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  • 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

Design of a controlled environment agricultural plant inspection robot

Chen, Howard 01 May 2012 (has links)
Without an increase in cropland, agricultural efficiency must be tripled in the next 50 years to sustain the increased demand for food. Controlled environment agriculture (CEA) systems are likely to play an important role in the increase of agricultural efficiency. CEA systems, however, require constant observation because decisions must be quickly made when plants show signs of stress. A visual inspection system that uses a robotic camera system would permit visual access to inaccessible plants in a large hydroponics operation or allows an observer to remotely inspect plants for multiple small or remote CEA operations, whereas a dedicated CEA specialist would be beneficial but impractical under present conditions. This thesis presents a theoretical design for a plant inspection robot. The design parameters, design process, and the system specification necessary to satisfy the design constraints were examined for this system. The design analysis revealed that the major components of the plant inspection robot must be designed sequentially, starting with the imaging system. The imaging system design revealed that the system parameters were governed by illumination, shape and size of the object, and the desired detail. The motion system design was governed by velocity, acceleration, work area, and accuracy. An example design for a system used for visual inspection of 289 romaine lettuce plants was presented. This design was shown to be feasible from the theoretical perspective and could be built from commercially-available components, reducing development time and cost.
2

A Liquid Desiccant Cycle for Dehumidification and Fresh Water Supply in Controlled Environment Agriculture

Lefers, Ryan 12 1900 (has links)
Controlled environment agriculture allows the production of fresh food indoors from global locations and contexts where it would not otherwise be possible. Growers in extreme climates and urban areas produce food locally indoors, saving thousands of food import miles and capitalizing upon the demand for fresh, tasty, and nutritious food. However, the growing of food, both indoors and outdoors, consumes huge quantities of water - as much as 70-80% of global fresh water supplies. The utilization of liquid desiccants in a closed indoor agriculture cycle provides the possibility of capturing plant-transpired water vapor. The regeneration/desalination of these liquid desiccants offers the potential to recover fresh water for irrigation and also to re-concentrate the desiccants for continued dehumidification. Through the utilization of solar thermal energy, the process can be completed with a very small to zero grid-energy footprint. The primary research in this dissertation focused on two areas: the dehumidification of indoor environments utilizing liquid desiccants inside membrane contactors and the regeneration of these desiccants using membrane distillation. Triple-bore PVDF hollow fiber membranes yielded dehumidification permeance rates around 0.25-0.31 g m-2 h-1 Pa-1 in lab-scale trials. A vacuum membrane distillation unit utilizing PVDF fibers yielded a flux of 2.8-7.0 kg m-2 hr-1. When the membrane contactor dehumidification system was applied in a bench scale controlled environment agriculture setup, the relative humidity levels responded dynamically to both plant transpiration and dehumidification rates, reaching dynamic equilibrium levels during day and night cycles. In addition, recovered fresh water from distillation was successfully applied for irrigation of crops and concentrated desiccants were successfully reused for dehumidification. If applied in practice, the liquid desiccant system for controlled environment agriculture offers the potential to reduce water use in controlled environment agriculture by as much as ~99%.
3

Development of a New Hydroponic Nutrient Management Strategy and a Tool to Assess Microclimate Conditions in Indoor Leafy Green Production

Papio, Giovanni A. January 2021 (has links)
No description available.
4

Effects of Soilless Substrate Systems and Environmental Conditions on Yield, Total Soluble Solids, and Titratable Acidity of Greenhouse Strawberry (Fragaria × ananassa)

McKean, Thomas January 2019 (has links)
No description available.
5

THE EFFECTS OF PLANT-DERIVED PROTEIN HYDROLYSATES ON THE GROWTH, QUALITY, AND PHYSIOLOGY OF GREENHOUSE CROPS

Seunghyun Choi (10347350) 30 July 2021 (has links)
Biostimulants offer an innovative approach to potentially improve crop yield and quality under abiotic stresses. Particularly, plant-derived protein hydrolysates (PH), a mixture of amino acids and soluble peptides from enzymatic or chemical hydrolysis of agricultural waste, are gaining global interest due to their sustainability and positive effects on crops. However, a functional role of the PH in crop yield and quality remains uncertain and is proposed to be associated with its phytohormone-like activities or serve as an additional nitrogen (N) source. Besides, the effects of PH on crop yield and quality are limited in intensive production systems such as greenhouse facilities. The purposes of this research are to examine the effects and mechanisms of PH on crops and to assess the potential of PH application to reduce fertilizer use in crop production. The specific objectives were to; 1) elucidate the hormone-like activities of PH in the adventitious rooting formation of cuttings, 2) evaluate the effects of different PH application methods on greenhouse crop yield and quality under different N levels when plants are grown with a commercial growing medium, and 3) examine the effects of PH application methods on yield and quality of hydroponically grown lettuce under different N levels and forms. Three conclusions were that 1) <a>the hormonal effects of PH are attributed to brassinosteroid-mediated processes, and PH has overlapping functions with auxin during adventitious rooting of cuttings in a plant species-specific manner</a>, 2) root application of PH (PH-R) effectively improves nutrient uptake compared to foliar spray of PH (PH-F), subsequently, increases the lettuce and tomato yield and quality regardless of N levels while PH-R did not change the chemical properties of growing media, and 3) PH-R effectively increases root growth, and subsequently, improving shoot yield and quality with significant PH × N levels and PH × NO<sub>3</sub>:NH<sub>4 </sub>ratios interactions. Also, PH-R counteracted the negative effects of low NO<sub>3</sub>:NH<sub>4 </sub>ratios on lettuce yield. The outcomes provide the optimization of PH and N fertilization in modern sustainable greenhouse production and the development of a new strategy for producing high-quality greenhouse crops with improved nutrient use efficiency.
6

The Quest for the Hydroponic Pepper : Applying Design Research Methodology to Develop Support Tools for Successfully Designing a Post-harvest System for a Plant Factory

Antser, Charlie, Lundvall, Kimmy January 2021 (has links)
The world is facing a food shortage as the world’s population increases and arable land decreases. Despite this, the food industry is wasteful, and 30% - 40% of all produced food is lost before reaching the end consumer. Emerging technologies aim to increase the amount of food that can be grown per m2 or allow the growing of food in climates or on lands previously impossible. Four main farming techniques utilising these emerging technologies are Controlled Environment Agriculture, Hydroponic Farming, Urban Farming and Vertical farming. When used together, these techniques form the basis for what can be called a Plant Factory. Despite the positive effects these technologies have on the production rate, few Plant Factories have managed to achieve profitability. By creating support for developing the post-harvesting system for a plant factory, this thesis aims to aid in the development of profitable plant factories. The thesis uses Design Research Methodology to achieve this aim in three parts. The first part identifies the underlying factors of the post-harvesting system affecting plant factory profitability. The second presents a set of support components that will aid the developers to improve key factors affecting profitability. The third part is a case study where the support components applicability at targeting the key factors are evaluated, and suggestions for further improvements and testing of the support is suggested.  Further, using Design Research Methodology, the methods used to develop support in this thesis are presented to easily be replicated by other researchers to aid them in developing support for other industries and circumstances. The suitability of the developed support was tested using the principles of an initial DS-II. The developed support proved very useful for the investigated case, and with its conditions, the application evaluation was considered a partial success. Two key factors were successfully improved and indicated that the intended support is ready for a comprehensive DS-II. A third support component needs more work to provide the intended support fully. Therefore a second  PS iteration is recommended before a comprehensive DS-II is done to increase its value.
7

<strong>THE  EVALUATION OF MODULAR MANUFACTURING IN CONTROLLED ENVIRONMENT AGRICULTURE FOR  REPURPOSED URBAN SPACES</strong>

Mikael Borge (16648569) 01 August 2023 (has links)
<p>This thesis aims to evaluate a Modular Manufacturing (MM) technical approach to Controlled Environment Agriculture (CEA) for cultivating plant food crops in a repurposed urban space. The specific approach was to fit a modular hydroponic CEA system into an insulated cooler box with environmental control to act as a micro plant factory. The feasibility of the approach was evaluated and a benchmark comparison between repurposed urban space and controlled lab environments was produced.</p><p>Possessing accessibility and affordability to desired quantitatively and nutritious food is a pillar for a healthy lifestyle, yet food insecurity is a growing problem worldwide, in industrial as well as industrializing nations. Food insecurity is defined as “lacking the ability to meet nutritional needs at one or multiple times during the year.” [1] Though Developing countries tend to score poorly on the Food Security Index [2], the issue is common in developed countries as well, where countries like the U.S. Possess a household food insecurity rate of above 10% [1]. Especially, subgroups of the urban population and university students in developed countries are represented at a higher rate concerning food insecurity [3], due to food insecurity’s dependence on socioeconomic factors such as purchasing power and local accessibility.</p><p>Bringing production close to the consumers or to the Point-of-Need (PoN) would be a valuable tool for supplementing traditional food crop production and increasing access to high-quality food for groups exposed to food insecurity. This is especially attractive in densely populated areas and college campuses, where real estate is prime. Bringing production to the PoN does however carry certain challenges, such as severe resource restrictions, which are not present in traditional agricultural production in rural areas where there is vast access to land, water, and plenty of sunlight. Pushing the boundaries of CEA research, technology, and application areas will be crucial for the utilization of nontraditional agricultural land, agricultural resource optimization, and food security improvements in difficult-to-farm environments to facilitate delivery to PoN.</p><p><br></p><p><b>Salient outcomes:</b> The salient outcomes of this research were that a MM platform was proven to be feasible for CEA cultivation of food crops in a repurposed urban space as well as a controlled location. Specimens cultivated in a repurposed urban space were shown to have a lower growth rate compared to a controlled location, but the important comparison is to the currently nonexistent productivity in such spaces.</p><p><b>Intellectual merit:</b> The MM CEA platform was designed, prototyped, and tested using components-of-the-shelf (COTS) as recommended by frugal engineering methodology [4]. This manufacturing platform was engineered for a case study for repurposing unused “garage space” on the college campus at Purdue University. The platform was further used for a set of studies to evaluate the feasibility of the MM platform and the production efficiency of the platform not only in a repurposed urban space but also across harsh environments across winter-spring seasons. Romaine lettuce cultivars were used as a sample plant for winter and spring studies due to their property as a popular consumable, nutritious, and relatively short growth time for better productivity. The following research issues were addressed by this research: (1) design of a modular manufacturing module; (2) testing of the module in the indoor controlled lab environment; (3) advancing design based on findings in no.2; (4) CEA testing of the integration of multiple modules (two and water supply) in the Purdue University garage (living lab) and the indoor lab environment.</p><p><b>Broader Impact:</b> The results from this research could serve as a proof-of-concept to validate the feasibility of functional modules and their integration in scaled-up urban food crop production using repurposed space. This case study especially could open opportunities for college campuses across the US (and the world), to repurpose multi-storied garage spaces for healthy food production at PoN, for example, accessible to students’ dorms and cafeterias. This MM model could further be extended to other forms of urban areas for food security and production in communities in the vicinity of garages and similar spaces in form. Utilizing unrecognized space resources in an otherwise resource-restricted environment could be the supplemental production needed to fight food desertification and insecurity in urban locations. Bringing food production to the PoN would increase the accessibility of high-quality and nutritious fresh produce, improving conditions for localized food insecurity problems.</p>
8

Life Cycle Assessment for Improving Sustainability of Aquaculture and Aquaponics

April Janai Arbour (17583837) 09 December 2023 (has links)
<p dir="ltr">Controlled environment agriculture (CEA) is a practice of food production under optimized conditions to intensify production yield, and thus has potential for addressing food security for a growing population. Aquaculture and aquaponics are two types of CEA that can produce aquatic animals along with plants using non-arable lands and lower inputs of water and nutrients. However, their operations have high energy consumption and generate considerable nutrient-rich sludge and wastewater, making their environmental performance an emerging research focus. This thesis quantitively analyzed the environmental sustainability of aquaponics and aquaculture production using life cycle assessment (LCA).</p><p dir="ltr">The LCA on aquaponics evaluated a marine aquaponics production system that grew shrimp, red orache, minutina and okahajiki, and analyzed the effect of salinity, C/N ratio, and shrimp-to-plant stocking density. The grow-out stage accounted for over 90% of total environmental impacts with electricity use as the predominant contributor. The marine aquaponic production exhibited best environmental performance when operated at low salinity (10 ppt), and high C/N ratio (15) and stocking density (5:1), which can be further improved by 95–99% via the use of wind power as electricity source. Additionally, variation in the prices of aquaponic products was found to improve the system’s environmental impacts by up to 8%.</p><p dir="ltr">The aquaculture LCA focused on shrimp recirculating aquaculture systems (RAS) and evaluated the environmental feasibility of microalgae-based wastewater treatment. Microalgae treatment effectively removed 74% of phosphate in RAS wastewater and thus reduced the freshwater eutrophication potential by 55%. However, its remediation performance was inferior to activated sludge treatment due to different operation scales. Electricity was the principal hotspot of microalgae treatment and made up over 99% of all the environmental impacts, which can be considerably decreased by reducing coal use in the electricity supply. Three utilization pathways for algal biomass (feed ingredient, biodiesel and biogas) were investigated; however, only biogas production was found to show environmental benefits to marine eutrophication remediation owing to the low biomass quantity produced.</p><p dir="ltr">While <a href="" target="_blank">aquaculture and aquaponics</a> play important roles in meeting the globally growing demand for seafood, this thesis provides valuable life cycle inventory data for these fields. Moreover, the LCA models developed in this thesis are useful decision-making tools for aquaculture and aquaponic producers to adapt farming practices with lower environmental footprint.</p>
9

Effects of Low Nutrient Solution pH on Hydroponic Leafy Green Plant Growth, NutrientConcentration of Leaf Tissue, and Pythium Zoospore Infection

Gillespie, Daniel Patrick January 2019 (has links)
No description available.
10

Improving Climate Control and Energy Performance in Greenhouses and Livestock Houses: Modelling Advances and Experimental Results

Costantino, Andrea 16 December 2021 (has links)
[IT] Importanti cambiamenti sociodemografici, come la crescita della popolazione mondiale e l’urbanizzazione, stanno incrementando il fabbisogno di alimenti a livello mondiale. In contemporanea si sta assistendo ad una profonda trasformazione della dieta umana che tende sempre più a prediligere prodotti di origine animale, frutta e verdura al posto dei cereali. In quest’ottica, serre e stalle per l’allevamento intensivo possono ricoprire un ruolo di spicco, in quanto in grado di produrre tali alimenti con dei rendimenti decisamente maggiori rispetto a quelli che caratterizzano la produzione di vegetali in campo aperto e l’allevamento estensivo. Tra i vari fattori che contribuiscono ad incrementare la produttività di questi edifici agricoli vi è il controllo delle condizioni climatiche interne. Tale controllo del clima interno avviene, in molti casi, attraverso sistemi meccanici il cui utilizzo causa un considerevole consumo energetico che costituisce una minaccia per la transizione verso un’agricoltura più sostenibile. L’obiettivo generale di questa tesi è, quindi, di contribuire alla transizione verso un’agricoltura più sostenibile attraverso il miglioramento della prestazione energetica per il controllo climatico di serre e stalle per l’allevamento intensivo. Per raggiungere tale obiettivo, è stato adottato un triplice approccio basato su un’analisi di letteratura, campagne sperimentali di monitoraggio ed attività di modellazione energetica. L’analisi di letteratura è stata svolta con il fine di districare la complessa rete di relazioni esistente tra controllo climatico e altri domini di interesse della produzione agricola. Il nesso tra prestazione energetica e controllo climatico è stato approfondito analizzando dei set di dati reali acquisiti in una serra e due porcilaie attraverso campagne di monitoraggio. Questo nesso è stato ulteriormente approfondito adottando un approccio numerico che ha portato allo sviluppo e validazione di tre modelli di simulazione energetica per serre, per stalle da polli da carne e per stalle da suini da ingrasso. Ciascun modello di simulazione integra le principali caratteristiche tipiche di tali edifici per stimare con accuratezza i profili temporali delle condizioni ambientali interne e del consumo di energia termica ed elettrica. Le potenzialità di questi modelli nel migliorare la prestazione energetica e le condizioni climatiche di serre e stalle sono state esplorate analizzando specifiche problematiche relazionate al consumo energetico. Il modello energetico per le stalle per polli da carne, infatti, è stato adottato per valutare le potenzialità di un nuovo approccio per la progettazione energeticamente efficiente dell’involucro basato sull’energia primaria. Lo stesso modello è stato usato per valutare la variazione del consumo energetico causata dall’adozione di una strategia di ventilazione mirata al miglioramento del benessere dei polli allevati attraverso la riduzione della concentrazione interna di gas nocivi. Questa tesi contribuisce alla transizione verso una agricoltura più sostenibile fornendo nuove conoscenze e strumenti necessari al miglioramento della prestazione energetica per controllo climatico di serre e stalle per l’allevamento intensivo. Le analisi svolte, infatti, quantificano potenziali riduzioni del consumo energetico ottenibili attraverso l’implementazione di misure di efficientamento energetico, sia a livello di involucro (isolamento termico) che a livello di sistema di controllo climatico (ventilatori a portata variabile). Ulteriori misure per l’efficientamento energetico potrebbero essere valutate attraverso tali modelli che rappresentano importanti risultati di questa ricerca. Essi, infatti, potrebbero avere ricadute positive a livello locale in quanto vari portatori d’interesse (agricoltori, ingegneri e fabbricanti) potrebbero adottarli come strumenti di supporto alle decisioni per valutare nuove tecnologie, strategie e soluzioni mirate alla diminuzione del consumo energetico di serre e stalle. Questi nuovi modelli rappresentano anche un solido punto di partenza per future ricerche in questo campo. Futuri sviluppi potrebbero portare alla creazione di ulteriori moduli di calcolo per valutare altri aspetti, come la variazione della produttività, l’emissione di contaminanti e il benessere animale. Le nuove conoscenze generate in questa tesi potrebbero avere ricadute positive anche a livello globale, in quanto potrebbero rappresentare i fondamenti tecnici per nuovi quadri normativi e schemi di incentivi mirati al miglioramento della performance energetica di edifici agricoli controllati climaticamente attraverso una strategia di tipo top-down. / [ES] Importantes cambios sociodemográficos están conduciendo hacia un considerable crecimiento de la demanda de alimentos a nivel mundial. Al mismo tiempo se está observando una profunda transformación de la dieta humana, que tiende a incluir más productos de origen animal, fruta y verdura. Invernaderos y granjas de ganadería intensiva pueden desempeñar un papel principal, debido a que proporcionan los productos agrícolas necesarios con rendimientos notablemente mayores que los de la producción en campo abierto y de la ganadería extensiva. Entre los factores que contribuyen a incrementar la productividad de estos edificios agrícolas se sitúa el control de las condiciones climáticas internas. Dicho control se realiza a través de sistemas mecánicos cuyo uso causa un considerable consumo energético que representa una amenaza para la transición hacia una agricultura sostenible. El objetivo de esta tesis es contribuir a la transición hacia una agricultura más sostenible a través de la mejora de la prestación energética por control climático de invernaderos y granjas de ganadería intensiva. Para alcanzar dicho objetivo, se ha adoptado un enfoque triple basado en un análisis de literatura, campañas experimentales de monitorización y actividades de modelización energética. El análisis de literatura se ha llevado a cabo con el fin de desentrañar la red de relaciones existentes entre el control climático y otros dominios de interés de la producción agrícola. El nexo entre prestación energética y control climático se ha acometido analizando conjuntos de datos reales, adquiridos en un invernadero y dos granjas de cerdos. El análisis de dicho nexo se ha profundizado adoptando un enfoque numérico que ha llevado al desarrollo y validación de tres modelos de simulación energética para invernaderos y para granjas de pollos y cerdos. Las potencialidades de estos modelos para la mejora de las prestaciones energéticas y las condiciones climáticas se han explorado analizando problemáticas específicas. El modelo energético para granjas de pollos se ha adoptado para el diseño energéticamente eficiente de la envolvente de este tipo de edificio. El mismo modelo se ha usado para evaluar las variaciones de consumo energético causadas por la adopción de una estrategia de ventilación orientada a la mejora del bienestar de los pollos. Esta tesis contribuye a la transición hacia una agricultura más sostenible proporcionando nuevos conocimientos e instrumentos para la mejora de la prestación energética para el control climático de invernaderos y granjas. Los análisis realizados cuantifican potenciales disminuciones del consumo energético alcanzables a través de la implementación de medidas para la eficiencia energética a nivel de envolvente (aislamiento térmico) y a nivel de sistema de control climático (ventiladores con caudal variable). Ulteriores medidas para la eficiencia energética podrían evaluarse a través de dichos modelos que representan importantes resultados de esta investigación. Estos modelos podrían tener repercusiones positivas a nivel local, ya que muchas partes interesadas (agricultores, ingenieros y fabricantes) podrían adoptarlos como instrumentos de apoyo a la toma de decisiones para evaluar nuevas tecnologías y estrategias orientadas a la disminución del consumo energético. Estos nuevos modelos representan también un sólido punto de partida para futuras investigaciones en este campo. Futuros desarrollos podrían implementar nuevos módulos de cálculos para evaluar otros aspectos, como la variación de la productividad, la emisión de contaminantes y el bienestar animal. Los nuevos conocimientos generados en esta tesis podrían tener repercusiones positivas incluso a nivel global, puesto que podrían representar los fundamentos técnicos para nuevos marcos normativos y sistemas de incentivos orientados a la mejora de la prestación energética de edificios agrícolas controlados climáticamente a través de una estrategia de tipo top-down. / [CA] Importants canvis sociodemogràfics estan conduint cap a un considerable creixement de la demanda d'aliments a nivell mundial. Al mateix temps s'està observant una profunda transformació de la dieta humana, que tendeix a incloure més productes d'origen animal, fruita i verdura. Hivernacles i granges de ramaderia intensiva poden exercir un paper principal, pel fet que proporcionen els productes agrícoles necessaris amb rendiments notablement majors que els de la producció en camp obert i de la ramaderia extensiva. Entre els factors que contribueixen a incrementar la productivitat d'aquests edificis agrícoles se situa el control de les condicions climàtiques internes. Aquest control del clima intern es realitza a través de sistemes mecànics, l'ús dels quals causa un considerable consum energètic que representa una amenaça per a la transició cap a una agricultura sostenible. L'objectiu general d'aquesta tesi és contribuir a la transició cap a una agricultura més sostenible a través de la millora de la prestació energètica per al control climàtic d'hivernacles i granges de ramaderia intensiva. Per a aconseguir aquest objectiu, s'ha adoptat un enfocament triple basat en una anàlisi de literatura, campanyes experimentals de monitoratge i activitats de modelització energètica. L'anàlisi de literatura s'ha dut a terme amb la finalitat de desentranyar la complexa xarxa de relacions existents entre el control climàtic i altres dominis d'interés de la producció agrícola. El nexe entre prestació energètica i control climàtic s'ha analitzat amb conjunts de dades reals, adquirides en un hivernacle i dues granges de porcs. L'anàlisi d'aquest nexe s'ha aprofundit encara més adoptant un enfocament numèric que ha portat al desenvolupament i validació de tres models de simulació energètica per a hivernacles i per a granges de pollastres i porcs d'engreixament. Les potencialitats d'aquests models per a la millora de les prestacions energètiques i les condicions climàtiques s'han explorat analitzant problemàtiques específiques. El model energètic per a granges de pollastres s'ha adoptat per al disseny energèticament eficient de l'envolupant d'aquesta mena d'edifici. El mateix model s'ha usat per a avaluar les variacions de consum energètic causades per l'adopció d'una estratègia de ventilació orientada a la millora del benestar dels pollastres. Aquesta tesi contribueix a la transició cap a una agricultura més sostenible proporcionant nous coneixements i instruments per a la millora de la prestació energètica per al control climàtic d'hivernacles i granges. Les anàlisis realitzades quantifiquen potencials disminucions del consum energètic assolibles a través de la implementació de mesures per a l'eficiència energètica tant a nivell d'envolupant (aïllament tèrmic) com a nivell de sistema de control climàtic (ventiladors amb cabal variable). Ulteriors mesures per a l'eficiència energètica podrien avaluar-se a través d'aquests models que representen importants resultats d'aquesta investigació. Aquests models podrien tindre repercussions positives a nivell local, ja que moltes parts interessades (agricultors, enginyers i fabricants) podrien adoptar-los com a instruments de suport a la presa de decisions per a avaluar noves tecnologies i estratègies orientades a la disminució del consum energètic d'hivernacles i granges. Aquests nous models representen també un sòlid punt de partida per a futures investigacions en aquest camp. Futurs desenvolupaments podrien implementar nous mòduls de càlculs per a avaluar altres aspectes, com la variació de la productivitat, l'emissió de contaminants i el benestar animal. Els nous coneixements generats en aquesta tesi podrien tindre repercussions positives fins i tot a nivell global, ja que podrien representar els fonaments tècnics per a nous marcs normatius i sistemes d'incentius orientats a la millora de la prestació energètica d'edificis agrícoles controlats climàticament a través d'una estratègia de tipus top-down. / [EN] Socio-demographic trends, such as population growth and urbanization, are leading to a significant increase of the world food demand. At the same time, there is a shift of the human diet toward livestock products, vegetables, and fruit rather than cereals. Greenhouses and livestock houses can play a primary role since they can supply the necessary agricultural products with higher yields than on-field crop production and extensive animal farming. One way in which productivity is enhanced in these agricultural buildings is by a fine-tuned control of the indoor climate conditions. For this purpose, mechanical climate control systems are often adopted, but they entail a considerable energy consumption whose estimated increase may jeopardize the transition toward a sustainable agriculture. The overall objective of this thesis, hence, is to contribute to the transition toward a sustainable agriculture by improving the energy performance for climate control of greenhouses and livestock houses. To achieve this objective, a three-pronged approach was taken involving a literature review, experimental monitoring campaigns, and energy modelling activities. The literature review was performed to unpick the tangle of mutual relations between climate control and other domains of agricultural production. The nexus between energy performance and climate control was investigated analyzing real datasets acquired through monitoring campaigns performed in a greenhouse and two pig houses. This nexus was further studied adopting a numerical approach which led to the development and validation of three energy simulation models for greenhouses, broiler houses and pig houses. Each simulation model integrates the main features typical of greenhouses and livestock houses to estimate the time profiles of lumped indoor climate conditions and thermal and electrical energy consumption. The opportunities in improving the energy performance and the indoor climate conditions provided by the developed energy models were explored by analyzing specific energy-related problems. The broiler house energy model was adopted to evaluate the potentialities of a new primary energy approach for the energy-efficient envelope design of broiler houses. The same model was applied to evaluate the variation of energy consumption achieved by an improved ventilation strategy aimed at enhancing broiler welfare by reducing indoor noxious gas concentrations. This thesis contributes to the transition toward a more sustainable agriculture providing new knowledge and tools necessary for improving the energy performance for climate control of greenhouses and livestock houses. The performed analyses, in fact, quantify potential decrease of energy consumption achievable through the implementation of energy-efficient measures at both envelope -thermal insulation- and climate control system -variable angular speed fans- level. Further energy-efficient measures could be evaluated adopting the developed energy simulation models that are valuable outputs of this investigation. These models could have a positive impact at local level since stakeholders -farmers, engineers, and manufacturers- could adopt them as decision support tools for the evaluation of new technologies, strategies and solutions aimed at decreasing the overall energy consumption of greenhouses and livestock houses. These novel models represent also a robust starting point for future research in this field. Future advances may lead to the development of further calculation modules to evaluate other aspects of greenhouses and livestock houses, such as productivity variations, contaminant emissions and animal welfare. The new knowledge generated in this thesis could have positive impacts also at global level since it may represent the technical basis for new normative frameworks and incentive schemes aimed at improving the energy performance of climate-controlled agricultural buildings through a top-down approach. / Costantino, A. (2021). Improving Climate Control and Energy Performance in Greenhouses and Livestock Houses: Modelling Advances and Experimental Results [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/178457 / TESIS

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