Greenhouse Structures

Zabeltitz, Christian von

doi:10.1007/978-3-642-14582-7_5

Cited by 9 publications

(5 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In most studies performed on greenhouse crops, an average transmissivity value is applied. However, this transmissivity coefficient varies as a function of many factors, such as type and state of conservation of the covering material, shading, greenhouse geometry and orientation, and day of the year (Zabeltitz, ). For this reason in this study, with the aim of deriving more accurate and specific indoor climate data, climate measurements were taken in a sample of greenhouses.…”

Section: Methodsmentioning

confidence: 99%

Irrigation Water Management in a Mediterranean Greenhouse District: Irrigation Adequacy Assessment

Sánchez

Reca

Martínez

2015

Irrigation and Drainage

View full text Add to dashboard Cite

The sustainability of greenhouse production in semi-arid regions in the Mediterranean basin depends on the availability of water resources. However, the increasing demand for water has caused environmental and water availability concerns. The main objective of this work is to assess irrigation adequacy in an irrigation district located in southern Spain with major water resource problems in terms of both quantity and quality.Two resolution levels were considered: crop and farm. Relative irrigation supply (RIS) index was calculated for a wide sample of crops and farms in the area over the course of four consecutive agricultural seasons.An overall RIS value of 1.12 was obtained. This value indicates that irrigation water exceeded net irrigation needs and, consequently, moderate leaching fractions were applied. However, a high RIS variability was observed. The effect of several factors was statistically analysed to explain this variability.The average water supply to farms was slightly higher than that applied in similar greenhouse districts, possibly due to higher irrigation water salinity. The high variability in the annual relative water supply (ARIS) to the farms confirmed that the main source of variability was farmer management decisions. Irrigation performance in this area could be improved with a proper extension of good irrigation practices. Copyright © 2015 John Wiley & Sons, Ltd. RÉSUMÉLa durabilité de la production sous serre dans les régions semi-arides du bassin méditerranéen dépend de la disponibilité des ressources en eau. Cependant, la demande croissante d'eau a provoqué des préoccupations environnementales à propos de la disponibilité de l'eau. L'objectif principal de ce travail est d'évaluer la pertinence de l'irrigation dans un district d'irrigation situé dans le sud de l'Espagne avec d'importants problèmes de ressources en eau en termes de quantité et de qualité.Deux niveaux de résolution ont été examinés, le premier niveau, celui de la culture, le second niveau, celui de l'exploitation agricole. L'indice d'approvisionnement relatif en irrigation (relative irrigation supply, RIS) a été calculé pour un large échantillon de cultures et de fermes pour quatre campagnes agricoles consécutives.Une valeur de RIS moyenne de 1.12 a été obtenue. Cette valeur indique que la quantité d'eau d'irrigation est supérieure aux besoins d'eau nets et que, par conséquent, des doses de lessivage modérées ont été appliquées. Cependant, une grande variabilité de l'indice RIS a été observée et que nous avons analysé par l'étude statistique de plusieurs facteurs.La fourniture d'eau moyenne des exploitations était légèrement supérieure à celle appliquée dans d'autres districts semblables de cultures sous serres, peut-être en raison de la salinité de l'eau d'irrigation plus élevée. La grande variabilité de l'indice d'approvisionnement relatif d'irrigation annuel (annual relative water supply, ARIS) a confirmé que la principale source de variabilité était la gestion individuelle de l'arrosage par les agriculteurs. ...

show abstract

Section: Methodsmentioning

confidence: 99%

Irrigation Water Management in a Mediterranean Greenhouse District: Irrigation Adequacy Assessment

Sánchez

Reca

Martínez

2015

Irrigation and Drainage

View full text Add to dashboard Cite

show abstract

“…In it we can see, that year 2010 was on average the warmest of the series, and therefore, the more extreme year to explore the potential of a non-selective switchable filter for shortwave radiation, aimed at shading the greenhouse on critical moments of high temperature. Unlike tropical highlands, climate in the tropical lowlands is more extreme; the tropical lowland climate is characterized by prevailing high levels of irradiation, high air temperature and high air humidity (Von Zabeltitz, 1999). In this region, conventionally crops are grown in the open field year round with up to three successive growing seasons.…”

Section: Introduction and Methodologymentioning

confidence: 99%

The perfectly smart greenhouse cover : a simulation study

Romero¹,

Technologie²,

Breugel³

et al. 2018

View full text Add to dashboard Cite

Referaat De huidige studie onderzoekt de mogelijkheden van slimme kasbedekkingsmaterialen met schakelbare optische eigenschappen. In de studie zijn kas-gewas simulatiemodellen gebruikt om het potentiële effect op het microklimaat, het gebruik van hulpbronnen en de groei en ontwikkeling van gewassen te onderzoeken. Drie hoofdgroepen van eigenschappen werden geïdentificeerd om ruwe simulatiestudies uit te voeren: a. filters die zowel PAR-als NIR-straling reflecteren, b. filters die selectief alleen het NIR-gedeelte reflecteren en c. filters die reflecteren in de FIR. Verschillende klimaatregio's en type kassen werden geanalyseerd om rekening te houden met een grote variabiliteit van mogelijke scenario's, waarbij ook rekening werd gehouden met andere gelijktijdige technologische verbeteringen of bestaande concurrerende technieken. De resultaten geven aan dat er een belangrijke potentiële verbetering is in het microklimaat en de opbrengst die samenhangt met het gebruik van schakelbare filters, met name in de "mediterrane/subtropische" klimaatzones, zelfs als de optische eigenschappen niet volledig optimaal zijn. Daarnaast laten we zien dat er behoefte is aan verbetering van de optische eigenschappen van kasdek materialen toegepast in de tropen, zonder behoefte dat ze schakelbaar zijn. Verder onderzoek is nodig om de technische en economische haalbaarheid van deze theoretische filters in meer scenario's te analyseren, ook door nieuwe gewassen in de analyse te betrekken en een optimalisatiestudie van de set-points en schaduwfactoren.

show abstract

“…The devices, pipes and systems pertinent to the hydrogen generation have to be complied with both the ATEX (Atmosphères Explosibles) directives concerning the hydrogen equipments that are 94/9/EC and 99/92/EC (European Commission, 1994, 1999. The directive 94/9/CE establishes the technical requirements for equipment and protective system intended for use in potentially explosive atmospheres, whereas the directive 1999/92/CE formulates minimum requirements for the safety and health protection of workers potentially at risk from explosive atmospheres.…”

Section: Main Current Safety and Technical Regulations Pertinent To Tmentioning

confidence: 99%

“…Hydrogen produced with this process is stored in pressurized gas cylinders and can be used to supply electricity for various farming applications. The use of solar hydrogen power systems can provide a possible option for powering stand-alone greenhouses (Ganguly et al, 2010), which are widespread, especially in the areas with unfavourable climatic conditions (von Zabeltitz, 1999;Baldoin et al, 2008;Giacomelli et al, 2012). Really the storage of solar energy in the form of hydrogen (H2) can be the basis for a totally renewable system, composed by photovoltaic panels in combination with hydrogen produced by electrolysis, H2-storage and fuel cells connected to a ground source heat pump (Kondili and Kaldellis, 2006).…”

Section: Introductionmentioning

confidence: 99%

Hazards assessment and technical actions due to the production of pressured hydrogen within a pilot photovoltaic-electrolyser-fuel cell power system for agricultural equipment

Pascuzzi

Blanco

Anifantis

et al. 2016

J Agricult Engineer

View full text Add to dashboard Cite

A pilot power system formed by photovoltaic panels, alkaline electrolyser and fuel cell stacks was designed and set up to supply the heating system of an experimental greenhouse. The aim of this paper is to analyse the main safety aspects of this power system connected to the management of the pressured hydrogen, such as the explosion limits of the mixture hydrogen-oxygen, the extension of the danger zone, the protection pressure vessels and the system to make unreactive the plant. The electrolyser unit is the core of this plant and from the safety point of view has been equipped with devices able to highlight the malfunctions before they cause damages. Alarm situations are highlighted and the production process is cut off in safe conditions in the event that the operational parameters have an abnormal deviation from the design values. Also the entire power system has been designed so that any failure to its components does not compromise the workers' safety even if the risk analysis is in progress because technical operations are being carried out for enhancing the plant functionality, making it more suitable to the designed task of supplying electrically the greenhouse heating system during cold periods. Some experimental data pertinent to the solar radiation and the corresponding hydrogen production rate are also reported. At present it does not exist a well-established safety reference protocol to design the reliability of these types of power plants and then the assumed safety measures even if related to the achieved pilot installation, can represent an original base of reference to set up guidelines for designing the safety of power plants in the future available for agricultural purposes.

show abstract

Greenhouse Structures

Cited by 9 publications

References 22 publications

Irrigation Water Management in a Mediterranean Greenhouse District: Irrigation Adequacy Assessment

Irrigation Water Management in a Mediterranean Greenhouse District: Irrigation Adequacy Assessment

The perfectly smart greenhouse cover : a simulation study

Hazards assessment and technical actions due to the production of pressured hydrogen within a pilot photovoltaic-electrolyser-fuel cell power system for agricultural equipment

Contact Info

Product

Resources

About