• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 4
  • 1
  • Tagged with
  • 6
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Modeling Irradiance Distributions in Agrivoltaic Systems

Allison Perna (7486406) 14 January 2021 (has links)
<p>Land use constraints have motivated investigation into the spatial coexistence of solar photovoltaic electricity production and agricultural production. Previous work suggests that agriculture-photovoltaic (agrivoltaic) systems either decrease crop yield or are limited to shade-tolerant crops. Existing experimental work has also emphasized fixed south-facing configurations with traditional commercial panel shapes, and modeling work is sparse. In this work, the effects of different photovoltaic array configurations and panel designs on field insolation spatial and temporal variation are explored in detail to determine photovoltaic design routes that may increase expected crop yield in agrivoltaic systems. It is found that photovoltaic row orientation is the most influential factor on insolation homogeneity due to shadow migration paths. Additionally, it is shown that utilization of mini-modules in patterned panel designs may create more optimal conditions for plant growth while using the same area of PV, thus improving the land efficiency ratio of the agrivoltaic system. Different solar tracking algorithms are explored to optimize the trade-off between electricity production and expected crop growth. The feasibility of select agrivoltaic systems is explored for multiple U.S. locations. This thesis concludes with recommendations for photovoltaic system designs corresponding with specific crop growth considerations.<br></p>
2

The Effect of Gap Spacing Between Solar Panel Clusters on Crop Biomass Yields, Nutrients, and the Microenvironment in a Dual-Use Agrivoltaic System

Oleskewicz, Kristen 10 April 2020 (has links) (PDF)
Agrivoltaic (AV) systems are dual-use land systems that consist of elevated solar panels with crops grown underneath. They offer a solution to the increasing demand for food production and clean renewable energy. The main concern regarding AV systems is the reduced availability of light to crops below the panels. Research to date shows that AV systems are quite productive with total energy and crop production exceeding the outputs of either solar farms or crop production alone. Research also shows that solar panels affect the microenvironment below the panels. The research on AV systems so far considers altering panel density to increase radiation to the crops by varying the distance between rows of panels in an AV solar array. This study examines the crop outputs for Swiss chard, kale, pepper, and broccoli in an AV system with different gap spacings of 2, 3, 4, or 5 feet (AV plots) between panel clusters within rows to determine how much spacing between solar panels is optimal for crop production by comparing these system yields to full sun crop production. This study also examines the effect of the AV system on crop nutrient levels, on soil water content, and crop leaf temperature below the panels. Ultimately, the biomass crop yields of AV plots are restricted significantly for Swiss chard, kale, or pepper compared against the full sun control plot yields but not for broccoli stem + leaf yields. The 4-ft or 5-ft gap distances between panels yield the highest crop biomass of the AV shaded plots. Nutrient levels tend to increase with more shade but the trend is only significant for Swiss chard nitrogen and phosphorus concentrations, pepper potassium concentrations, and broccoli phosphorus concentrations. For soil water content it is found that panels have some effect on evapotranspiration and rainfall redistribution at the soil level. Leaf temperatures in the AV plots are lower than leaf temperatures in the control plots on sunny days but not on cloudy days.
3

Thermal Modelling Of An Agrivoltaic System : 3D performance analysis for bificial PV-modules

Qadir, Omar, Cem Parlak, Sertac January 2022 (has links)
abstract Recognizing the importance of the Food, Energy and Water -nexus sustainable approaches and develop according to their framework, would help to achieve global goals such as water security, energy security and food security. And because of the increasing number of human beings, energy demand, food demand, massive amount of land must be used in order to meet these demands. Agrivoltaic system shows promising potential in helping these areas to thrive, the system combines farm activities with PV energy system on the same piece of land, thus, its fits the requirements of Food, Energy and Water -nexus as a valid solution in optimizing the usage in land along with irrigation. However, understanding of the microclimatic conditions in an Agrivoltaic system is essential for adequate crop management because it represents the physical conditions experienced by organisms, in turn these conditions constrain the crop yield. The issue is that this topic is not fully understood, hence, this research studies the important factors affecting microclimatic conditions. After surveying relative literature review regarding Agrivoltaic system and the surrounding microclimate, a model of the reference plant at KärrboPrästgård in Sweden was developed in the simulation software ‘’Solidworks’’. This was done in order to properly analyze the influence between microclimate versus PV system. The model was then validated with measurements taken from the reference plant such as, temperature and solar intensity absorbed by the panels. And had relatively similar trendlines, which confirmed that the model was in order however, there was a slight difference in both of temperature and solar intensity diagrams. Regarding the result obtained from the CFD simulation showed that the implantation of PV panels could potentially conduct unwanted heat if the air could not travel always to the source of heat and exchange with cooler air. The result also showed the direction of the air showed important value, because when the direction of the air was heading against the front side of the panels, less velocity in air reached the next rows of panels.     Preface This degree project was carried out in the School of Business, Society and Engineering (EST) at Mälardalen University within the framework of Future Energy Center. It aims to develop a detailed CFD model of a vertically mounted agrivoltaic system within the Swedish Energy Agency project “Evaluation of the first agrivoltaic system in Sweden”. We want to thank Pietro Campana for arranging the project along with our main supervisor, Sebastian Zainali, who has guided and assisted us throughout the project.
4

Bilan hydrique et développement de culture sous panneaux photovoltaïques dynamiques : de la modélisation à l’évaluation de solutions agrivoltaïques / Water budget and crop growth under dynamic photovoltaic panels : modelling and assessment of agrivoltaic systems

Elamri, Yassin 15 December 2017 (has links)
L’agrivoltaïque, association sur une même surface d’une production agricole et d’une production d’énergie d’origine photovoltaïque, apparait aujourd’hui comme une solution innovante pour atténuer les effets du changement climatique, notamment sur le secteur agricole. Déjà imaginé en 1982, les premières expérimentations débutées à Montpellier (France) en 2010 ont montré la pertinence de cette association à travers un maintien des rendements sous certaines conditions, une meilleure efficience d’utilisation du sol ainsi qu’une diminution de la consommation en eau des cultures sous ombrage. Suite à ces travaux pionniers réalisés sous des panneaux photovoltaïques à inclinaison fixe, l’utilisation de panneaux dynamiques à inclinaison variable est apparue nécessaire pour réduire l’hétérogénéité du rayonnement disponible pour la culture mais aussi, adapter la stratégie d’ombrage aux besoins radiatifs de la culture au cours de son développement.La présente thèse avait pour objectif de caractériser et de modéliser l’impact de la présence de panneaux solaires sur le bilan hydrique d’une culture conduite sous dispositif agrivoltaïque dynamique en vue d’optimiser la stratégie d’irrigation et le pilotage de l’inclinaison des panneaux. Les expérimentations menées sur une culture de laitues ont mis en évidence l’intérêt de panneaux dynamiques afin de réduire les hétérogénéités radiatives. Le développement d’un modèle de redistribution des pluies par les panneaux photovoltaïques a permis la mise en œuvre d’une stratégie de pilotage de l’inclinaison en temps réel a permis d’homogénéiser les cumuls observés au sol. L’adaptation d’un modèle de bilan hydrique et de développement de culture par l’ajout d’un module décrivant la dynamique stomatique sous ombrage fluctuant a permis de décrire la consommation en eau de la culture et son développement sous différentes stratégies de pilotage de l’ombrage. Enfin, différentes stratégies de pilotage de l’inclinaison des panneaux photovoltaïque ont pu être simulées et évaluées à l’aide d’un indicateur globale intégrant l’efficience d’utilisation du sol, la productivité de l’eau, le décalage de maturité et les sources d’hétérogénéités pouvant affecter la production de laitues. / Agrivoltaism, defined as the association on the same land of agricultural and photovoltaic energy production, appears as an innovating concept to dampen some of the effects of climate change, in the agricultural sector. Although the concept was already imagined in 1982, the first experimentations started in 2010 at Montpellier (France) and showed the relevance of this combination by the maintenance of crop yield under certain conditions, the increase of land use efficiency and a reduction of water consumption for the tested crops. Following this pioneering work done under fixed (but not horizontal) photovoltaic panels, the use of "dynamic" panels, i.e. panels with a variable tilting angle, appears necessary to reduce the spatial heterogeneity of the transmitted radiation but also to adapt the shading strategy to the radiation amount required for crop growth.This thesis aims to characterize and to model the impact of the photovoltaic panels on the water budget of the cultivated plot and to progress towards the optimization of irrigation strategies in such systems controlled by the variations in time of the tilting angle of the panels. Experimentations conduced on lettuces showed the benefits of "dynamic" photovoltaic panels to reduce the radiative heterogeneity. Accounting for rain redistribution by the solar panels permits the implementation of a real time strategy to reduce rainfall heterogeneity on the ground surface. The derivation of a water budget and crop development model which describes the dynamics of stomatal conductance under fluctuating shading allows a better simulation of water consumption and crop development for different shading strategies. Finally, various strategies for the piloting of the solar panels could be tested and evaluated by a new, global index combining land use efficiency, water productivity, maturity delays and heterogeneities (in rain and radiation) which can impact production.
5

SHADING ANALYSIS OF AGRIVOLTAIC SYSTEMS : The shading’s effect on lettuce and potato from elevated agrivoltaic system in Sweden

Farid, Komail, Guleed, Ahmad January 2023 (has links)
The world is progressing towards a more sustainable society, where renewable energy sources, including solar energy, play a crucial role. This study aims to address the conflict between agriculture and energy production by exploring the installation of solar panels on farmland. Four scenarios are considered, with varying parameters such as latitude, azimuth, slope, and row distance between photovoltaic (PV) modules. The study focuses on two different crops, lettuce and potato, which have varying tolerances to shading. The objective is to understand how the shadows cast by solar panels affect the growth of these crops. To analyze the impact of shading, the PVsyst software program is utilized to obtain PAR values for each scenario. The calculations are performed using Excel equations. The literature review encompasses scientific sources that provide insights into both PV technology and agriculture, bolstering the research findings. To ensure realism and manage simulation time, certain delimitations were made. These include limiting the study to two cities in Sweden, comparing only two crops, and conducting simulations during the summer period. 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 photovoltaic (PV) systems. However, it is not advisable to implement AV systems in areas where sensitive crops like lettuce, which necessitate a significant number of sun hours with high solar intensity.
6

A Contingency Framework for Assessing the Commercial Potential of Utility-scale Agrivoltaics

Larsson, Filippa January 2023 (has links)
Purpose - In the pursuit of renewable energy sources, solar photovoltaic (PV) is predicted to become the single biggest global source of energy by the year of 2027, part of a trilemma involving climate change, biodiversity and food security. Agrivoltaic (AV) systems, the co-location and potential symbiosis between agricultural activities and solar PV, has thereby arisen as a potential solution for dual land-use. The research within this area is novel, and scholars agree that there is a need for the conceptualization of utility-scale AV in general, and the commercialization process of such systems in particular. Thereby, the purpose of this study is to unravel the key factors, activities and stakeholder involvement in order to assess the commercial potential of utility-scale AV. By addressing research questions: RQ1. What are the key factors for assessing the commercial potential of utility-scale AV?, RQ2. Which activities are essential to address these factors? and RQ3. Who are the key stakeholders that need to be involved in these activities?, a contingency framework for the assessment process has been developed. Method - In order to fulfill the purpose of this study utility-scale AV was approached as a Technology Innovation System (TIS) where the solar energy actor Sunna Group AB (Sunna) enabled insight to the potential industry context of utility-scale AV. Respondents were sampled within the TIS, forming the prerequisites for this multiple case study. Empirical data were collected in three phases: 1) Exploratory, 2) Semi-structured and 3) Final workshop, resulting in 3 workshops and 17 interviews, analyzed by a thematic analysis.  Findings - The thematic analysis resulted in four main themes: 1) Socio-political factors, 2) Techno-economical factors, 3) Meso activities for commercialization and 4) Macro activities for commercialization, under which seven key factors, six overarching activities and the stakeholder involvement in these activities, were revealed. These further formed a contingency framework providing an overview of how these building blocks are interlinked.  Theoretical &amp; practical implications - The resulting framework provides an overview and synthesizes the commercialization of utility-scale AV, bridging the gap between stakeholder involvement and the key factors for assessing the commercial potential. The practical implications of this study primarily involve the solar energy sector, yet deemed to be of value to all potential stakeholders within the ecosystem of AV. Limitations &amp; future research - The limitations of this study includes the potential exclusion of stakeholders within the data collection process due to the complex stakeholder configuration of AV, as well as the geographical constraints limiting this study to the context of Sweden. Future research is encouraged within several fields of this novel research area, predominantly including stakeholder involvement, business model configuration and how to mobilize the synergy sought in technology development between the solar energy- and agricultural sector.

Page generated in 0.0339 seconds