabbit production. Cleaner and Responsible Consumption (2021): 100030. https://doi.org/10.1016/j.clrc.2021.100030 academia


Glossary[edit | edit source]

APV - Agrophotovoltaics

AV - Agrivoltaics

AVS - Agrivoltaic Systems

AI - Artificial Intelligence

Amax - Maximum net photosynthesis rate,

BIPV - Building Integrated PV

BG - Bifacial Gain

BF - Bifaciality Factor

CS - Column spacing

CPV - Concentrated PV

CT - Customized Tracking

CT - Constant Tilt

DRAM - Distributed Recycling and Additive Manufacturing

DHI - Diffuse Horizontal Irradiance

DNI - Direct Normal Irradiance

DAS - Day after sowing

FIT - Feed-in Tariff

FS - Full sun

GHI - Global Horizontal Irradiance

GMPV - Ground Mounted PV

IoT - Internet of Things

ICS - Inter-column-spacing

IRS - Inter-row-spacing

LCOE - Levelized cost of electricity

LAI - Leaf Area Index

LCP - Light Compensation Point

LSP - Light Saturation Point

LER - Land Equivalent Ratio

LPF - Light Productivity Factor

OPV - Organic PV

POSCAS - Parametric Open-source Cold Frame Agrivoltaic System

PV - Photovoltaic

PPFD - Photosynthetic photon flux density

POA - Plane of Array

PAR - Photosynthetically Active Radiation

PR - Panel Rows

PSN - Net photosynthesis rate

RS - Row spacing

RT - Reverse Tracking

STC - Standard Test Conditions

SVF - Sky View Factor

ST - Standard Tracking

TT - Tracking Treatment

TRF - Spectral total transmittance factor

WTP - Willingness to Pay

See Also[edit | edit source]


Literature Review Page for "Dual Use of Land for PV farms and agriculture literature review"[edit | edit source]

Selected Papers and Literature[edit | edit source]

Combining solar photovoltaic panels and food crops for optimising land use: Towards new agrivoltaic schemes[1][edit | edit source]

Abstract:

Extracting fuel from biomass was put forth as an alternative energy source to dwindling fossil fuel resources. However, this would involve the widespread use of food crops for producing biomass resulting in food shortages as the existing cultivable land on the planet cannot cope with the demand for crops used for food and biomass at the same time. A solution to this problem is an 'Agrivoltaic' system i.e. a combination of PV panels set up on an existing farmland, thus increasing land use. Simulations have shown an increase in land productivity by 60-70%.

Summary:

  • Optimized solar panel orientation is determined by PVsyst software to ensure maximum amount of radiation is tapped by the panels.
  • Panels are mounted at a certain height over the crops to allow mechanical farming equipment to underneath the panels.
  • Difficult to predict the behavior of crops under the shaded area of the PV panel.
  • Experiments have shown that electricity and crop yield of a 100 hectare farm with an agrovoltaic system in place is greater than a 170 hectare farm having separate production.

Productivity and radiation use efficiency of lettuces grown in the partial shade of photovoltaic panels. European Journal of Agronomy[2][edit | edit source]

Abstract: Converting crop lands into PV farms would aggravate the competition for land between food and energy production. Setting up PV panels on top of crop farms shades a part of the crops. In spite of the shading effect, lettuce yields were higher by improving the Radiation Interception Efficiency. The effect of the shade on the lettuce plantation was a reduction in the number of leaves but and increase in the leaf area. This was the adaptation bought about by lettuce to thrive in the shade. A framework is defined based on the adaptive characteristics of crops that thrive in the shade to optimize agrovoltaic systems.

Summary:

  • Lettuce has the ability to adapt to lower light conditions by increasing its capability to harvest light.
  • Similar experiments were done using cucumber, french beans and durum wheat to study the effect of crop rotation on an agrivoltaic system.
  • Agrovoltaic systems can be optimized by plant breeding and making adjustments to PV panels to find the best way to co-produce electricity and food on the same piece of land.

Solar Farms for livestock[3][edit | edit source]

  • Report released by the BRE and National Solar Center of UK stating that PV farms can be set up on lands reserved for livestock grazing.
  • PV farms gives the farmers an economic boost and at the same time does not affect his existing farming practices.
  • The farmer does not need to cut down on the number of grazing animals nor does he have to adjust the grazing frequency of livestock as 95% of the grazing land is unaffected by the PV panels.
  • A PV farm with an output of 4.2 MW was set up in Axminster, Devon, UK. This farm provides electricity as well as fodder for livestock.

To mix or not to mix: evidences for the unexpected high productivity of new complex agrivoltaic and agroforestry systems[4][edit | edit source]

Abstract: Agrivoltaic schemes are profitable, environment friendly and have high levels of production. These schemes have higher volumes of production due to higher land equivalent ratios. Land equivalent ratio(LER) determines the efficacy of a piece of land. It is calculated by the relative yields of the components on the piece of land in question. LER for an agrovoltaic(AV) systerm was the sum of the relative yield of the crop and the relative yield of electricity by the PV panels.

Summary:

  • LER for a 100 hectare AV farm was in the 1.3-1.6 range. Methods to optimize LER were suggested like having a North-South orientation for the crops.
  • PV panels provide constant shading over crops which affect winter crops more as compared to summer crops due to the sunlight demands of such crops. However, the PV panels acts as a protective measure for the crops in the summer from excessive heat and evaporation.
  • More research is needed on the PV panel density depending on the light demands of various crops.

[http://hrcak.srce.hr/index.php?id_clanak_jezik

26832&show=clanak Assessing the land equivalent ratio (LER) of two corn varieties intercropping at various nitrogen levels in Karaj, Iran.][5]====

Abstract:

LER is the ratio of yield of the individual crop in the intercropped land to the yield of each crop in a monocropped land. LER value of 1.0 indicates the same yield from an intercropped and monocropped land. If LER>1.0 indicates a higher yield from the intercropped land and if LER<1.0, the yield of the monocropped land is higher than that of the intercropped land.

Summary:

  • Experiment was conducted to study the effect of two different varieties of corn on land use efficiency with different nitrogen levels
  • LER's for an intercropped land was observed to be 1.066.
  • At different levels of nitrogen content in the soil, LER's were always greater than zero.

How does a shelter of solar panels influence water flows in a soil–crop system?[6][edit | edit source]

Abstract:

Crops can achieve a higher yield under the fluctuating sunlight of an Agrovoltaic system. Under dry climatic conditions, the climatic conditions below the PV panels suggest that the PV panels help in alleviating the water demand by the crops. Water use efficiency can be increased by selecting crops with a rapid soil covering which contributes to a higher amount of light being captured with decreased soil evaporation.

Summary:

  • Shading due to the PV panels resulted in water savings by 14-29% depending on the level of shading.
  • Water demand reduction was achieved by reduction in incident radiation due to the shading effect.
  • Water use efficiency was found to increase for some varieties of lettuce in the shade

Tradeoffs and Synergies between Biofuel Production and Large Solar Infrastructure in Deserts[7][edit | edit source]

Abstract: The paper discusses the setting up of agrivoltaic schemes in arid regions with limited water resources. It discusses about the use of land between panels for growing biofuel plants like Agave which can thrive in dry and arid climate thanks to its water efficient photosynthesis process. Monte Carlo Approach is adopted to measure the uncertainty amongst the various parameters such as variations in the number of solar modules /ha, module efficiency, overall sugar conversion efficiency for agave and number of agave plants /ha. The limited water resources can be used to clean the PV panels as well as watering the plants by directing the water onto the PV panels which would drain off on the agave plants resulting in efficient usage of limited resources. The Agave plants are used in the production of ethanol fuel.

Summary:

  • Revenues from the solar PV per unit of water used was 100 times greater than that of traditional crops. Combination of solar PV and agave resulted in the highest returns per cubic meter of water used.
  • Competition for land for growing biofuel and food crops is reduced and the agave crops can help in reduction of dust collection on the PV panels.

Renewable energy and food supply: will there be enough land?[8][edit | edit source]

Abstract: Renewable energy schemes such as PV farms require large tracts of land to capture sunlight and produce electricity in large quantities. Ideally, the best place to set up PV farms is on barren land. However, if barren land is not available, PV farms have to be set up on cultivable land used for growing food/cash crops. The land required for energy and food production depends on the demand and supply of that particular area. This paper discusses biomass as a short term renewable energy source and the long term potential of solar energy and their effects on limited land resources.

Summary:

  • The food and electricity yield figures obtained are very sensitive to the changes in the estimated input parameters with respect to land requirements.
  • Two scenarios are considered i.e. rich and poor. In the poor scenario, land requirements fall short when biomass is used as an energy source. In the rich scenario, land requirements for food and energy production are satisfied.
  • Widespread changes are to be incorporated into the existing energy infrastructure to accommodate solar PV systems such as storage batteries that store the energy from the PV panels for use at night or during low light periods.

What is the maximum efficiency with which photosynthesis can convert solar energy into biomass?[9][edit | edit source]

Abstract: This paper examines the efficiency of the photosynthesis process at each step in the conversion of solar radiation into biomass and to understand the factors that limit this efficiency. The efficiency of photosynthesis ranges 4.6% to 6%.

Summary:

  • Plants can tap solar radiation between 400-740 nm which is about 48% of the incident solar radiation on Earth.
  • Reasons for losses in the photosynthesis process include reflection and transmission of solar radiation, photochemical process inefficiency, inability of plants to tap solar radiation wavelengths less than 400nm and greater than 740nm, losses due to photo-respiration.
  • Photosynthesis efficiency can be improved by overcoming the photo respiration losses which is the one of the main limiting factors.

Determination of the optimal tilt angle and orientation for solar photovoltaic arrays[10][edit | edit source]

Abstract: The optimum tilt angle of a PV panel can be determined by maximizing the incident solar radiation on the panel subject to minimization of the variance in the power output. The most accurate solar irradiance figures can be selected from existing data for several PV models. A database is then prepared using the existing data for different tilt angles over different periods of time. Meta-models are produced to co-relate the tilt angle with the solar radiations at different times of the day using the data from the database. An optimization problem is then formulated with an objective to maximize solar irradiation on the panel.

Output energy of a photovoltaic module mounted on a single-axis tracking system[11][edit | edit source]

Abstract: This paper deals with the power output of a PV panel installed in Taiwan at different azimuth's and tilt angles. The gain of a single axis mounted panel was compared with that of a traditionally mounted panel. Simulation results show that the optimal tilt angle for observed radiation is flatter than that from extraterrestrial and global radiation.

Summary:

  • Yearly gains from extraterrestrial, global and observed radiation is 51.4%, 28.5%, 18.7% for a module installed at the yearly optimal tilt angle for over a year. Similarly, the gains for a PV panel mounted at the monthly optimal tilt angle are 45.3%, 25.9% and 17.5% respectively.
  • Conversion efficiency of the PV panel mounted at the yearly optimal angle is 10.2%, 9.2% and 8.3% for extraterrestrial, global and observed solar irradiation.
  • The panels can be mounted either at the optimal yearly tilt angle and changed yearly or at the monthly optimal tilt angle which would be changed on a monthly basis.

&arnumber=4522840&isnumber=4522647 A reconfigurable solar photovoltaic array under shadow conditions][12]

Abstract: This paper proposes a method to reconfiguration scheme to reduce the effect of shading on the PV panels. In this method, a smaller reconfigurable adaptive PV bank is connected to a larger fixed PV bank and the maximum power point(MPP) can be tracked with a single MPP tracker. During non-uniform illumination periods, the number of adaptive solar cells connected to the shaded modules depends on the area of shading. A control algorithm is designed to open and close the switches linking the adaptive and the fixed PV modules. The adaptive reconfiguration is bought about by a switching matrix defined in the control algorithm.

Summary:

  • A matrix of switches is used to connect an adaptive PV array to a larger fixed array with an objective to maximize output power in case of non-uniform illumination.
  • An experimental prototype was built and was used to test said algorithms.
  • This configuration is aimed at avoiding the local MPP of each module and focus on the central MPP of the entire array to maximize power output.

[13]====

Abstract: The power output of a PV system depends on its nominal power, incoming solar radiation and the losses in the system. It also depends on the other factors such as response to low light response, temperature of modules, light spectrum range, deviation from MPP etc. The paper compares theoretical calculations with actual experiments conducted on the field.

Summary:

  • Theoretical calculations compared with experimental data obtained from PV farms set up at Nicosia, Cyprus and Heraklion, Greece
  • Reduction in power output is due to excess photon concentration caused by overheating cells.
  • Part of the experimental data used was involving PV modules made of multicrystalline modules having stable performance characteristics. For example, amorphous Silicon initially have a higher power output, but the output drops after a few months of use.

On morphogenesis of lettuce leaves in relation to light and temperature[14][edit | edit source]

Abstract: The growth of lettuce under different light and temperature conditions was examined with special emphasis on the head of the lettuce. The number of leaves increased as light intensity and temperature increased. Leaf length and width depend on the environmental conditions i.e high light intensity can cause changes in the width of the leaves. The light intensity in turn is responsible for the temperature effect on the leaves. Similarly, variations in the leaf length are more prevalent at low light intensities i.e they elongate faster at lower light intensities. In contrast, light intensity affects the growth rate and duration of the leaf width which are reduced greatly at low light intensities.

Are species shade and drought tolerance reflected in leaf‐level structural and functional differentiation in Northern Hemisphere temperate woody flora?[15][edit | edit source]

Abstract: This paper explores the shade and drought tolerances of the leaves of woody species of fauna found in the Northern Hemisphere. A consolidated database was prepared combining the information regarding leaf traits and species tolerances.

Summary:

  • Plant species with higher drought tolerance were resource conserving species with low nitrogen and photosynthetic capacity, longer life span and higher dry leaf mass.
  • Variation in shade tolerance amongst species did not significantly affect the life of the plant.
  • The shade tolerance of the plant depends upon the type of foliage and also suggests a corelation between the leaf structure and the plant's tolerance to environmental conditions.
  • The ability of plant species to develop tolerance against both, drought and shade is an inherent limitation of the plant species in question.

==== [http://www.jstor.org/stable/2401901?seq

1#page_scan_tab_contents Solar radiation and productivity in tropical ecosystems][16]====

Abstract: This paper attempts to develop an approach relating efficiences of dry matter production to factors that determine growth rates. Tropical fauna examples were used to develop this approach.

Summary:

  • Solar energy storage efficiency is expressed as a product of factors describing the dependence of dry matter production, seasonal variation etc.
  • The limitations used to predict crop growth rates are ignorance about the decrease of leaf diffusion resistance, ignorance about the relation between respiration rates and rate of photosynthesis etc.
  • Another limitation for tropical fauna models is the need to do measurements instead of predictions.

Different methods for separating diffuse and direct components of solar radiation and their application in crop growth models[17][edit | edit source]

Abstract: This paper discusses the effect of diffused solar radiation on the dry matter production of leaves under different climatic conditions. Daily and hourly values of incoming direct and diffuse radiation are compared for incorporation into the simulation of wheat growth models.

Summary:

  • By comparison, accuracy of direct and diffuse components of solar radiation varies with changes in climatic conditions.
  • Final yield calculation results are influenced by the methods used to calculate the incoming radiation.
  • Small errors in calculating solar irradiation affects the final yield figures.

Biofuels: environment, technology and food security.[18][edit | edit source]

Abstract: Dwindling fossil fuel resources have pushed up biofuel production levels significantly over the past 10 years and there has been an impetus towards the intensification towards biofuel use. The life cycle analysis helps in understanding the environmental impacts of biofuel production, land requirements and its impacts on food production. Certain protocols have to be established regarding the social impacts of the biofuel production chain.

Summary:

  • In a nutshell, biofuel production and its supporting social and economic factors depend on the development scale of each country.
  • Biofuel cannot be called as a long term replacement for fossil fuels. It can only act as an intermediate solution.
  • Technological development will allow the transition from simple biofuels like bioethanol, biodiesel to cellulosic ethanol, methanol and bio-hydrogen which would alleviate the impact on food production while using large amounts of raw materials at the same time.
  • The by-product obtained from ethanol production from sugarcane bagasse can be used as fodder for livestock, thus benefiting the livestock industry which in turn would reduce the burden on grazing lands and pastures.
  • Regulatory framework imposes limits on land use and also to improve and safeguard the conditions of personnel involved in the biofuel production industry.

Semi-transparent PV: Thermal performance, power generation, daylight modelling and energy saving potential in a residential application[19][edit | edit source]

Abstract: This paper proposes the use of semi-transparent PV panels for residential applications. The characteristics of semi-transparent PV panels are obtained from field tests which give vital information regarding power output, thermal characteristics etc. Semi-transparent PV panels can also be used for daylighting indoor areas, but the saving from this is not very significant as indoor electricity demands are mostly during nights.

Summary:

  • A semi-transparent PV panel with 50% transmission capacity produces a 5.3% reduction in the heating and cooling energy as compared to a normal PV panel.
  • Net energy savings in terms of total energy consumed would be in the range of 3-8.7% by a semi-transparent PV panel.
  • The inner and outer temperatures of the semi-transparent PV panel were measured during summer and winter seasons. Outside temperatures ranged from 35-75oC in winter and summer respectively. Similarly, inner temperatures ranged from 30-40oC in the summer.
  • In terms of power generation by the PV, the paper assumes poly-crystalline Silicon whose power generation capacity deteriorates after a few months.
  • Optimization of PV panels corresponding to the climate and building characteristics contribute to further savings.

Operating temperature of photovoltaic modules: A survey of pertinent correlations[20][edit | edit source]

Abstract: This paper discusses the operating temperature for the best performance of PV panels.

Summary:

  • The temperature of a PV panel can be co-related to factors such as ambient temperature, wind speed, solar radiation.
  • With respect to the weather, temperature rise of the PV cell is sensitive to wind speed changes and practically independent of atmospheric temperature.
  • Temperature of the PV cell depends strongly on the solar radiation on the PV module.

Light distribution, photosynthetic rate and yield in a Paulownia-wheat intercropping system in China[21][edit | edit source]

Abstract: This paper discusses the effect of shading in a Paulownia-wheat intercropped system and its effect on the wheat yields. Factors such as photosynthetically active radiation(PAR), leaf photosynthesis, canopy leaf area index were measured to study the effects of shading on the wheat yields.

Summary:

  • Shading reduced the PAR by 22%, 44% and 56% during the flowering, grain filling and maturing stage.
  • The amount of PAR intercepted in an intercropped system is less than that in a mono cropped system which in turn reduced the number of grains and the grain dry matter.
  • Wheat yields in the intercropped system was less by 51% than that in the mono cropped system.

An overview of the crop model STICS[22][edit | edit source]

Abstract: STICS was a model developed by INRA in 1996. The model simulates crop growth, water balance and nitrogen balance in the soil with respect to the climatic data obtained on a daily basis. This paper discusses the STICS model concerning interractions between the soil and roots and the relation between crop management and the soil-crop system. In addition to this, specific crop species related data is provided by the experts in this field. The paper also discusses the limitations of this model

Advantages:

  • STICS relies on well established data rather than untested assumptions.
  • Adaptability to different crops.
  • Professionals from various related fields can equally contribute to this model, thus evolving as more and more data is provided, making this model grow.

Agrivoltaics in Ontario Canada: Promise and Policy[edit | edit source]

Pearce, J. M. (2022). Agrivoltaics in Ontario Canada: Promise and Policy. Sustainability, 14(5), 3037.

  • Electricity production in Canada via PV < 1% of total energy generation
  • Ontario accounts for the highest share of PV generation - approx. 94%
  • Agricultural Land Use Regulations restrict solar PV deployment
    • Reason - protect farmland/agricultural land from adverse impacts
  • On the contrary, latest studies manifest dual use of land for both PV development and agriculture (known as Agrivoltaics) is entirely possible and even beneficial:
    • Study conducted on pepper, corn and winter wheat showed financial promise; data of different countries utilized
    • Enhanced agricultural production of the crops (especially shade tolerant crops and leafy vegetables)
    • 1% increased PV output since cooler than conventional PV farms
    • Steady stream of revenue for farmers is ensured through electricity
    • Risk of food price fluctuation is alleviated
  • Ontario's three-tiered land-use policy: 1) agricultural land, 2) specialty crop areas and 3) rural area
    • Defines what types of uses will be allowed on each
    • Uses should either be 1) agricultural, 2) agricultural-related and 3) on-farm diversified
    • Current criteria "on-farm diversified" highly restrictive for agrivoltaics

Future Scope

  • Use Ontario's data (especially solar) for analyzing financial gains when using agrivoltaics for pepper, corn and winter wheat farming
  • Regulations being developed on municipal level to be leveraged for agrivoltaic development
  • Consider Agrivoltaics as an agricultural use or agricultural-related use or use on-farm diversified criteria - detailed criteria discussed in paper
  • For crop rotation, agrivoltaic system may have dynamic designs - requires further research
  • Social acceptance in Ontario - requires further research
  • Four policy areas need to be focused for Agrivoltaics:
    • Research & Development
      • Concentrate Ontario's major markets of crops/vegetables
      • Investigate results for target crops and optimize agrivoltaic systems
      • Test "red greenhouse modules" for field and greenhouse deployment
      • Further research on variety of crops and PV systems designs
    • Education/Public Awareness
      • Citizen science approach to be adopted - devices such as parameteric open-source cold frame agrivoltaic system (POSCAS) to be used
      • Conduct open pilot studies
    • Policy Mechanisms to Support Farmers
      • Explicitly define Agrivoltaics
      • Investigate policy of other countries (Japan, U.S etc.)
      • Introduce Feed-in Tariff (FIT)
      • Study Europe's testing methods and utilize to develop similar standards for Ontario's
      • Align provincial and municipal policies
    • Utilize Agrivoltaics as a Trad Surplus with U.S.
      • International power lines connect Canada to U.S.
      • Many states in U.S. have appalling carbon emission
      • Offset emissions and adverse health impacts with renewable solar power
      • Investigate techno-commercial viability

Limitations

  • Farming methods to be revised - additional cost may incur
  • Limited studies conducted on crop rotation
  • Initial costs of deploying Agrivoltaics is higher than conventional farming or PV systems
    • Sustainable business models required to promote Agrivoltaics adoption
  • Cross-border electricity trade may be called into question on political front
  • Social acceptance in Ontario

Parametric Open Source Cold-Frame Agrivoltaic Systems[edit | edit source]

Pearce, J. M. (2021). Parametric Open Source Cold-Frame Agrivoltaic Systems. Inventions, 6(4), 71.

  • Costs of PV are expected to further decline (approx. 60%)
  • Several technical improvements foreseen in PV development
    • Black silicon
    • Bifacial PV
  • Massive areas required for PV deployment coin land use conflicts
  • The issue can be addressed using Agrivoltaics - dual use of of land for PV electrical generation and agriculture
  • Combinations of different edible plants with PV system variables can be overwhelmingly large
  • Method required for agrivoltaic testing for technology optimization
  • Parametric Open Source Cold-Frame Agrivoltaic System (POSCAS) can be utilized for such testing
    • Replaces the cold frame with semi-transparent PV
  • Frame Design
    • Parametric to adopt for different sizes of PV module
    • Design variables can be controlled via parametric OpenSCAD script
    • 3 printable file generated using distributed recycling and additive manufacturing (DRAM)
  • DRAM to fabricate a POSCAS
    • A wide range of thermopolymers may be used
    • Ensures material flexibility and accessibility
  • Module Design
    • Thin film based thickness of active layer adjusts transparency
    • Crystal silicon technology - spacing adjusts transparency
  • Source of raw material has the highest impact on economics of POSCAS - details discussed in research paper
    • Double POSCAS design also alleviates costs
  • Partially transparent PV with colored designs are also being studied
    • Can increase crop yield
    • May be used in greenhouses
  • POSCAS comparison with cold frame and ground-mounted PV systems indicate economic competitiveness
  • Parametric scripts allows variations in POSCAS framework to be customized on any agricultural crop and agrivoltaic system
  • Considering economic viability, researchers can use DRAM POSCAS for agrivoltaic studies

Future Works:

  • Investigate interplay between PV and nanoparticles responsible for spectral shifting in PV with colored designs for a range of crops
  • Identify ideal PV designs for crops using large no. of POSCAS
  • Include accessories (sensors, fans, cameras etc.) to automate care of plants and soil
  • Sensors can be integrated with Internet of Thigs (IoT)/Artificial Intelligence (AI) for data accumulation
    • Data can subsequently be utilized o optimize crop and PV production
  • Verify impact of reflection of solar energy from crops on bifacial PV modules

Crop-specific Optimization of Bifacial PV Arrays for Agrivoltaic Food-Energy Production: The Light-Productivity-Factor Approach[edit | edit source]

Riaz, M. H., Imran, H., Alam, H., Alam, M. A., & Butt, N. Z. (2022). Crop-Specific Optimization of Bifacial PV Arrays for Agrivoltaic Food-Energy Production: The Light-Productivity-Factor Approach. IEEE Journal of Photovoltaics.

  • Agrivoltaics systems installation for improved sunlight sharing between PV arrays and crops
    • Height of PV modules kept between 4 - 7 m above crops
    • Low density - p/h ratio 2 to 3 times of standard PV
  • Paper introduces Light Productivity Factor (LPF) - factor that determines efficacy of light sharing between PV modules and crops
    • For PV only - LPF=1; with Agrivoltaics methodology 1 < LPF > 2
    • Used lettuce, turnip and corn
  • Land Equivalent Ratio (LER) - factor that provides food-energy performance
    • Uses crop yield and electrical output
  • Crop yield is directly proportional to useful photosynthetically active radiation (PAR)
  • Crops have a threshold PAR above which the process of photosynthesis saturates
  • Custom tracking; combination of standard and reverse tacking maximizes PAR requirement
  • Results indicate:
    • For shade tolerant crops, full density PV arrays may be utilized
    • For shade sensitive crops. reduced density PV arrays may be utilized
    • E/W faced vertical PV orientation - preferable fixed tilt scheme
      • Benefits: Low elevation mounting, ease of operation of farm machinery and reduced soil loss

Integration of bifacial photovoltaics in agrivoltaic systems: A synergistic design approach[edit | edit source]

Katsikogiannis, O. A., Ziar, H., & Isabella, O. (2022). Integration of bifacial photovoltaics in agrivoltaic systems: A synergistic design approach. Applied Energy, 309, 118475.

Objective - Devise a multi-scale modelling approach and ascertain optimal topology for APV

  • Idea of APV first coined in 1981
  • Conventional topologies are harmful for crop production
  • Maximum crop productivity (or photosynthesis process) achieved at light saturation point (LSP) - exceeding irradiance alleviates productivity
  • Crops can be classified as C3 & C4 based on carbon assimilation - C3 preferable for APV systems as they saturate at low photosynthetically active radiation (PAR)
  • Plant productivity increased by 5% by using diffusion cover - (cucumbers 8%, roses 10% & tomatoes 8-11%)
  • PV array may reduce soil temperature, crop temperature during noon positively impacting crop productivity
  • Results indicate:
    • Increased irradiance and bifacial gain (BG) by elevated height of PV array; however, main advantage is ease of operation of agricultural machinery
    • Increasing row spacing (RS) reduced electrical output, though, it increased ground irradiation and bifacial gain (BG)
    • South-west orientation augments light penetration in morning while provides shading in noon
    • South facing topologies conducive for cultivation during summer and shade tolerant crops
    • E-W vertical for permanent crops and during winter

Improving Productivity of Cropland through Agrivoltaics[edit | edit source]

Nassar, A., Perez-Wurfl, I., Roemer, C., & Hameiri, Z. Improving Productivity of Cropland through Agrivoltaics.

Objective - Review existing literature of Agrivoltaics and ascertain its applicability in Australia

  • Land equivalent ratio (LER) - parameter used for this study
  • Electrical output of PV system modelled via System Advisory Model
  • Crops (lettuce and silverbeet) grown without shading and under shade (using black tarps) for the study - solar panels not installed
  • Yield produced in Agrivoltaics setting: 72% of lettuce yield compared with traditional farms; 60% of silverbeet yield compared with traditional farms (based on fresh mass)
  • Reduced crop yield most probably due to increased shading

Solar Sharing for Both Food and Clean Energy Production: Performance of Agrivoltaic Systems for Corn, A Typical Shade-Intolerant Crop[edit | edit source]

Sekiyama, T., & Nagashima, A. (2019). Solar sharing for both food and clean energy production: performance of agrivoltaic systems for corn, a typical shade-intolerant crop. Environments, 6(6), 65.

  • Agrivoltaics may have beneficial application for shade-tolerant crops as per past researches
    • Shade tolerance - ability of crops to sustain low levels of light
    • Stilt-mounted agrivoltaics alleviate trade off between crop production and energy generation
    • First agrivoltaic farm experimentation conducted in France with lettuce - research depicted no major impact on lettuce yield
    • Experimentation on durum wheat showed increase (35-72%) in yield
    • 30% increased economic value by employing agrivoltaics on shade-tolerant crops
  • Research conducted on corn in three configurations: traditional farming without solar panel installation (control), low module and high module density
    • PV modules used self-cleaning glass
    • Identical soil, fertilizer and water used
    • Organic farming adopted
    • No pesticides used
    • Feed-in-tariff of 48 yen per kWh
  • Corn yield increased by 5.6% for low density configuration compared with control configuration; total revenue increase 4.7 times larger than control configuration
  • Corn yield reduced by 3.6% for high density configuration compared with control configuration; total revenue increase 8.3 times larger than control configuration
  • High density configuration produced approx. twice electrical output than low density configuration
  • Both low and high density configuration are economically beneficial even if the tariff is reduced to 8 yen per kWh
  • Reasons for high crop yield:
    • Increasing light beyond light saturation point
    • Too high light exposure
    • Reduced water evaporation due to installed PV panels

Future Works:

  • Extend work to shade intolerant crops (watermelon, tomato cucumber, pumpkin, cabbage, turnip & rice)
    • Especially incorporating stilt-mounted configuration
  • Verify results with large sample size
  • Carry out further financial feasibility studies
  • Improved PV designs for enhanced electrical output and agricultural yield

Crop production in partial shade of solar photovoltaic panels on trackers[edit | edit source]

Hudelson, T., & Lieth, J. H. (2021, June). Crop production in partial shade of solar photovoltaic panels on trackers. In AIP Conference Proceedings (Vol. 2361, No. 1, p. 080001). AIP Publishing LLC.

Objective: Ascertain economic viability of crop production under tracking-based PV solar system

  • With PV tracking system, 7 acres land may be required for 1 MW of electrical output
  • Crops experimented: kale, chard, broccoli, spinach, peppers and tomatoes
  • PV panels adopted with tracking system
    • Panel rows (PR) 1 to 7 - crops grown under solar panels
    • Panel row (PR) 8 - traditional crop farming without solar panels (control configuration)
  • Average ambient air temperature increased in morning and reduced in afternoon when compared with control (no panel) configuration
  • No substantial difference in relative humidity in any PR configuration (with or without solar panels)

Results:

  • Biomass accumulated as a function of photosynthetically active radiation (PAR) - varied for different crop type
  • Yield of kale reduced by 23% when compared with control configuration - similar yield production between 55% and 85% of full sun PAR level
  • Yield of chard similar to control when PAR was 85% of full sun values - slight less yield when PAR level was 55% and 62% of full sun numbers
  • Yield of broccoli attainable with at least 85% of full sun PAR - intolerant to high shading
  • Yield of pepper attainable above 55% of full sun PAR - however, quantity will be reduced. For considerable yield, PAR to be greater than 85% of full sun
  • Yield of tomato attainable above 55% of full sun PAR - can tolerate slight shading
  • Yield of spinach extremely sensitive to PAR
  • Maximum daily temperatures 3oC cooler under panel during summer while 2oC warmer during spring
  • For a 24-hour period - temperatures remained warmer in the morning and cooler in the afternoon when compared with full-sun conditions
  • Kale, chard and tomatoes can be cultivated as long as 55% of full-sun irradiance can be attained with PV arrays
  • Cultivation of spinach not advisable considering its high reliance on on solar irradiance

Efficiency Improvement of Ground-Mounted Solar Power Generation in Agrivoltaic System by Cultivation of Bok Choy (Brassica rapa subsp. chinensis L.) Under the Panels[edit | edit source]

Kumpanalaisatit, M., Setthapun, W., Sintuya, H., & Jansri, S. N. (2022). Efficiency Improvement of Ground-Mounted Solar Power Generation in Agrivoltaic System by Cultivation of Bok Choy (Brassica rapa subsp. chinensis L.) Under the Panels. International Journal of Renewable Energy Development, 11(1).

Objective: Investigate improvement in efficiency of PV electrical generation by cultivation of crops beneath the PV modules

  • Study conducted on 25kW power plant using amorphous PV modules; crop selected: bok choy since it can grow well under shade
  • Average solar intensity recorded = 569W/m2
  • Temperature of solar panels was 0.18oC less with crop production beneath when compared with control configuration
  • Crops below solar panel may result in reduced module temperature and higher electrical power output (0.09%)
  • Crop production without solar panels was higher when compared with crop yield with solar panels

Future Works:

  • More crops to be investigated which are favorable for growth under PVs for instance lettuce, spinach, celery, spring onion, ginger, galangal, sweet potato, carrots and chili

Yield Optimization Through Control Strategies in Tracked Agrivoltaic Systems[edit | edit source]

Gfüllner, L., Muller, O., Meier-Grüll, M., Jedmowski, C., & Berwind, M. Yield Optimization Through Control Strategies in Tracked Agrivoltaic Systems.

Objective: To optimize light distribution for gaining maximum crop yield and electrical output via unique solar tracking systems

  • Three strategies were studied:
    • Focus on PV generation - horizontal single axis east west tracking system
    • Focus on plant growth
    • Focus on dual-use (crop production and PV electrical generation)
  • Crop selected: Potatoes; experimental setup was simulation based
  • Results indicate that crop yields are higher in an agrivoltaic system - reason could be increased soil moisture levels

Future Works:

  • Develop a crop model based on hourly timesteps
  • Improved weather files to better investigate impact on crop yields
  • Investigate water resource as a function of optimized tracking system

Comparison of Yield and Yield Components of Several Crops Grown under Agro-Photovoltaic System in Korea[edit | edit source]

Jo, H., Asekova, S., Bayat, M. A., Ali, L., Song, J. T., Ha, Y. S., ... & Lee, J. D. (2022). Comparison of Yield and Yield Components of Several Crops Grown under Agro-Photovoltaic System in Korea. Agriculture, 12(5), 619.

Objective: Investigate crop yields with agrivoltaic systems and compare with control configuration

  • Korea - one of the five top-most importers of fossil fuels
  • Crops experimented: Rice, onion, garlic, rye, soybean, adzuki bean, monocropping corn and mixed planting of corn with soybean
  • Experiment conducted with dummy solar panels
  • Advantages of cultivating crops under PV panels:
    • Effective water/rain distribution and protection against climatic uncertainty
    • Reduced evapotranspiration, soil and crop temperature
    • Increased carbon uptake and water use, land productivity

Results:

  • Yield of rice: Reduced by 18.7% and 8.9% in 2018 and 2019 when compared with open field
  • Yield of soybean: No difference in 2019 while significantly higher in 2020 for open field
  • Yield of adzuki bean: No difference in 2019 while higher in 2020 for open field
  • Yield of garlic and onion: Reduced by 18.7% and 14.6% in 2018-19 and 2019-20 when compared with open field
  • Yield of rye: No significant difference between APV system and open field
  • Yield of corn: No significant difference between APV system and open field
  • Yield of mixed planting of corn with soybean: Reduced when compared with open field
  • Yield of onion: Reduced by 14.4% when compared with open field
  • Yield of garlic: Reduced by 18.7% when compared with open field
  • Conclusive results deduced for corn, rye and rice - for remaining crops, results were inconclusive

Future Works:

  • Research on crop yield for soybean and adzuki bean under APV systems
  • Determine various crop's critical sunlight period requirements to understand their physiological mechanisms
  • Further trials for rice, soybean, adzuki bean, onion and garlic under APV system

Effects of Agrivoltaics (Photovoltaic Power Generation Facilities on Farmland) on Growing Condition and Yield of Komatsuna, Mizuna, Kabu, and Spinach[edit | edit source]

KIRIMURA, M., TAKESHITA, S., MATSUO, M., ZUSHI, K., GEJIMA, Y., HONSHO, C., ... & NISHIOKA, K. (2022). Effects of Agrivoltaics (Photovoltaic Power Generation Facilities on Farmland) on Growing Condition and Yield of Komatsuna, Mizuna, Kabu, and Spinach. Environmental Control in Biology, 60(2), 117-127.

Objective: Investigate crop yields with agrivoltaic systems

  • Crops experimented: Komatsuna, kabu, mizuna and spinach
  • PV panels covered 62% of ground area farm - constant tilt (CT) tracking treatment (TT) as well as control configuration was adopted for study
    • Tracking treatment - single axis
  • Electrical generation income calculated at 37 yen/kWh

Results:

  • Solar radiations transmitted below PV panels
    • TT - 24% of open field radiations
    • CT - 39% of open field radiations
  • Growth rate of komatsuna, mizuna and kabu slower under PV panels - no difference in yields between CT & TT configurations
  • Significant reduction in yield of spinach - not suitable for growth under conditions of alleviated solar radiations
  • Yield, solar radiation, light intensity and air & soil temperature were lower under PV panels
  • Results indicate that
    • Mizuna and kabu are suitable for cultivation in winter season
    • Komatsuna most suitable for growth under PV panels
    • TT conditions suitable for komatsuna and kabu while CT for mizuna
  • Extended cultivation times could result in sufficient yields

Global energy assessment of the potential of photovoltaics for greenhouse farming[edit | edit source]

  • World temperatures may increase to 3.2oC till 2100AD
  • Fossil fuels are responsible for 3/4th of greenhouse gases (GHGs)
  • Estimated world population by 2050 - 9 billion
    • 70% increase in production of food will be needed
  • Energy demands could be met if only 1% of agricultural land is converted to APV
  • The paper discusses a novel Agrivoltaic Model - output: electricity generated and crop photosynthesis rate with regards to Agrivoltaics transparency
    • Three sub models - solar radiation, PV and crop
      • Outputs - PV model: energy harvested with time; crop model: CO2 abosrbed during photosynthesis over time;
  • Experimental locations: El Ejido (Spain), Pachino (Italy), Antalya (Turkey) and Vicente Guerrero (Mexico).
  • PV technology adopted semi-transparent c-Si technology based on opaque cells
    • Reason: High efficiency & reliability
  • Crops selected: 15 species from 5 different families, i.e. Cucurbitaceae, Fabaceae, Solanacae, Poaceae, Rosaceae
  • TRF - Gobal transparency of PV module; TRF value is 0 for fully opaque and 1 for fully transparent
    • Increase TRF - PV energy alleviates while crop performance augments
  • Optimum PV system considered for the application - transparency set as such that net photosynthesis rate (PSN) does not reduce more than 10%
  • Lower photosynthetic photon flux density (PPFD) at which maximum photosynthesis rate (Amax) is achieved, lower will be the TRF resulting in higher PV energy without adversely affecting the crops
  • Solanacae, followed by the Rosaceae and the Curcubitaceae - most suitable families for APV applications in greenhouses

Effects of different photovoltaic shading levels on kiwifruit growth, yield and water productivity under “agrivoltaic” system in Southwest China[edit | edit source]

Jiang, S., Tang, D., Zhao, L., Liang, C., Cui, N., Gong, D., ... & Peng, Y. (2022). Effects of different photovoltaic shading levels on kiwifruit growth, yield and water productivity under “agrivoltaic” system in Southwest China. Agricultural Water Management, 269, 107675.

Objective: Investigate impact of different shading levels on kiwifruit

  • Previous studies indicated no adverse impact of Agrivoltaic setup on tomato and cucumber
  • Experiment conducted using three (03) different densities (19%, 30.4%, 38%) of translucent PV - same compared with control configuration
  • Kiwifruit used for experimentation due to its compatibility with shading for growth
    • Kiwifruit plant is capable to acclimatize to shaded environment
  • Results indicate
    • Solar radiation reduced as compared to control configuration - percentage of reduction increased with increased shading
    • No impact of shading on temperature
    • Relative humidity augmented with increased shading

Leaf transpiration rate, accumulated transpiration, soil evaporation, photosynthetic rate and water use efficiency reduced with increased shading

    • Higher densities (30.4% & 38%) had a significant adverse impact on kiwifruit yield and volume
    • With 19% of translucent PV panels, kiwifruit yield slightly reduced - configuration suitable for kiwifruit growth with Agrivoltaic setup as no major impact on yield

Consumer Study of Agrivoltaics Food Products Including Tomato, Basil, Potato, Bean, and Squash[edit | edit source]

Rogers, M. (2022). Consumer Study of Agrivoltaics Food Products Including Tomato, Basil, Potato, Bean, and Squash (Doctoral dissertation, The University of Arizona).

  • Not much reasearch on senorial charateristics and consumer acceptability of AV based crops
  • For AV to be successful, it must be sustainable (economically, socially and environmentally) - the study explores all three aspects
    • It analysed users' responses to AV configuration and control configuration to gauge any differences/preferences for the crops

Objective:

  • To carry out study of AV crops (tomatoes, basil, beans, potatoes and squash) to ascertain any impact of growth conditions on sensory charatecteristics
  • Testing techniques employed
    • Triangle test - determine perceptible difference between samples grown in different growth conditions
    • Paired comparison test - determine difference in sensory attributes between AV and control growth configuration
    • Paired preference test - determine preference of changed/modified product vs established product
    • 5-point ordinal Likert scale
    • Multinomial logistic regression and logistic regression

Economic Sustainability:

  • AV have no major history of profitability
  • Installation and maintenance costs are high
  • Subsidies and amneties for AV could promote the technology
  • Fair wages for farm workers to be ensured or its growth

Social Sustainability:

  • Producers/suppliers of AV can promoted social sustainability of the technology by ensuring fair wages to workers, healthcare benefits, safe working environment, fair pricing and preserving cultural heritage
  • Consumers can do the same by reducing waste, eating locally and seasonally
  • AV provides safer environment to workers by protecting them from excessive heat
  • Electrical risk is associated with AV - threat to human and animal life
  • Local workforce and involvement to be enhanced to develop AV technology
  • Diversification of workforce (gender, races etc.) is also imperative to promote AV technology

Environmental Sustainability:

  • Potential environmental issues associated with AV: soil erosion, PV waste and pollinator pattern
  • Rainwater collection system can reduce the risk of soil erosion
  • Proper soil selection is also imperative to protect cropland beneath PV
  • To reduce PV waste, it can be recycled

Conclusion:

  • No major differences/preferences were reported by the tasters between AV-based crops and control grown crop
    • Fruits more likely to be identified as different than vegetables
    • Only beans were preceived as different from the tests
  • Individuals were also inclined to pay more for AV based crops

Future Works

  • Carry out similar research at other geographical locations with variety of crops
  • Reward participants of the study
  • Record data at different times of the season
  • Consider participants prior knowledge and perceptions about solar industry for better understanding of their responses and their utilization in the study
  • Larger sample size for similar research

Page data
Part of 5490-16
Type Project, Literature review
Keywords most literature reviews, photovoltaics, agrivoltaics, energy
SDG Sustainable Development Goals SDG07 Affordable and clean energy
Authors Harshavardhan Dinesh, Uzair Jamil, Prannay Malu
Published 2015
License CC-BY-SA-4.0
Impact Number of views to this page and its redirects. Updated once a month. Views by admins and bots are not counted. Multiple views during the same session are counted as one. 9,516
Issues Automatically detected page issues. Click on them to find out more. They may take some minutes to disappear after you fix them. No main image, Lists nested too deep
  1. Dupraz, C., Marrou, H., Talbot, G., Dufour, L., Nogier, A., & Ferard, Y. (2011). Renewable Energy, 36(10), 2725-2732.
  2. Marrou, H., Wéry, J., Dufour, L., & Dupraz, C. (2013).44, 54-66.
  3. PVMagazine Article
  4. Dupraz, C.
  5. Dariush, M., Ahad, M., & Meysam, O. (2006). Journal of Central European Agriculture, 7(2), 359-364.
  6. Marrou, H., Dufour, L., & Wery, J. (2013).European Journal of Agronomy, 50, 38-51.
  7. Sujith Ravi, David B. Lobell, and Christopher B. Field. Environmental Science & Technology 2014 48 (5), 3021-3030
  8. Nonhebel, S. (2005). Renewable and sustainable energy reviews, 9(2), 191-201.
  9. Zhu, X. G., Long, S. P., & Ort, D. R. (2008). Current opinion in biotechnology, 19(2), 153-159.
  10. Mehleri, E. D., Zervas, P. L., Sarimveis, H., Palyvos, J. A., & Markatos, N. C. (2010). Renewable Energy, 35(11), 2468-2475.
  11. Chang, T. P. (2009). Applied energy, 86(10), 2071-2078.
  12. Dzung Nguyen; Lehman, B., " Applied Power Electronics Conference and Exposition, 2008. APEC 2008. Twenty-Third Annual IEEE , vol., no., pp.980,986, 24-28 Feb. 2008 doi: 10.1109/APEC.2008.4522840
  13. Mavromatakis, F., Makrides, G., Georghiou, G., Pothrakis, A., Franghiadakis, Y., Drakakis, E., & Koudoumas, E. (2010).Renewable Energy, 35(7), 1387-1390.
  14. Bensink, J. (1971). Vernman and Zonen.
  15. Hallik, L., Niinemets, Ü., & Wright, I. J. (2009). . New Phytologist, 184(1), 257-274.
  16. Monteith, J. L. (1972). Journal of applied ecology, 747-766.
  17. Bindi, M., Miglietta, F., Zipoli, G., 1992. Clim. Res. 2, 47–54.
  18. Escobar, J. C., Lora, E. S., Venturini, O. J., Yáñez, E. E., Castillo, E. F., & Almazan, O. (2009). Renewable and sustainable energy reviews, 13(6), 1275-1287
  19. Wong, P. W., Shimoda, Y., Nonaka, M., Inoue, M., & Mizuno, M. (2008). Renewable energy, 33(5), 1024-1036.
  20. Skoplaki, E., & Palyvos, J. A. (2009). Renewable Energy, 34(1), 23-29.
  21. Li, F., Meng, P., Fu, D., & Wang, B. (2008). Agroforestry Systems, 74(2), 163-172.
  22. Brisson, N., Gary, C., Justes, E., Roche, R., Mary, B., Ripoche, D., ... & Sinoquet, H. (2003). European Journal of agronomy, 18(3), 309-332.
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