Search results for: energy and exergoeconomic analysis

Authors: Farooq A. Al-Sheikh, Ali Elkamel, William A. Anderson

Abstract:

A fluidized catalytic cracking unit (FCCU) is one of the effective units in many refineries. Modeling and optimization of FCCU were done by many researchers in past decades, but in this research, comparison between post- and oxy-combustion was studied in the regenerator-FCCU. Therefore, a simplified mathematical model was derived by doing mass/heat balances around both reactor and regenerator. A state space analysis was employed to show effects of the flow rates variables such as air, feed, spent catalyst, regenerated catalyst and flue gas on the output variables. The main aim of studying dynamic responses is to figure out the most influencing variables that affect both reactor/regenerator temperatures; also, finding the upper/lower limits of the influencing variables to ensure that temperatures of the reactors and regenerator work within normal operating conditions. Therefore, those values will be used as side constraints in the optimization technique to find appropriate operating regimes. The objective functions were modeled to be maximizing the energy in the reactor while minimizing the energy consumption in the regenerator. In conclusion, an oxy-combustion process can be used instead of a post-combustion one.

Keywords: FCCU modeling, optimization, oxy-combustion, post-combustion

Procedia PDF Downloads 201

Authors: Annisa Ulfah Pristya, Andi Setiawan

Abstract:

Electricity is the primary requirement today's world, including Indonesia. This is because electricity is a source of electrical energy that is flexible to use. Fossil energy sources are the major energy source that is used as a source of energy power plants. Unfortunately, this conversion process impacts on the depletion of fossil fuel reserves and causes an increase in the amount of CO2 in the atmosphere, disrupting health, ozone depletion, and the greenhouse effect. Solutions have been applied are solar cells, ocean wave power, the wind, water, and so forth. However, low efficiency and complicated treatment led to most people and industry in Indonesia still using fossil fuels. Referring to this Fuel Cell was developed. Fuel Cells are electrochemical technology that continuously converts chemical energy into electrical energy for the fuel and oxidizer are the efficiency is considerably higher than the previous natural source of electrical energy, which is 40-60%. However, Fuel Cells still have some weaknesses in terms of the use of an expensive platinum catalyst which is limited and not environmentally friendly. Because of it, required the simultaneous source of electrical energy and environmentally friendly. On the other hand, Indonesia is a rich country in marine sediments and organic content that is never exhausted. Stacking the organic component can be an alternative energy source continued development of fuel cell is A Microbial Fuel Cell. Microbial Fuel Cells (MFC) is a tool that uses bacteria to generate electricity from organic and non-organic compounds. MFC same tools as usual fuel cell composed of an anode, cathode and electrolyte. Its main advantage is the catalyst in the microbial fuel cell is a microorganism and working conditions carried out in neutral solution, low temperatures, and environmentally friendly than previous fuel cells (Chemistry Fuel Cell). However, when compared to Chemistry Fuel Cell, MFC only have an efficiency of 40%. Therefore, the authors provide a solution in the form of Nano-MFC (Nano Microbial Fuel Cell): Utilization of Carbon Nano Tube to Increase Efficiency of Microbial Fuel Cell Power as an Effective, Efficient and Environmentally Friendly Alternative Energy Source. Nano-MFC has the advantage of an effective, high efficiency, cheap and environmental friendly. Related stakeholders that helped are government ministers, especially Energy Minister, the Institute for Research, as well as the industry as a production executive facilitator. strategic steps undertaken to achieve that begin from conduct preliminary research, then lab scale testing, and dissemination and build cooperation with related parties (MOU), conduct last research and its applications in the field, then do the licensing and production of Nano-MFC on an industrial scale and publications to the public.

Keywords: CNT, efficiency, electric, microorganisms, sediment

Procedia PDF Downloads 392

Authors: Anu Soikkelii, Laura Sorri

Abstract:

Finnish national research project, User- and Business-oriented Suburb Renovation Concept (KLIKK), was started in January 2012 and will end in June 2014. The perspective of energy efficiency is emphasised in the project, but also it addresses what improving the energy efficiency of suburban apartment buildings means from the standpoint of architecturally valuable buildings representing different periods. The project will also test the impacts of stricter energy efficiency requirements on renovation projects. The primary goal of the project is to develop a user-oriented, industrial, economic renovation concept for suburban apartment building renovation, extension and construction of additional storeys. The concept will make it possible to change from performance- and cost-based operation to novel service- and user-oriented, site-specifically tailored renovation methods utilizing integrated order and delivery chains.The present project is collaborating with Ministry of the Environment and participating cities in developing a new type of lighter town planning model for suburban renovations and in-fill construction. To support this, the project will simultaneously develop practices for environmental impact assessment tools in renovation and suburban supplementary and in-fill construction.

Keywords: energy efficiency, prefabrication, renovation concept, suburbs, sustainability, user-orientated

Procedia PDF Downloads 322

Authors: Saddam Husain Dhobi, Bikrant Karki

Abstract:

The main objective of this paper is save money, balance ecosystem of the terrestrial organism, control global warming, and enhancing the storage capacity of the battery with requiring weight and thinness by using Cyanobacteria in the battery. To fulfill this purpose of paper we can use different methods: Analysis, Biological, Chemistry, theoretical and Physics with some engineering design. Using this different method, we can produce the special type of battery that has the long life, high storage capacity, and clean environment, save money so on and by using the byproduct of Cyanobacteria i.e. glucose. Cyanobacteria are a special type of bacteria that produces different types of extracellular glucoses and oxygen with the help of little sunlight, water, and carbon dioxide and can survive in freshwater, marine and in the land as well. In this process, O₂ is more in the comparison to plant due to rapid growth rate of Cyanobacteria. The required materials are easily available in this process to produce glucose with the help of Cyanobacteria. Since CO₂, is greenhouse gas that causes the global warming? We can utilize this gas and save our ecological balance and the byproduct (glucose) C₆H₁₂O₆ can be utilized for raw material for the battery where as O₂ escape is utilized by living organism. The glucose produce by Cyanobateria goes on Krebs's Cycle or Citric Acid Cycle, in which glucose is complete, oxidizes and all the available energy from glucose molecule has been release in the form of electron and proton as energy. If we use a suitable anodes and cathodes, we can capture these electrons and protons to produce require electricity current with the help of byproduct of Cyanobacteria. According to "Virginia Tech Bio-battery" and "Sony" 13 enzymes and the air is used to produce nearly 24 electrons from a single glucose unit. In this output power of 0.8 mW/cm, current density of 6 mA/cm, and energy storage density of 596 Ah/kg. This last figure is impressive, at roughly 10 times the energy density of the lithium-ion batteries in your mobile devices. When we use Cyanobacteria in battery, we are able to reduce Carbon dioxide, Stop global warming, and enhancing the storage capacity of battery more than 10 times that of lithium battery, saving money, balancing ecology. In this way, we can produce energy from the Cyanobacteria and use it in battery for different benefits. In addition, due to the mass, size and easy cultivation, they are better to maintain the size of battery. Hence, we can use Cyanobacteria for the battery having suitable size, enhancing the storing capacity of battery, helping the environment, portability and so on.

Keywords: anode, byproduct, cathode, cyanobacteri, glucose, storage capacity

Procedia PDF Downloads 327

Authors: Jaewook Ha, Jin-beak Kim, Seongmin Kim

Abstract:

In order to solve global warming and climate change issues, increased efforts have been devoted towards clean and sustainable energy sources as well as new energy generating devices. Nanogenerator is a device that converts mechanical/thermal energy as produced by small-scale physical change into electricity. Here we propose that nature-leaf surface could be used for preparation of a triboelectric nanogenerator. The nature-leaf surface consists of polydimethylsiloxane microscale pillars and polytetrafluoroethylene nanoparticles. Interaction between the nature-leaf surface and water was studied and the electrical outputs from the motion of single water drop were measured. A 40-μL water drop can generate a peak voltage of 1 V and a peak current of 0.7 μA. This nanogenerator might be used to drive electric devices in the outdoor environments in a sustainable manner.

Keywords: hierarchical surface, lotus-leaf, electrical generator, waterdrop

Procedia PDF Downloads 278

Authors: Gyula I. Tóth, Shaho Abdalla

Abstract:

Even though numerical simulations indeed have a significant precursory/supportive role in exploring the disordered phase displaying no long-range order in pattern formation models, studying the stability properties of this phase and determining the order of the ordered-disordered phase transition in these models necessitate an analytical description of the disordered phase. First, we will present the results of a comprehensive statistical analysis of a large number (1,000-10,000) of numerical simulations in the Swift-Hohenberg model, where the bulk disordered (or amorphous) phase is stable. We will show that the average free energy density (over configurations) converges, while the variance of the energy density vanishes with increasing system size in numerical simulations, which suggest that the disordered phase is a thermodynamic phase (i.e., its properties are independent of the configuration in the macroscopic limit). Furthermore, the structural analysis of this phase in the Fourier space suggests that the phase can be modeled by a colored isotropic Gaussian noise, where any instant of the noise describes a possible configuration. Based on these results, we developed the general mathematical framework of finding a pool of solutions to partial differential equations in the sense of continuous probability measure, which we will present briefly. Applying the general idea to the Swift-Hohenberg model we show, that the amorphous phase can be found, and its properties can be determined analytically. As the general mathematical framework is not restricted to continuum theories, we hope that the proposed methodology will open a new chapter in studying disordered phases.

Keywords: fundamental theory, mathematical physics, continuum models, analytical description

Procedia PDF Downloads 117

Authors: Abdullah Almatouq, Abdulla Abusam, Hussain Hussain, Mishari Khajah, Hussain Abdullah, Rashed Al-Yaseen, Mariam Al-Jumaa, Farah Al-Ajeel, Mohammad Aljassam

Abstract:

Due to the high demand for energy from unsustainable resources in Kuwait, the Kuwaiti government has focused recently on using sustainable resources for energy, such as solar and wind energy. In addition, sludge which is generated as a by-product of physical, chemical, and biological processes during wastewater treatment, can be used as a substrate to generate energy through anaerobic digestion. Kuwait’s wastewater treatment plants produce more than 1.7 million m3 of sludge per year, and this volume is accumulated in the treatment plants without any treatment. Therefore, a pilot-scale (3 m3) two-stage anaerobic digester was constructed in one of the largest treatment plants in Kuwait. The reactor was operated in batch mode, and the hydraulic retention time varied between 14 – 27 days. The main of this study is to evaluate the technical feasibility of a two-stage anaerobic digester for sludge treatability and energy generation in Kuwait. The anaerobic digester achieved a total biogas production of 37 m3, and the highest value of daily biogas production was 0.4 m3/day. The methane content ranged between 50 % and 66 %, and the other gases were as follows: CO2 20 %, H2S 13 %, and 1 % O2. The generated biogas was used on-site for cooking and lighting. In some batches, low C/N was noticed, and that lead to maintaining the concentration of CH4 between 50%-55%. In conclusion, an anaerobic digester is an environmentally friendly technology that can be applied in Kuwait, and the obtained results support the scale-up of the process in all the treatment plants.

Keywords: wastewater, metahne, biogas production potential, anaerobic digestion

Procedia PDF Downloads 91

Authors: Diego A. Romero Espinosa

Abstract:

Thermal simulations are used to evaluate comfort and energy consumption of buildings. However, the performance of different urban forms cannot be assessed precisely if an environmental control system and user schedules are considered. The outcome of such analysis would lead to conclusions that combine the building use, operation, services, envelope, orientation and density of the urban fabric. The influence of these factors varies during the life cycle of a building. The orientation, as well as the surroundings, can be considered a constant during the lifetime of a building. The structure impacts the thermal inertia and has the largest lifespan of all the building components. On the other hand, the building envelope is the most frequent renovated component of a building since it has a great impact on energy performance and comfort. Building services have a shorter lifespan and are replaced regularly. With the purpose of addressing the performance, an urban form, a specific orientation, and density, a thermal simulation method were developed. The solar irradiation is taken into consideration depending on the outdoor temperature. Incoming irradiation at low temperatures has a positive impact increasing the indoor temperature. Consequently, overheating would be the combination of high outdoor temperature and high irradiation at the façade. On this basis, the indoor temperature is simulated for a specific orientation of the evaluated urban form. Thermal inertia and building envelope performance are considered additionally as the materiality of the building. The results of different thermal zones are summarized using the 'Degree day method' for cooling and heating. During the early phase of a design process for a project, such as Masterplan, conclusions regarding urban form, density and materiality can be drawn by means of this analysis.

Keywords: building envelope, density, masterplanning, urban form

Procedia PDF Downloads 131

Authors: Vinh Duy Cao, Carlos Salas-Bringas, Anna M. Szczotok, Marianne Hiorth, Anna-Lena Kjøniksen

Abstract:

The increasing cost of energy supply for the purposes of heating and cooling creates a demand for more energy efficient buildings. Improved construction techniques and enhanced material technology can greatly reduce the energy consumption needed for the buildings. Microencapsulated phase change materials (MPCM) suspensions utilized as heat transfer fluids for energy storage and heat transfer applications provide promising potential solutions. A full understanding of the flow and thermal characteristics of microcapsule suspensions is needed to optimize the design of energy storage systems, in order to reduce the capital cost, system size, and energy consumption. The MPCM suspensions exhibited pseudoplastic and thixotropic behaviour, and significantly improved the thermal performance of the suspensions. Three different models were used to characterize the thixotropic behaviour of the MPCM suspensions: the second-order structural, kinetic model was found to give a better fit to the experimental data than the Weltman and Figoni-Shoemaker models. For all samples, the initial shear stress increased, and the breakdown rate accelerated significantly with increasing concentration. The thermal performance and rheological properties, especially the selection of rheological models, will be useful for developing the applications of microcapsules as heat transfer fluids in thermal energy storage system such as calculation of an optimum MPCM concentration, pumping power requirement, and specific power consumption. The effect of temperature on the shear thinning properties of the samples suggests that some of the phase change material is located outside the capsules, and contributes to agglomeration of the samples.

Keywords: latent heat, microencapsulated phase change materials, pseudoplastic, suspension, thixotropic behaviour

Procedia PDF Downloads 252

Authors: Bahiru Tsegaye, Chandrajit Balomajumder, Partha Roy

Abstract:

The limited supply and related negative environmental consequence of fossil fuels are driving researcher for finding sustainable sources of energy. Lignocellulose biomass like sorghum straw is considered as among cheap, renewable and abundantly available sources of energy. However, lignocellulose biomass conversion to bioenergy like bioethanol is hindered due to the reluctant nature of lignin in the biomass. Therefore, removal of lignin is a vital step for lignocellulose conversion to renewable energy. The aim of this study is to optimize microwave pretreatment conditions using design expert software to remove lignin and to release maximum possible polysaccharides from sorghum straw for efficient hydrolysis and fermentation process. Sodium hydroxide concentration between 0.5-1.5%, v/v, pretreatment time from 5-25 minutes and pretreatment temperature from 120-2000C were considered to depolymerize sorghum straw. The effect of pretreatment was studied by analyzing the compositional changes before and after pretreatments following renewable energy laboratory procedure. Analysis of variance (ANOVA) was used to test the significance of the model used for optimization. About 32.8%-48.27% of hemicellulose solubilization, 53% -82.62% of cellulose release, and 49.25% to 78.29% lignin solubilization were observed during microwave pretreatment. Pretreatment for 10 minutes with alkali concentration of 1.5% and temperature of 1400C released maximum cellulose and lignin. At this optimal condition, maximum of 82.62% of cellulose release and 78.29% of lignin removal was achieved. Sorghum straw at optimal pretreatment condition was subjected to enzymatic hydrolysis and fermentation. The efficiency of hydrolysis was measured by analyzing reducing sugars by 3, 5 dinitrisylicylic acid method. Reducing sugars of about 619 mg/g of sorghum straw were obtained after enzymatic hydrolysis. This study showed a significant amount of lignin removal and cellulose release at optimal condition. This enhances the yield of reducing sugars as well as ethanol yield. The study demonstrates the potential of microwave pretreatments for enhancing bioethanol yield from sorghum straw.

Keywords: cellulose, hydrolysis, lignocellulose, optimization

Procedia PDF Downloads 254

Authors: Ryan B. Escorial, Elmer A. Maravillas, Chris Jordan G. Aliac

Abstract:

This study presents a small-scale water pumping system utilizing a fuzzy logic inference system attached to a renewable energy source. The fuzzy logic controller was designed and simulated in MATLAB fuzzy logic toolbox to examine the properties and characteristics of the input and output variables. The result of the simulation was implemented in a microcontroller, together with sensors, modules, and photovoltaic cells. The study used a grand rapid variety of lettuce, organic substrates, and foliar for observation of the capability of the device to irrigate crops. Two plant boxes intended for manual and automated irrigation were prepared with each box having 48 heads of lettuce. The observation of the system took 22-31 days, which is one harvest period of the crop. Results showed a 22.55% increase in agricultural productivity compared to manual irrigation. Aside from reducing human effort, and time, the smart irrigation system could help lessen some of the shortcomings of manual irrigations. It could facilitate the economical utilization of water, reducing consumption by 25%. The use of renewable energy could also help farmers reduce the cost of production by minimizing the use of diesel and gasoline.

Keywords: fuzzy logic, intelligent system, precision agriculture, renewable energy

Procedia PDF Downloads 111

Authors: Muhammad Gillfran Samual, Rinaldy Dalimi, Fauzan Hanif Jufri, Budi Sudiarto, Ismi Rosyiana Fitri

Abstract:

Solar energy is increasingly recognized as an important future energy source due to its abundant availability and renewable nature. However, the intermittent nature of solar energy can cause fluctuations in the electricity produced, making it difficult to guarantee a stable and reliable electricity supply. One solution that can be implemented is to use batteries in a photovoltaic solar power plant system with a Moving Average control algorithm, which can help smooth and reduce fluctuations in solar power output power. The parameter that can be adjusted in the Moving Average algorithm is the window size or the arithmetic average width of the photovoltaic output power over time. This research evaluates the effect of a change of window size parameter in the Moving Average algorithm on the resulting smoothed photovoltaic output power and the technical effects on batteries, i.e., power and energy usage. Based on the evaluation, it is found that the increase of window size parameter will slow down the response of photovoltaic output power to changes in irradiation and increase the smoothing quality of the intermittent photovoltaic output power. In addition, increasing the window size will reduce the maximum power received on the load side, and the amount of energy used by the battery during the power smoothing process will increase, which, in turn, increases the required battery capacity.

Keywords: battery, intermittent, moving average, photovoltaic, power smoothing

Procedia PDF Downloads 32

Authors: Paula Marín, Mohammad Saffari, Alvaro de Gracia, Luisa F. Cabeza, Svetlana Ushak

Abstract:

Climate control represents an important issue when referring to energy consumption of buildings and associated expenses, both in installation or operation periods. The climate control of a building relies on several factors. Among them, localization, orientation, architectural elements, sources of energy used, are considered. In order to study the thermal behaviour of a building set up, the present study proposes the use of energy simulation program Energy Plus. In recent years, energy simulation programs have become important tools for evaluation of thermal/energy performance of buildings and facilities. Besides, the need to find new forms of passive conditioning in buildings for energy saving is a critical component. The use of phase change materials (PCMs) for heat storage applications has grown in importance due to its high efficiency. Therefore, the climatic conditions of Northern Chile: high solar radiation and extreme temperature fluctuations ranging from -10°C to 30°C (Calama city), low index of cloudy days during the year are appropriate to take advantage of solar energy and use passive systems in buildings. Also, the extensive mining activities in northern Chile encourage the use of large numbers of containers to harbour workers during shifts. These containers are constructed with lightweight construction systems, requiring heating during night and cooling during day, increasing the HVAC electricity consumption. The use of PCM can improve thermal comfort and reduce the energy consumption. The objective of this study was to evaluate the thermal and energy performance of containers of 2.5×2.5×2.5 m3, located in four cities of Chile: Antofagasta, Calama, Santiago, and Concepción. Lightweight envelopes, typically used in these building prototypes, were evaluated considering a container without PCM inclusion as the reference building and another container with PCM-enhanced envelopes as a test case, both of which have a door and a window in the same wall, orientated in two directions: North and South. To see the thermal response of these containers in different seasons, the simulations were performed considering a period of one year. The results show that higher energy savings for the four cities studied are obtained when the distribution of door and window in the container is in the north direction because of higher solar radiation incidence. The comparison of HVAC consumption and energy savings in % for north direction of door and window are summarised. Simulation results show that in the city of Antofagasta 47% of heating energy could be saved and in the cities of Calama and Concepción the biggest savings in terms of cooling could be achieved since PCM reduces almost all the cooling demand. Currently, based on simulation results, four containers have been constructed and sized with the same structural characteristics carried out in simulations, that are, containers with/without PCM, with door and window in one wall. Two of these containers will be placed in Antofagasta and two containers in a copper mine near to Calama, all of them will be monitored for a period of one year. The simulation results will be validated with experimental measurements and will be reported in the future.

Keywords: energy saving, lightweight construction, PCM, simulation

Procedia PDF Downloads 266

Authors: Sh. Heidari, A. J. Andrews, A. Oberoi

Abstract:

Electrochemical storage of hydrogen in activated carbon electrodes as part of a reversible fuel cell offers a potentially attractive option for storing surplus electrical energy from inherently variable solar and wind energy resources. Such a system – which we have called a proton flow battery – promises to have a roundtrip energy efficiency comparable to lithium ion batteries, while having higher gravimetric and volumetric energy densities. In this paper, a theoretical model is presented of the process of H+ ion (proton) conduction through an acid electrolyte into a highly porous activated carbon electrode where it is neutralised and absorbed on the inner surfaces of pores. A Butler-Volmer type equation relates the rate of adsorption to the potential difference between the activated carbon surface and the electrolyte. This model for the hydrogen storage electrode is then incorporated into a more general computer model based on MATLAB software of the entire electrochemical cell including the oxygen electrode. Hence a theoretical voltage-current curve is generated for given input parameters for a particular activated carbon electrode. It is shown that theoretical VI curves produced by the model can be fitted accurately to experimental data from an actual electrochemical cell with the same characteristics. By obtaining the best-fit values of input parameters, such as the exchange current density and charge transfer coefficient for the hydrogen adsorption reaction, an improved understanding of the adsorption reaction is obtained. This new model will assist in designing improved proton flow batteries for storing solar and wind energy.

Keywords: electrochemical hydrogen storage, proton flow battery, butler-volmer equation, activated carbon

Procedia PDF Downloads 487

Authors: Anja Gräff, Stefan Holzer, Manfred Höld, Jörn Stumpenhausen, Heinz Bernhardt

Abstract:

In view of the increasing quantity of 'green energy' from renewable raw materials and photovoltaic facilities, it is quite conceivable that power supply variations may occur, so that constantly working machines like automatic milking systems (AMS) may break down temporarily. The usage of farm-made energy is steadily increasing in order to keep energy costs as low as possible. As a result, power cuts are likely to happen more frequently. Current work in the framework of the project 'stable 4.0' focuses on possible stress reactions by simulating power cuts up to four hours in dairy farms. Based on heart activity it should be found out whether stress on dairy cows increases under these circumstances. In order to simulate a power cut, 12 random cows out of 2 herds were not admitted to the AMS for at least two hours on three consecutive days. The heart rates of the cows were measured and the collected data evaluated with HRV Program Kubios Version 2.1 on the basis of eight parameters (HR, RMSSD, pNN50, SD1, SD2, LF, HF and LF/HF). Furthermore, stress reactions were examined closely via video analysis, milk yield, ruminant activity, pedometer and measurements of cortisol metabolites. Concluding it turned out, that during the test only some animals were suffering from minor stress symptoms, when they tried to get into the AMS at their regular milking time, but couldn´t be milked because the system was manipulated. However, the stress level during a regular “time-dependent milking rejection” was just as high. So the study comes to the conclusion, that the low psychological stress level in the case of a 2-4 hours failure of an AMS does not have any impact on animal welfare and health.

Keywords: dairy cow, heart activity, power cut, stable 4.0

Procedia PDF Downloads 301

Authors: Ana Paula Esteves, Diego S. Caetano, Louise L. B. Lomardo

Abstract:

This paper presents an approach to the performance of the natural lighting, when the use of appropriated solar lighting systems on the roof is applied in cultural buildings such as museums and foundations. The roofs, as a part of contact between the building and the external environment, require special attention in projects that aim at energy efficiency, being an important element for the capture of natural light in greater quantity, but also for being the most important point of generation of photovoltaic solar energy, even semitransparent, allowing the partial passage of light. Transparent elements in roofs, as well as superior protection of the building, can also play other roles, such as: meeting the needs of natural light for the accomplishment of the internal tasks, attending to the visual comfort; to bring benefits to the human perception and about the interior experience in a building. When these resources are well dimensioned, they also contribute to the energy efficiency and consequent character of sustainability of the building. Therefore, when properly designed and executed, a roof light system can bring higher quality natural light to the interior of the building, which is related to the human health and well-being dimension. Furthermore, it can meet the technologic, economic and environmental yearnings, making possible the more efficient use of that primordial resource, which is the light of the Sun. The article presents the analysis of buildings that used zenith light systems in search of better lighting performance in museums and foundations: the Solomon R. Guggenheim Museum in the United States, the Iberê Camargo Foundation in Brazil, the Museum of Fine Arts in Castellón in Spain and the Pinacoteca of São Paulo.

Keywords: natural lighting, roof lighting systems, natural lighting in museums, comfort lighting

Procedia PDF Downloads 194

Authors: Vera Varazashvili, Murman Tsarakhov, Tamar Mirianashvili, Teimuraz Pavlenishvili, Tengiz Machaladze, Mzia Khundadze

Abstract:

Standard Gibbs energy of formation ΔGfor(298.15) of lanthanide-iron double oxides of garnet-type crystal structure R3Fe5O12 - RIG (R – are rare earth ions) from initial oxides are evaluated. The calculation is based on the data of standard entropies S298.15 and standard enthalpies ΔH298.15 of formation of compounds which are involved in the process of garnets synthesis. Gibbs energy of formation is presented as temperature function ΔGfor(T) for the range 300-1600K. The necessary starting thermodynamic data were obtained from calorimetric study of heat capacity – temperature functions and by using the semi-empirical method for calculation of ΔH298.15 of formation. Thermodynamic functions for standard temperature – enthalpy, entropy and Gibbs energy - are recommended as reference data for technological evaluations. Through the isostructural series of rare earth-iron garnets the correlation between thermodynamic properties and characteristics of lanthanide ions are elucidated.

Keywords: calorimetry, entropy, enthalpy, heat capacity, gibbs energy of formation, rare earth iron garnets

Procedia PDF Downloads 368

Authors: Ashkan Mirzay Fashami

Abstract:

This study examines the effects of auditor switch, auditee’s industry, and auditee’s location on audit fees in Australia. It uses fee data of Australian Securities Exchange 500 companies, considering all industry classifications throughout the country from 2006 until 2016. Main findings show that auditor switch does not affect audit fees. However, auditee’s industry affects audit fees. This effect occurs in information technology, financials, energy, and materials sectors among the top 500 companies. Financials, energy, and materials sectors face a fee rise, whereas information technology has a fee cut. The extent of fee changes is different among various industries, wherein the financial sector has the highest increase. Further, auditee’s location affects audit fees. Top 500 companies in Hobart, Perth, and Brisbane face a fee reduction, wherein the highest cut is in Hobart. Further analysis suggests that the Australian audit market is being increasingly concentrated in the hands of the Big Four audit firms.

Keywords: audit, auditor switch, Australia, fee, low-balling

Procedia PDF Downloads 127

Authors: Faisal Mahroogi, Mahmoud Bady, Yaser H. Alahmadi, Ahmed Alsisi, Sunny Narayan, Muhammad Usman Kaisan

Abstract:

The Kingdom of Saudi Arabia established Saudi Vision 2030, an initiative of the government with the goal of promoting more socioeconomic as well as cultural diversity. The kingdom, which is dedicated to sustainable development and clean energy, uses cutting-edge approaches to address energy-related issues, including the circular carbon economy (CCE) and a more varied energy mix. In order for Saudi Arabia to achieve its Vision 2030 goal of having a net zero future by 2060, sustainability is essential. By addressing the energy and climate issues of the modern world with responsibility and innovation, Vision 2030 is turning into a global role model for the transition to a sustainable future. As per the Ambitions of the National Environment Strategy of the Saudi Ministry of Environment, Agriculture, and Water (MEWA), raising environmental compliance across all sectors and reducing pollution and adverse environmental impacts are critical focus areas. As a result, the current study presents an experimental analysis of the performance and exhaust emissions of a diesel engine running mostly on waste cooking oil (WCO). A one-cylinder direct-injection diesel engine with constant speed and natural aspiration is the engine type utilized. Research was done on how the engine performed and emission parameters when fueled with a mixture of 10% butanol, 10% diesel, 10% WCO, and 10% diethyl ether (D70B10W10DD10). The study's findings demonstrated that engine emissions of nitrogen oxides (NOX) and carbon monoxide (CO) varied significantly depending on the load being applied. The brake thermal efficiency, cylinder pressure, and the brake power of the engine were all impacted by load change.

Keywords: ICE, waste cooking oil, fuel additives, butanol, combustion, emission characteristics

Procedia PDF Downloads 21

Authors: Angel Fabian Mijangos, Jaime Alvarez Quintana

Abstract:

Waste heat occurs in many areas of daily life because world’s energy consumption is inefficient. In general, generating 1 watt of power requires about 3 watt of energy input and involves dumping into the environment the equivalent of about 2 watts of power in the form of heat. Therefore, an attractive and sustainable solution to the energy problem would be the development of highly efficient thermoelectric devices which could help to recover this waste heat. This work presents the influence on the thermoelectric properties of metallic, semiconducting, and dielectric nanoparticles added into the grain boundaries of polycrystalline antimony (Sb) and bismuth (Bi) matrixes in order to obtain p- and n-type thermoelectric materials, respectively, by hot pressing methods. Results show that thermoelectric properties are significantly affected by the electrical and thermal nature as well as concentration of nanoparticles. Nevertheless, by optimizing the amount of the nanoparticles on the grain boundaries, an oscillatory behavior in ZT as function of the concentration of the nanoscale constituents is present. This effect is due to energy filtering mechanism which module the quantity of charge transport in the system and affects thermoelectric properties. Accordingly, a ZTmax can be accomplished through the addition of the appropriate amount of nanoparticles into the grain boundaries region. In this case, till three orders of amelioration on ZT is reached in both systems compared with the reference sample of each one. This approach paves the way to pursuit high performance thermoelectric materials in a simple way and opens a new route towards the enhancement of the thermoelectric figure of merit.

Keywords: energy filtering, grain boundaries, thermoelectric, nanostructured materials

Procedia PDF Downloads 242

Authors: Ahmad Idris, O.A. Uche, Ado Y Abdulfatah

Abstract:

Lateritic soils are found in abundance and are the most common types of soils used in construction of roads and embankments in Nigeria. Strength properties of the soils depend on the amount of compaction applied and the amount of water available in the soil at the time of compaction. In this study, the influence of the compactive effort and that of the amount of water in the soil in the determination of the shear strength properties of lateritic soil was investigated. Lateritic soil sample was collected from an existing borrow pit in Kano, Nigeria and its basic characteristics were determined and the soil was classified according to AASHTO classification method. The soil was then compacted under various compactive efforts and at wide range of moisture contents. The maximum dry density (MDD) and optimum moisture content (OMC) at each compactive effort was determined. Unconfined undrained triaxial test was carried out to determine the shear strength properties of the soil under various conditions of moisture and energy. Preliminary results obtained indicated that the soil is an A-7-5 soil. The final results obtained shows that as the compaction energy is increased, both the cohesion and friction angle increased irrespective of the moisture content used in the compaction. However, when the amount of water in the soil was increased and compaction effort kept constant, only the cohesion of the soil increases while the friction angle shows no any pattern of variation. It was also found that the highest values for cohesion and friction angle were obtained when the soil was compacted at the highest energy and at OMC.

Keywords: laterite, OMC, compaction energy, moisture content

Procedia PDF Downloads 387

Authors: A. Moualdia, D. J. Boudana, O. Bouchhida, A. Medjber

Abstract:

Wind energy has many advantages, it does not pollute and it is an inexhaustible source. However, the cost of this energy is still too high to compete with traditional fossil fuels, especially on sites less windy. The performance of a wind turbine depends on three parameters: the power of wind, the power curve of the turbine and the generator's ability to respond to wind fluctuations. This paper presents a control chain conversion based on a double-fed asynchronous machine and flow-oriented. The supply system comprises of two identical converters, one connected to the rotor and the other one connected to the network via a filter. The architecture of the device is up by three commands are necessary for the operation of the turbine control extraction of maximum power of the wind to control itself (MPPT) control of the rotor side converter controlling the electromagnetic torque and stator reactive power and control of the grid side converter by controlling the DC bus voltage and active power and reactive power exchanged with the network. The proposed control has been validated in both modes of operation of the three-bladed wind 7.5 kW, using Matlab/Simulink. The results of simulation control technology study provide good dynamic performance and static.

Keywords: D.F.I.G, variable wind speed, hypersynchrone, energy quality, hyposynchrone

Procedia PDF Downloads 357

Authors: Abhipsa Mohanty, Harit Jha

Abstract:

The world's energy demands are continuing to rise, resulting in a worldwide energy crisis and environmental pollution. Because of finite, declining supply and environmental damage, reliance on fossil fuels is unsustainable. As a result, experts are concentrating on alternative, renewable, and carbon-free energy sources. Energy sources that are both environmentally and economically sustainable are required. Microbial fuel cells (MFCs) have recently received a lot of attention due to their low operating temperatures and ability to use a variety of biodegradable substrates as fuel. There are single-chamber MFCs as well as traditional MFCs with anode and cathode compartments. Bioelectricity is produced when microorganisms actively catabolize substrate. MFCs can be used as a power source in small devices like biosensors. Understanding of its components, microbiological processes, limiting variables, and construction designs in MFC systems must be simplified, and large-scale systems must be developed for them to be cost-effective as well as increase electricity production. The purpose of this research was to review current microbiology knowledge in the field of electricity. The manufacturing process, the materials, and procedures utilized to construct the technology, as well as the applications of MFC technology, are all covered.

Keywords: bio-electricity, exoelectrogenic bacteria, microbial fuel cells, soil microorganisms

Procedia PDF Downloads 79

Authors: Shehu, B., Muhammad, B. F., Madigawa, I. L., H. A. Alkali

Abstract:

The study was conducted to assess heifer camel behavior and live weight changes on native range supplemented with different energy levels. A total of nine camels aged between 2 and 3 years were randomly allotted into three groups and supplemented with 3400, 3600 and 3800 Kcal and designated A, B and C, respectively. The data obtained was analyzed for variance in a Completely Randomized Design. The heifers utilized average of 371.70 min/day (64% of daylight time) browsing on native pasture and 2.30 min/day (6%) sand bathing. A significantly higher mean time was spent by heifers on browsing Leptadenia hastata (P<0.001), Dichrostachys cinerea (P<0.01), Acacia nilotica (P<0.001) and Ziziphus spina-christi (P<0.05) in early dry season (January). No significant difference was recorded on browsing time on Tamarindus indica, Adansonia digitata, Piliostigma reticulatum, Parkia biglobosaand Azadirachta indica. No significant (P<0.05) liveweight change was recorded on she-camels due to the three energy levels. It was concluded that nutritive browse species in the study area could meet camel nutrient requirements including energy. Further research on effect of period on camel nutrients requirement in different physiological conditions is recommended.

Keywords: heifer, camel, grazing, pasture

Procedia PDF Downloads 531

Authors: H. Nejadriahi

Abstract:

A growing demand for sustainability makes sustainability as one of the significant debates of nowadays. Energy saving is one of the main criteria to be considered in the context of sustainability. Reducing energy use in buildings is one of the most important ways to reduce humans’ overall environmental impact. Taking this into consideration, study of different design strategies, which can assist in reducing energy use and subsequently improving the sustainability level of today's buildings would be an essential task. The sustainability level of a building is highly affected by the sustainability performance of its components. One of the main building components, which can have a great impact on energy saving and sustainability level of the building, is its facade. The aim of this study is to investigate on the role of facade in sustainability enhancement of the contemporary buildings of Iran. In this study, the concept of sustainability in architecture, the building facades, and their relationship to sustainability are explained briefly. Following that, a number of contemporary Iranian buildings are discussed and analyzed in terms of different design strategies used in their facades in accordance to the sustainability concepts. The methods used in this study are descriptive and analytic. The results of this paper would assist in generating a wider vision and a source of inspiration for the current designers to design and create environmental and sustainable buildings for the future.

Keywords: building facade, contemporary buildings, Iran, sustainability

Procedia PDF Downloads 314

Authors: Oluseyi O. Ajayi, Ohiose D. Ohijeagbon, Mercy Ogbonnaya, Ameh Attabo

Abstract:

The study assessed the potential and economic viability of stand-alone wind systems for embedded generation, taking into account its benefits to small off-grid rural communities at 40 meteorological sites in Nigeria. A specific electric load profile was developed to accommodate communities consisting of 200 homes, a school and a community health centre. This load profile was incorporated within the distributed generation analysis producing energy in the MW range, while optimally meeting daily load demand for the rural communities. Twenty-four years (1987 to 2010) of wind speed data at a height of 10m utilized for the study were sourced from the Nigeria Meteorological Department, Oshodi. The HOMER® software optimizing tool was engaged for the feasibility study and design. Each site was suited to 3MW wind turbines in sets of five, thus 15MW was designed for each site. This design configuration was adopted in order to easily compare the distributed generation system amongst the sites to determine their relative economic viability in terms of life cycle cost, as well as levelised cost of producing energy. A net present value was estimated in terms of life cycle cost for 25 of the 40 meteorological sites. On the other hand, the remaining sites yielded a net present cost; meaning the installations at these locations were not economically viable when utilizing the present tariff regime for embedded generation in Nigeria.

Keywords: wind speed, wind power, distributed generation, cost per kilowatt-hour, clean energy, Nigeria

Procedia PDF Downloads 384

Authors: Gulmira Kenenbay, Urishbay Chomanov, Aruzhan Shoman, Rabiga Kassimbek

Abstract:

The main task of the meat-processing industry is the production of meat products as the main source of animal protein, ensuring the vital activity of the human body, in the required volumes, high quality, diverse assortment. Providing the population with high-quality food products what are biologically full, balanced in composition of basic nutrients and enriched by targeted physiologically active components, is one of the highest priority scientific and technical problems to be solved. In this regard, the formulation of a new brine from sprouted wheat for meat delicacies from horse meat, beef and pork has been developed. The new brine contains flavored aromatic ingredients, juice of the germinated wheat and vegetable juice. The viscosity of meat of horse meat, beef and pork were studied during massaging. Thermodynamic indices, water activity and binding energy of horse meat, beef and pork with application of new brine are investigated. A recipe for meat products with vegetable additives has been developed. Organoleptic evaluation of meat products was carried out. Physicochemical parameters of meat products with vegetable additives are carried out. Analysis of the obtained data shows that the values of the index aw (water activity) and the binding energy of moisture in the experimental samples of meat products are higher than in the control samples. It has been established by investigations that with increasing water activity and the binding energy of moisture, the tenderness of ready meat delicacies increases with the use of a new brine.

Keywords: compounding, functional products, delicatessen products, brine, vegetable additives

Procedia PDF Downloads 166

Authors: Rit M., Girard R., Villot J., Thorel M.

Abstract:

In a scenario of extensive residential housing renovation, stakeholders need models that support decision-making through a deep understanding of the existing building stock and accurate energy demand simulations. To address this need, we have modified an optimization model using open data that enables the study of renovation strategies at both territorial and national scales. This approach provides (1) a definition of a strategy to simplify decision trees from theoretical combinations, (2) input to decision makers on real-world renovation constraints, (3) more reliable identification of energy-saving measures (changes in technology or behaviour), and (4) discrepancies between currently planned and actually achieved strategies. The main contribution of the studies described in this document is the geographic scale: all residential buildings in the areas of interest were modeled and simulated using national data (geometries and attributes). These buildings were then renovated, when necessary, in accordance with the environmental objectives, taking into account the constraints applicable to each territory (number of renovations per year) or at the national level (renovation of thermal deficiencies (Energy Performance Certificates F&G)). This differs from traditional approaches that focus only on a few buildings or archetypes. This model can also be used to analyze the evolution of a building stock as a whole, as it can take into account both the construction of new buildings and their demolition or sale. Using specific case studies of French territories, this paper highlights a significant discrepancy between the strategies currently advocated by decision-makers and those proposed by our optimization model. This discrepancy is particularly evident in critical metrics such as the relationship between the number of renovations per year and achievable climate targets or the financial support currently available to households and the remaining costs. In addition, users are free to seek optimizations for their building stock across a range of different metrics (e.g., financial, energy, environmental, or life cycle analysis). These results are a clear call to re-evaluate existing renovation strategies and take a more nuanced and customized approach. As the climate crisis moves inexorably forward, harnessing the potential of advanced technologies and data-driven methodologies is imperative.

Keywords: residential housing renovation, MILP, energy demand simulations, data-driven methodology

Procedia PDF Downloads 53

Authors: Daniela N. Correa-Llantén, Sebastián A. Muñoz-Ibacache, Mathilde Maire, Jenny M. Blamey

Abstract:

The biosynthesis of nanoparticles by microorganisms, on the contrary to chemical synthesis, is an environmentally-friendly process which has low energy requirements. In this investigation, we used the microorganism Geobacillus wiegelii, strain GWE1, an aerobic thermophile belonging to genus Geobacillus, isolated from a drying oven. This microorganism has the ability to reduce selenite evidenced by the change of color from colorless to red in the culture. Elemental analysis and composition of the particles were verified using transmission electron microscopy and energy-dispersive X-ray analysis. The nanoparticles have a defined spherical shape and a selenium elemental state. Previous experiments showed that the presence of the whole microorganism for the reduction of selenite was not necessary. The results strongly suggested that an intracellular NADPH/NADH-dependent reductase mediates selenium nanoparticles synthesis under aerobic conditions. The enzyme was purified and identified by mass spectroscopy MALDI-TOF TOF technique. The enzyme is a 1-pyrroline-5-carboxylate dehydrogenase. Histograms of nanoparticles sizes were obtained. Size distribution ranged from 40-160 nm, where 70% of nanoparticles have less than 100 nm in size. Spectroscopic analysis showed that the nanoparticles are composed of elemental selenium. To analyse the effect of pH in size and morphology of nanoparticles, the synthesis of them was carried out at different pHs (4.0, 5.0, 6.0, 7.0, 8.0). For thermostability studies samples were incubated at different temperatures (60, 80 and 100 ºC) for 1 h and 3 h. The size of all nanoparticles was less than 100 nm at pH 4.0; over 50% of nanoparticles have less than 100 nm at pH 5.0; at pH 6.0 and 8.0 over 90% of nanoparticles have less than 100 nm in size. At neutral pH (7.0) nanoparticles reach a size around 120 nm and only 20% of them were less than 100 nm. When looking at temperature effect, nanoparticles did not show a significant difference in size when they were incubated between 0 and 3 h at 60 ºC. Meanwhile at 80 °C the nanoparticles suspension lost its homogeneity. A change in size was observed from 0 h of incubation at 80ºC, observing a size range between 40-160 nm, with 20% of them over 100 nm. Meanwhile after 3 h of incubation at size range changed to 60-180 nm with 50% of them over 100 nm. At 100 °C the nanoparticles aggregate forming nanorod structures. In conclusion, these results indicate that is possible to modulate size and shape of biologically synthesized nanoparticles by modulating pH and temperature.

Keywords: genus Geobacillus, NADPH/NADH-dependent reductase, selenium nanoparticles, biosynthesis

Procedia PDF Downloads 300

Authors: Majid Ali, Xinfang Jin, Victor Eniola, Henning Hoene

Abstract:

The performance of proton exchange membrane (PEM) fuel cells is sensitive to several factors, including power fluctuations, hydrogen utilization, and the quality orientation of the fuel cell stack. In this study, we investigate the impact of these factors on the performance of a PEM fuel cell. We start by analyzing the power fluctuations that are typical in renewable energy systems and their effects on the 50 Watt fuel cell's performance. Next, we examine the hydrogen utilization rate (0-1000 mL/min) and its impact on the cell's efficiency and durability. Finally, we investigate the quality orientation (three different positions) of the fuel cell stack, which can significantly affect the cell's lifetime and overall performance. The basis of our analysis is the utilization of experimental results, which have been further validated by comparing them with simulations and manufacturer results. Our results indicate that power fluctuations can cause significant variations in the fuel cell's voltage and current, leading to a reduction in its performance. Moreover, we show that increasing the hydrogen utilization rate beyond a certain threshold can lead to a decrease in the fuel cell's efficiency. Finally, our analysis demonstrates that the orientation of the fuel cell stack can affect its performance and lifetime due to non-uniform distribution of reactants and products. In summary, our study highlights the importance of considering power fluctuations, hydrogen utilization, and quality orientation in designing and optimizing PEM fuel cell systems. The findings of this study can be useful for researchers and engineers working on the development of fuel cell systems for various applications, including transportation, stationary power generation, and portable devices.

Keywords: fuel cell, proton exchange membrane, renewable energy, power fluctuation, experimental

Procedia PDF Downloads 112