Tag Archives: energy

760–766 E. Kucuktopcu, B. Cemek and P. Banda
Determination of poultry house indoor heating and cooling days using degree-day method
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Determination of poultry house indoor heating and cooling days using degree-day method

E. Kucuktopcu*, B. Cemek and P. Banda

University of Ondokuz Mayis, Faculty of Agriculture, Department of Agricultural Structures and Irrigation, TR 55139 Samsun, Turkey
*Correspondence: erdem.kucuktopcu@omu.edu.tr

Abstract:

In poultry production, degree-day values are used as fundamental design parameters considered among others in determining the extent of heating and cooling of poultry housing. In this study, heating and cooling data values for each of broiler production period were determined using the degree-day method. The total length of the experiment was 123 days which corresponds to 3 growing periods. The inside and outside air temperatures of the poultry house were measured using air temperature data loggers positioned at different points and heights within and outside broiler house. Knowledge of heating and cooling day values is important as it necessitates the provision and maintenance of ideal bird’s production conditions and ensuring the economic viability of the enterprise through optimized energy consumption.

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941–951 O.L. Akangbe and D. Herak
Mechanical behaviour of selected bulk oilseeds under compression loading
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Mechanical behaviour of selected bulk oilseeds under compression loading

O.L. Akangbe and D. Herak*

Czech University of Life Sciences, Faculty of Engineering, Department of Mechanical Engineering, Kamycka 129, Praha 6 – Suchdol, CZ16521 Prague, Czech Republic
*Correspondence: herak@tf.czu.cz

Abstract:

Cold pressing or compressive mechanical expression of oil from bulk oilseeds without thermal treatments or appreciable thermal effects facilitates the preservation of quality in expressed oils and enhances their stability in storage. Mechanical response of bulk oilseeds during cold expression which are vital to equipment design vary with crops and are not completely understood. Mechanical behaviours of bulk seeds of camelina, pumpkin and sesame relevant to cold pressing were investigated at moisture contents of 7.04, 8.60 and 6.06% (d.b.), 80 mm pressing depth and a compressive force of 100 kN, applied uniformly at 10 mm min-1. Deformation varied with incremental force and among crops at peak compression. Deformations in Camelina, Sesame and Pumpkin seeds were 40.2, 41.6 and 50.9 mm at peak compression. Oil point pressures of Sesame, Camelina and Pumpkin seeds were 3.83, 7.49 and 8.83 MPa, respectively. Oil recovery at the applied load was similar in Camelina and Sesame but significantly lower in pumpkin seeds. Volume energy requirement for the expression of oil from camelina, pumpkin and sesame seeds were 2.56, 1.72 and 1.46 MJ m-3, respectively. An assessment of the pressed cake after oil expression revealed that the materials were capable of further deformation under compression.

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477-484 M. Dzikevics, A. Blumberga and D. Blumberga
Conceptual design of experimental solar heat accumulation system with phase change materials
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Conceptual design of experimental solar heat accumulation system with phase change materials

M. Dzikevics*, A. Blumberga and D. Blumberga

Riga Technical University, Faculty of Power and Electrical Engineering, Institute of Energy Systems and Environment, Azenes 12/1, LV1048 Riga, Latvia; *Correspondence: mikelis.dzikevics@rtu.lv

Abstract:

The research on solar heating systems often is faced with choice of carrying out experiments in real systems with changing parameters or to use modelling software with constant parameters but many undefined parameters or assumptions. The design of experimental system for simulating solar heat accumulation is proposed in this paper. The proposed design allows testing of phase change materials which provide higher thermal density compared to water. Results from computational fluid dynamic simulations carried out by other studies have been analysed for implementation into designing of the tank. All of these factors have been taken into account to create a system that resembles real case and can simulate for a long periods of time.

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596-603 D. Marčev, M. Růžička, M. Lukeš and M. Kotek
Energy consumption of commuting from suburban areas
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Energy consumption of commuting from suburban areas

D. Marčev*, M. Růžička, M. Lukeš and M. Kotek

¹University of Life Sciences Prague, Faculty of Engineering, Department of Vehicles ang ground transport, Kamýcká 129, CZ16521 Prague, Czech Republic; *Correspondence: marcev@tf.czu.cz

Abstract:

The process of suburbanization begun half a century later in the Czech Republic in comparison to Western Europe. It has given rise to similar changes in the individual behaviour of potential residents, resulting in different land use and the emergence of new requirements involving technical and transport infrastructures. Many factors that characterize suburban land use, e.g., density of population (households), free access to public facilities, availability of transport modes, etc., are closely associated with energy consumption, specifically in transport. Suburban development affects not only transportation inside expanding suburban municipalities but also their surroundings, e.g., the cumulative effect of traffic intensity increasing on roads radially oriented towards the city centre has been observed in recent years. The construction of manufacturing facilities, logistic and commercial complexes, entertainment centres, etc. continues within the suburban areas and it tends to significantly increase traffic movements (e.g., in tangential directions towards the core of the city). The current capacity of transport infrastructures does not correspond to the increased vehicle intensity (even not only during peak hours) and it does not guarantee an adequate quality for transport operation. The results of performed traffic surveys proved that morning traffic intensity (during peak hours) on the roads (of 2nd. or 3rd. class) leading to the city centre has doubled in the last five years. These results mean that transport energy consumption has increased enormously. Transport energy consumption is higher than usually expected in these cases. The energy consumption (fuel consumption) determined according to a vehicle’s homologation does not take into account the conditions that may affect driving style in a negative manner, e.g., slow driving, traffic congestions road, vertical alignment and tortuous roads. The mean consumption was 9.2 (l 100 km-1) on the selected trail sections –that is 1.66 more than the combined consumption figure presented by car producers. The selected sections make up 54% of the total trail length. This ‘local consumption’ is linked with higher emission production, details are available below. The author compared specific fuel consumption per 100 km and found that real consumption is evidently always higher than the quantities claimed to be correct by car producers in view of mixed modes. The same has been found by, e.g. Marique & Reiter, 2012 and other authors. The conclusions of the research are potentially relevant and should be used in a spatial planning or decision making processes to prevent ‘urban sprawl’ and the accompanying high energy consumption. Suburban development should go hand in hand with the construction of new transport infrastructures and high-quality public transport.

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596-603 D. Marčev, M. Růžička, M. Lukeš and M. Kotek
Energy consumption of commuting from suburban areas
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Energy consumption of commuting from suburban areas

D. Marčev*, M. Růžička, M. Lukeš and M. Kotek

¹University of Life Sciences Prague, Faculty of Engineering, Department of Vehicles ang ground transport, Kamýcká 129, CZ16521 Prague, Czech Republic; *Correspondence: marcev@tf.czu.cz

Abstract:

The process of suburbanization begun half a century later in the Czech Republic in comparison to Western Europe. It has given rise to similar changes in the individual behaviour of potential residents, resulting in different land use and the emergence of new requirements involving technical and transport infrastructures. Many factors that characterize suburban land use, e.g., density of population (households), free access to public facilities, availability of transport modes, etc., are closely associated with energy consumption, specifically in transport. Suburban development affects not only transportation inside expanding suburban municipalities but also their surroundings, e.g., the cumulative effect of traffic intensity increasing on roads radially oriented towards the city centre has been observed in recent years. The construction of manufacturing facilities, logistic and commercial complexes, entertainment centres, etc. continues within the suburban areas and it tends to significantly increase traffic movements (e.g., in tangential directions towards the core of the city). The current capacity of transport infrastructures does not correspond to the increased vehicle intensity (even not only during peak hours) and it does not guarantee an adequate quality for transport operation. The results of performed traffic surveys proved that morning traffic intensity (during peak hours) on the roads (of 2nd. or 3rd. class) leading to the city centre has doubled in the last five years. These results mean that transport energy consumption has increased enormously. Transport energy consumption is higher than usually expected in these cases. The energy consumption (fuel consumption) determined according to a vehicle’s homologation does not take into account the conditions that may affect driving style in a negative manner, e.g., slow driving, traffic congestions road, vertical alignment and tortuous roads. The mean consumption was 9.2 (l 100 km-1) on the selected trail sections –that is 1.66 more than the combined consumption figure presented by car producers. The selected sections make up 54% of the total trail length. This ‘local consumption’ is linked with higher emission production, details are available below. The author compared specific fuel consumption per 100 km and found that real consumption is evidently always higher than the quantities claimed to be correct by car producers in view of mixed modes. The same has been found by, e.g. Marique & Reiter, 2012 and other authors. The conclusions of the research are potentially relevant and should be used in a spatial planning or decision making processes to prevent ‘urban sprawl’ and the accompanying high energy consumption. Suburban development should go hand in hand with the construction of new transport infrastructures and high-quality public transport.

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261-268 M. Rajaniemi, M. Turunen and J. Ahokas
Direct energy consumption and saving possibilities in milk production
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Direct energy consumption and saving possibilities in milk production

M. Rajaniemi, M. Turunen and J. Ahokas*

University of Helsinki, Faculty of Agriculture and Forestry, Department of Agricultural Sciences, PL 28 (Koetilantie 5), 00014 Helsingin yliopisto, Finland; *Correspondence: jukka.ahokas@helsinki.fi

Abstract:

Direct energy consumption in milk production varies largely because of machinery, production systems, working habits and maintenance. There are good possibilities to save energy in milk production. The magnitude of energy savings are in the order of tens of percent, which means that energy saving potential is quite high. Energy saving can be achieved with efficient system and machinery choices. Also adjustments and maintenance have an effect on energy consumption. To save energy the farmers should have means to measure energy and follow energy consumption. There should also be more information of energy saving possibilities and machinery energy consumptions.

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237-244 M. Zajicek, and P. Kic
Heating of large agricultural and industrial buildings
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Heating of large agricultural and industrial buildings

M. Zajicek¹,* and P. Kic²

¹Institute of Information Theory and Automation, The Academy of Science of The Czech Republic, v.v.i.; *Correspondence: zajicek@utia.cas.cz 2Czech University of Life Sciences Prague, Faculty of Engineering, Czech Republic

Abstract:

This paper presents the results of the simulation calculations used in the selection and design of an appropriate method of heating of large buildings for agricultural or industrial purposes. These halls are characterized by a large built-up area, large room height and high consumption of energy for heating. The aim of the simulation calculation was to find a way of heating, which leads to a reduction in energy consumption while maintaining the required thermal comfort of indoor environment. The calculations were performed using the CFD software ANSYS-Fluent. For comparison of variants, a 3D model was used, including a heat source, natural convection and heat transfer through surrounding structures. The results of the thermal comfort of the working environment in the level of people or the growing zone of plants or the storage space for goods were mainly studied. The second area of interior space, especially important in terms of heat losses, is the level of the ceiling. The results of the calculations provide a detailed analysis of the vertical temperature profiles and the effect of the surrounding walls surface temperature on the thermal state of an indoor environment. The created model was verified according to the results of experiments in large buildings equipped with different heating systems. Based on the results of the simulation calculations and according to the results of experimental measurements, radiant heating method seems to be the suitable heating system solution for studied types of buildings.

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603-610 J. Ružbarský, M. Müller and P. Hrabe
Analysis of physical and mechanical properties and of gross calorific value of Jatropha curcas seeds and waste from pressing process
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Analysis of physical and mechanical properties and of gross calorific value of Jatropha curcas seeds and waste from pressing process

J. Ružbarský¹*, M. Müller² and P. Hrabe²

¹Technical University of Košice, Faculty of Manufacturing Technologies, Department of Technological Systems Operation, Štúrova 31, Prešov 08001, Slovak Republic;
*Correspondence: juraj.ruzbarsky@tuke.sk
²Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Science, Kamýcká 129, 16521 Prague, Czech Republic

Abstract:

The  research  was  performed  with  an  aim  to  investigate  physical  and  mechanical properties and a gross calorific value of Jatropha curcas seeds and particular products (waste) of  a  pressing  process.  Sizes  of  seeds,  an  energy  which  is  necessary  for  pressing  an  oil  and  a setting  of  the  gross  calorific  value  were  tested  parameters.  Tests  were  performed  at  Jatropha Curcas seeds of a brown colour (that means gnaw). The pressing process waste amounts up to 80%. The proportion of the kernel mass to the coat mass is 1:0.62. From the research results it follows that the coat mass is 37.60%. The seed coat belongs among interesting material owing to  the  gross  calorific  value.  For pressing  the  whole  seeds  it  is  necessary  of  about  30%  higher energy than for pressing the kernels of Jatropha curcas.

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307-318 A. Jasinskas,, R. Simonavičiūtė, E. Šarauskis, A. Sakalauskasand S. Čekanauskas
Assessment of unconventional bioenergy plant chopping, milling and pelleting quality indicators and physical-mechanical properties
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Assessment of unconventional bioenergy plant chopping, milling and pelleting quality indicators and physical-mechanical properties

A. Jasinskas¹,*, R. Simonavičiūtė¹, E. Šarauskis¹, A. Sakalauskas¹and S. Čekanauskas²

¹Aleksandras Stulginskis University, Faculty of Agricultural Engineering,Institute of Agricultural Engineering and Safety, Kaunas-Akademija,Studentu str. 15A, LT-53361 Kauno r., Lithuania;
*Correspondence: algirdas.jasinskas@asu.lt
²Aleksandras Stulginskis University, Experimental Station, Kaunas-Akademija,LT-53361 Kauno r., Lithuania

Abstract:

This paper provides the research results of techniques for solid biofuel preparation,while usage of chopping (chipping), milling and pressing (pelleting) of the unconventionalbioenergy plants – elephant grass (Miscanthus x giganteus), fibrous hemp (Futura 75) andfibrous nettle. These energy plants were grown in the experimental fields of the Institute ofAgriculture, Aleksandras Stulginskis University and Lithuanian Research Centre forAgriculture and Forestry. It was approved as the methodology for solid biofuel preparation ofunconventional bioenergy plants, and was selected as the technique for plant chopping, milling,pressing, and the technique for determination of plant chaff, mill and pellet quality. There arepresented results of the experimental research. There were determined the unconventionalbioenergy plant stems, chaff and mill chopping quality, in justification of the use of the drumchopping and hummer milling equipment for prepared chaff and mill fractional composition.The quality of stem chaff and mill fineness was defined according to the most widely usedmethodology approved by the EU countries. There were determined physical-mechanicalproperties of these unconventional bioenergy plant chaff, mill and pellets – plant moisturecontent, bulk density, natural slope and failure angles. Key words: elephant grass, hemp, nettle, stems, chaff, mill, pellets, moisture content, bulkdensity, fractional composition.INTRODUCTION

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319-328 S. Kalinauskaitė,, A. Sakalauskas, E. Šarauskis, A. Jasinskasand M. Ahlhaus
Relation of energy content variations of straw to the fraction size, humidity, composition and environmental impact
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Relation of energy content variations of straw to the fraction size, humidity, composition and environmental impact

S. Kalinauskaitė¹,*, A. Sakalauskas¹, E. Šarauskis¹, A. Jasinskas¹and M. Ahlhaus²

¹Aleksandras Stulginskis University, Studentų g. 11, Akademija, Kauno r.LT-53361, Lithuania; *Correspondence: solveiga.kalinauskaite@gmail.com
²Fachhochschule Stralsund, Institut für Regenerative Energie Systeme (IRES),Zur Schwedenschanze 15, 18435 Stralsund, Germany

Abstract:

Biomass is the major source of renewable energy, the use of which is very importantin energy, environment and economical aspects. Biomass enables the replacement of fossilfuels, the importance of biomass usage is related to global warming questions. Biomassmoisture content is one of the main factors affecting straw preparation for the usage cost.In this research the main focus is on straw and different biomass composition and how itinfluences the solid biofuels preparation for usage, paying attention to straw fraction, humidity,composition and finally how it influences the energy and environmental aspects. Testedsamples consist of different composition- raw straw, 100% yellow straw pellets, 100% greystraw pellets, 98% straw pellets with 2% additives, 50% straw and 50% hay pellets, 49% strawand 49% hay pellets with 2% additives, 100% hay pellets, 98% hay pellets with 2% additivesand additionally two samples of straw briquettes with different chop size – (20 mm) and(30 mm and 10 mm). This research pays attention to the main material characteristics –moisture value, ash content, HHV (higher heating value), pyrolysis coke. Research results willhelp to find the best biomass pellet and briquette composition for solid biofuel usage. Duringthe research it was found that the lowest moisture value was 98% hay pellets with 2% CaOadditive – 5.79%. Highest amount of ash value was found in 50% straw and 50% haycomposition pellets – 0.021 g. Highest amount of HHV were tested pellets which consisted of98% hay with 2% CaO additives. Highest amount of pyrolysis coke in organic and dry matterwere in 100% yellow straw tested samples.Achieved results will help to estimate material fraction, humidity and composition on biomasspreparation for conversion steps, following biomass usage energy and environmentrequirements. These research results will help to realise further tasks of agricultural biomassusage in practice.

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