Search results for: low power consumption
8450 Analysis of Co2 Emission from Thailand's Thermal Power Sector by Divisia Decomposition Approach
Authors: Isara Muangthai, Lin Sue Jane
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Electricity is vital to every country’s economy in the world. For Thailand, the electricity generation sector plays an important role in the economic system, and it is the largest source of CO2 emissions. The aim of this paper is to use the decomposition analysis to investigate the key factors contributing to the changes of CO2 emissions from the electricity sector. The decomposition analysis has been widely used to identify and assess the contributors to the changes in emission trends. Our study adopted the Divisia index decomposition to identify the key factors affecting the evolution of CO2 emissions from Thailand’s thermal power sector during 2000-2011. The change of CO2 emissions were decomposed into five factors, including: Emission coefficient, heat rate, fuel intensity, electricity intensity, and economic growth. Results have shown that CO2 emission in Thailand’s thermal power sector increased 29,173 thousand tons during 2000-2011. Economic growth was found to be the primary factor for increasing CO2 emissions, while the electricity intensity played a dominant role in decreasing CO2 emissions. The increasing effect of economic growth was up to 55,924 million tons of CO2 emissions because the growth and development of the economy relied on a large electricity supply. On the other hand, the shifting of fuel structure towards a lower-carbon content resulted in CO2 emission decline. Since the CO2 emissions released from Thailand’s electricity generation are rapidly increasing, the Thailand government will be required to implement a CO2 reduction plan in the future. In order to cope with the impact of CO2 emissions related to the power sector and to achieve sustainable development, this study suggests that Thailand’s government should focus on restructuring the fuel supply in power generation towards low carbon fuels by promoting the use of renewable energy for electricity, improving the efficiency of electricity use by reducing electricity transmission and the distribution of line losses, implementing energy conservation strategies by enhancing the purchase of energy-saving products, substituting the new power plant technology in the old power plants, promoting a shift of economic structure towards less energy-intensive services and orienting Thailand’s power industry towards low carbon electricity generation.Keywords: co2 emission, decomposition analysis, electricity generation, energy consumption
Procedia PDF Downloads 4728449 Comparison of the Performance of Diesel Engine, Run with Diesel and Safflower Oil Methyl Esters, Using a Piston Which Has Five Grooves on Its Crown
Authors: N. Hiranmai, M. L. S. Deva Kumar
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In this project, it is planned to carry out an experimental investigation on 4- stroke Direct Injection Diesel Engine, which is a single-cylinder, four-stroke, water-cooled, and constant speed engine capable of developing a power output of 3.7 kW at 1500 rpm, run with diesel fuel and also with different proportions of Safflower oil methyl esters, with a piston having five number of grooves on its crown to create turbulence. Various performance parameters, such as brake power, specific fuel consumption, and thermal efficiency, are calculated. At all the load conditions, the performance of the engine is obtained better for blend B40 (40% Safflower oil + 60% of Diesel). At different load conditions, Brake thermal Efficiency (ηbth) is comparatively more for all blends than that for Diesel. At different load conditions, ηith is less for blend B40.Keywords: four-stroke engine, diesel, safflower oil, engine performance, emissions.
Procedia PDF Downloads 888448 Reliability Analysis: A Case Study in Designing Power Distribution System of Tehran Oil Refinery
Authors: A. B. Arani, R. Shojaee
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Electrical power distribution system is one of the vital infrastructures of an oil refinery, which requires wide area of study and planning before construction. In this paper, power distribution reliability of Tehran Refinery’s KHDS/GHDS unit has been taken into consideration to investigate the importance of these kinds of studies and evaluate the designed system. In this regard, the authors chose and evaluated different configurations of electrical power distribution along with the existing configuration with the aim of finding the most suited configuration which satisfies the conditions of minimum cost of electrical system construction, minimum cost imposed by loss of load, and maximum power system reliability.Keywords: power distribution system, oil refinery, reliability, investment cost, interruption cost
Procedia PDF Downloads 8678447 Geared Turbofan with Water Alcohol Technology
Authors: Abhinav Purohit, Shruthi S. Pradeep
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In today’s world, aviation industries are using turbofan engines (permutation of turboprop and turbojet) which meet the obligatory requirements to be fuel competent and to produce enough thrust to propel an aircraft. But one can imagine increasing the work output of this particular machine by reducing the input power. In striving to improve technologies, especially to augment the efficiency of the engine with some adaptations, which can be crooked to new concepts by introducing a step change in the turbofan engine development. One hopeful concept is, to de-couple the fan with the help of reduction gear box in a two spool shaft engine from the rest of the machinery to get more work output with maximum efficiency by reducing the load on the turbine shaft. By adapting this configuration we can get an additional degree of freedom to better optimize each component at different speeds. Since the components are running at different speeds we can get hold of preferable efficiency. Introducing water alcohol mixture to this concept would really help to get better results.Keywords: emissions, fuel consumption, more power, turbofan
Procedia PDF Downloads 4308446 Artificial Bee Colony Based Modified Energy Efficient Predictive Routing in MANET
Authors: Akhil Dubey, Rajnesh Singh
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In modern days there occur many rapid modifications in field of ad hoc network. These modifications create many revolutionary changes in the routing. Predictive energy efficient routing is inspired on the bee’s behavior of swarm intelligence. Predictive routing improves the efficiency of routing in the energetic point of view. The main aim of this routing is the minimum energy consumption during communication and maximized intermediate node’s remaining battery power. This routing is based on food searching behavior of bees. There are two types of bees for the exploration phase the scout bees and for the evolution phase forager bees use by this routing. This routing algorithm computes the energy consumption, fitness ratio and goodness of the path. In this paper we review the literature related with predictive routing, presenting modified routing and simulation result of this algorithm comparison with artificial bee colony based routing schemes in MANET and see the results of path fitness and probability of fitness.Keywords: mobile ad hoc network, artificial bee colony, PEEBR, modified predictive routing
Procedia PDF Downloads 4088445 Kinetics Analysis of Lignocellulose Hydrolysis and Glucose Consumption Using Aspergillus niger in Solid State
Authors: Akida Mulyaningtyas, Wahyudi Budi Sediawan
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One decisive stage in bioethanol production from plant biomass is the hydrolysis of lignocellulosic materials into simple sugars such as glucose. The produced glucose is then fermented into ethanol. This stage is popularly done in biological method by using cellulase that is produced by certain fungi. As it is known, glucose is the main source of nutrition for most microorganisms. Therefore, cutting cellulose into glucose is actually an attempt of microorganism to provide nutrition for itself. So far, this phenomenon has received less attention while it is necessary to identify the quantity of sugar consumed by the microorganism. In this study, we examined the phenomenon of sugar consumption by microorganism on lignocellulosic hydrolysis. We used oil palm empty fruit bunch (OPEFB) as the source of lignocellulose and Aspergillus niger as cellulase-producing fungus. In Indonesia, OPEFB is plantation waste that is difficult to decompose in nature and causes environmental problems. First, OPEFB was pretreated with 1% of NaOH at 170 oC to destroy lignin that hindered A.niger from accessing cellulose. The hydrolysis was performed by growing A.niger on pretreated OPEFB in solid state to minimize the possibility of contamination. The produced glucose was measured every 24 hours for 9 days. We analyzed the kinetics of both reactions, i.e., hydrolysis and glucose consumption, simultaneously. The constants for both reactions were assumed to follow the Monod equation. The results showed that the reaction constant of glucose consumption (μC) was higher than of cellulose hydrolysis (μH), i.e., 11.8 g/L and 0.62 g/L for glucose consumption and hydrolysis respectively. However, in general, the reaction rate of hydrolysis is greater than of glucose consumption since the cellulose concentration as substrate in hydrolysis is much higher than glucose as substrate in the consumption reaction.Keywords: Aspergillus niger, bioethanol, hydrolysis, kinetics
Procedia PDF Downloads 1578444 Barriers for Sustainable Consumption of Antifouling Products in the Baltic Sea
Authors: Bianca Koroschetz, Emma Mäenpää
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The purpose of this paper is to study consumer practices and meanings of different antifouling methods in order to identify the main barriers for sustainable consumption of antifouling products in the Baltic Sea. The Baltic Sea is considered to be an important tourism area. More than 3.5 million leisure boaters use the sea for recreational boating. Most leisure boat owners use toxic antifouling paint to keep barnacles from attaching to the hull. Attached barnacles limit maneuverability and add drag which in turn increases fuel costs. Antifouling paint used to combat barnacles causes particular problems, as the use of these products continuously adds to the distribution of biocides in the coastal ecosystem and leads to the death of marine organisms. To keep the Baltic Sea as an attractive tourism area measures need to be undertaken to stop the pollution coming from toxic antifouling paints. The antifouling market contains a wide range of environment-friendly alternative products such as a brush wash for boats, hand scrubbing devices, hull covers and boat lifts. Unfortunately, not a lot of boat owners use these environment-friendly alternatives and instead prefer the use of the traditional toxic copper paints. We ask “Why is the unsustainable consumption of toxic paints still predominant when there is a big range of environment-friendly alternatives available? What are the barriers for sustainable consumption?” Environmental psychology has concentrated on developing models of human behavior, including the main factors that influence pro-environmental behavior. The main focus of these models was directed to the individual’s attitudes, principals, and beliefs. However, social practice theory emphasizes the importance to study practices, as they have a stronger explanatory power than attitude-behavior to explain unsustainable consumer behavior. Thus, the study focuses on describing the material, meaning and competence of antifouling practice in order to understand the social and cultural embeddedness of the practice. Phenomenological interviews were conducted with boat owners using antifouling products such as paints and alternative methods. This data collection was supplemented with participant observations in marinas. Preliminary results indicate that different factors such as costs, traditions, advertising, frequency of use, marinas and application of method impact on the consumption of antifouling products. The findings have shown that marinas have a big influence on the consumption of antifouling goods. Some marinas are very active in supporting the sustainable consumption of antifouling products as for example in Stockholm area several marinas subsidize costs for using environmental friendly alternatives or even forbid toxic paints. Furthermore the study has revealed that environmental friendly methods are very effective and do not have to be more expensive than painting with toxic paints. This study contributes to a broader understanding why the unsustainable consumption of toxic paints is still predominant when a big range of environment-friendly alternatives exist. Answers to this phenomenon will be gained by studying practices instead of attitudes offering a new perspective on environmental issues.Keywords: antifouling paint, Baltic Sea, boat tourism, sustainable consumption
Procedia PDF Downloads 1808443 Development of PSS/E Dynamic Model for Controlling Battery Output to Improve Frequency Stability in Power Systems
Authors: Dae-Hee Son, Soon-Ryul Nam
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The power system frequency falls when disturbance such as rapid increase of system load or loss of a generating unit occurs in power systems. Especially, increase in the number of renewable generating units has a bad influence on the power system because of loss of generating unit depending on the circumstance. Conventional technologies use frequency droop control battery output for the frequency regulation and balance between supply and demand. If power is supplied using the fast output characteristic of the battery, power system stability can be further more improved. To improve the power system stability, we propose battery output control using ROCOF (Rate of Change of Frequency) in this paper. The bigger the power difference between the supply and the demand, the bigger the ROCOF drops. Battery output is controlled proportionally to the magnitude of the ROCOF, allowing for faster response to power imbalances. To simulate the control method of battery output system, we develop the user defined model using PSS/E and confirm that power system stability is improved by comparing with frequency droop control.Keywords: PSS/E user defined model, power deviation, frequency droop control, ROCOF (rate of change of frequency)
Procedia PDF Downloads 3928442 Developing Well-Being Indicators and Measurement Methods as Illustrated by Projects Aimed at Preventing Obesity in Children
Authors: E. Grochowska-Niedworok, K. Brukało, M. Hadasik, M. Kardas
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Consumption of vegetables by school children and adolescents is essential for their normal growth, development and health, but a significant minority of the world's population consumes the right amount of these products. The aim of the study was to evaluate the preferences and frequency of consumption of vegetables by school children and adolescents. It has been assumed that effectively implemented nutrition education programs should have an impact on increasing the frequency of vegetable consumption among the recipients. The study covered 514 students of five schools in the Opole Voivodeship aged 9 years to 22 years. The research tool was an author's questionnaire, which consisted of closed questions on the frequency of vegetable consumption and the use of 10 ways to treat them. Preferences and frequencies are shown in percentages, while correlations were estimated on the basis of Cramer`s V and gamma coefficients. In each of the examined age groups, the relationship between sex and vegetable consumption (the Cramer`s V coefficient value was 0.06 to 0.38) was determined and the various methods of culinary processing were used (V Craméra was 0.08 to 0.34). For both sexes, the relationship between age and frequency of vegetable consumption was shown (gamma values ranged from ~ 0.00 to 0.39) and different cooking methods (gamma values were 0.01 to 0.22). The most important determinant of nutritional choices is the taste and availability of products. The fact that they have a positive effect on their health is only in third position. As has been shown, obesity prevention programs can not only address nutrition education but also teach about new flavors and increase the availability of healthy foods. In addition, the frequency of vegetable consumption can be a good indicator reflecting the healthy behaviors of children and adolescents.Keywords: children and adolescents, frequency, welfare rate, vegetables
Procedia PDF Downloads 1958441 Cloud Effect on Power Generation of Grid-Connected Small PV Systems
Authors: Yehya Abdellatif, Ahmed Alsalaymeh, Iyad Muslih, Ali Alshduifat
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Photovoltaic (PV) power generation systems, mainly small scale, are rapidly being deployed in Jordan. The impact of these systems on the grid has not been studied or analyzed. These systems can cause many technical problems such as reverse power flows and voltage rises in distribution feeders, and real and reactive power transients that affect the operation of the transmission system. To fully understand and address these problems, extensive research, simulation, and case studies are required. To this end, this paper studies the cloud shadow effect on the power generation of a ground mounted PV system installed at the test field of the Renewable Energy Center at the Applied Science University.Keywords: photovoltaic, cloud effect, MPPT, power transients
Procedia PDF Downloads 5958440 Sleep Scheduling Schemes Integrating Relay Node and User Equipment in LTE-A
Authors: Chun-Chuan Yang, Jeng-Yueng Chen, Yi-Ting Mai, Hsieh-Hua Liu
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By introduction of Relay Nodes (RNs), LTE-Advanced can provide enhanced coverage and capacity at cell edges and hot-spot areas. The authors have been researching the issue of power saving in mobile communications technology such as WiMax and LTE for some years. Based on the idea of Load-Based Power Saving (LBPS), three efficient power saving schemes for the user equipment (UE) were proposed in the authors’ previous work. In this paper, three revised schemes of the previous work in order to integrate RN and UE in power saving are proposed. Simulation study shows the proposed schemes can achieve significantly better power saving efficiency than the standard based scheme at the cost of moderately increased delay.Keywords: DRX, LTE-A, power saving, RN
Procedia PDF Downloads 5158439 Optimal Power Distribution and Power Trading Control among Loads in a Smart Grid Operated Industry
Authors: Vivek Upadhayay, Siddharth Deshmukh
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In recent years utilization of renewable energy sources has increased majorly because of the increase in global warming concerns. Organization these days are generally operated by Micro grid or smart grid on a small level. Power optimization and optimal load tripping is possible in a smart grid based industry. In any plant or industry loads can be divided into different categories based on their importance to the plant and power requirement pattern in the working days. Coming up with an idea to divide loads in different such categories and providing different power management algorithm to each category of load can reduce the power cost and can come handy in balancing stability and reliability of power. An objective function is defined which is subjected to a variable that we are supposed to minimize. Constraint equations are formed taking difference between the power usages pattern of present day and same day of previous week. By considering the objectives of minimal load tripping and optimal power distribution the proposed problem formulation is a multi-object optimization problem. Through normalization of each objective function, the multi-objective optimization is transformed to single-objective optimization. As a result we are getting the optimized values of power required to each load for present day by use of the past values of the required power for the same day of last week. It is quite a demand response scheduling of power. These minimized values then will be distributed to each load through an algorithm used to optimize the power distribution at a greater depth. In case of power storage exceeding the power requirement, profit can be made by selling exceeding power to the main grid.Keywords: power flow optimization, power trading enhancement, smart grid, multi-object optimization
Procedia PDF Downloads 5178438 Performance Study of PV Power plants in Algeria
Authors: Razika Ihaddadene, Nabila Ihaddadene
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This paper aims to highlight the importance of the application of the IEC 61724 standard in the study of the performance analysis of photovoltaic power plants on a monthly and annual scale. Likewise, the comparison of two photovoltaic power plants with two different climates was carried out in order to determine the effect of climatic parameters on the analysis of photovoltaic performances. All data from the Ain Skhouna and Adrar photovoltaic power plants for 2018 and the data from the Saida1 field for one month in 2019 were used. The results of the performance analysis according to the indicated standard show that the Saida PV power plant performs better than the Adrar PV power plant, which is due to the effect of increasing the ambient temperature. Increasing ambient temperature increases losses decreases system efficiency and performance ratio. It presents a key element in the proper functioning of PV plants.Keywords: pv power plants, IEC 61724 norm, grid connected pv, algeria
Procedia PDF Downloads 668437 Characterization of Laminar Flow and Power Consumption in Agitated Vessel with Curved Blade Agitator
Authors: Amine Benmoussa, Mohamed Bouanini, Mebrouk Rebhi
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Stirring is one of the unifying processes which form part of the mechanical unit operations in process technology such chemical, biotechnological, pharmaceutical, petrochemical, cosmetic, and food processing. Therefore determining the level of mixing and overall behavior and performance of the mixing tanks are crucial from the product quality and process economics point of views. The most fundamental needs for the analysis of these processes from both a theoretical and industrial perspective are the knowledge of the hydrodynamic behavior and the flow structure in such tanks. Depending on the purpose of the operation carried out in mixer, the best choice for geometry of the tank and agitator type can vary widely. Initially, a local and global study namely the velocity and power number on a typical agitation system agitated by a mobile-type two-blade straight (d/D=0.5) allowed us to test the reliability of the CFD, the result were compared with those of experimental literature, a very good concordance was observed. The stream function, the velocity profile, the velocity fields and power number are analyzed. It was shown that the hydrodynamics is modified by the curvature of the mobile which plays a key role.Keywords: agitated vessels, curved blade agitator, laminar flow, finite volume method
Procedia PDF Downloads 2788436 The Enlightenment of the Ventilation System in Chinese Traditional Residence to Architecture Design
Authors: Wu Xingchun, Chen Xi
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Nowadays, China's building energy consumption constitutes 25% of the total energy consumption, half of which was caused by air conditioning in both summer and winter. The ventilation system in Chinese traditional residence, which is totally passive and environmentally friendly, works effectively to create comfortable indoor environment. The research on the ventilation system in Chinese traditional residence can provide advancements to architecture design and energy savings to the society. Through field investigation, case analysis, strategy proposing and other methods, it comes out that the location and layout, the structure system and the design of atrium are the most important elements for a good ventilation system. Taking every factor into consideration, techniques are deployed extensively such as the organization of draught, the design of the thermal pressure ventilation system and the application of modern materials. With the enlightenment of the ventilation system in Chinese traditional residence, we can take effective measures to achieve low energy consumption and sustainable architecture.Keywords: ventilation system, chinese traditional residence, energy consumption, sustainable architecture
Procedia PDF Downloads 7008435 Review on Application of DVR in Compensation of Voltage Harmonics in Power Systems
Authors: S. Sudhharani
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Energy distribution networks are the main link between the energy industry and consumers and are subject to the most scrutiny and testing of any category. As a result, it is important to monitor energy levels during the distribution phase. Power distribution networks, on the other hand, remain subject to common problems, including voltage breakdown, power outages, harmonics, and capacitor switching, all of which disrupt sinusoidal waveforms and reduce the quality and power of the network. Using power appliances in the form of custom power appliances is one way to deal with energy quality issues. Dynamic Voltage Restorer (DVR), integrated with network and distribution networks, is one of these devices. At the same time, by injecting voltage into the system, it can adjust the voltage amplitude and phase in the network. In the form of injections and three-phase syncing, it is used to compensate for the difficulty of energy quality. This article examines the recent use of DVR for power compensation and provides data on the control of each DVR in distribution networks.Keywords: dynamic voltage restorer (DVR), power quality, distribution networks, control systems(PWM)
Procedia PDF Downloads 1298434 Time Series Modelling for Forecasting Wheat Production and Consumption of South Africa in Time of War
Authors: Yiseyon Hosu, Joseph Akande
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Wheat is one of the most important staple food grains of human for centuries and is largely consumed in South Africa. It has a special place in the South African economy because of its significance in food security, trade, and industry. This paper modelled and forecast the production and consumption of wheat in South Africa in the time covid-19 and the ongoing Russia-Ukraine war by using annual time series data from 1940–2021 based on the ARIMA models. Both the averaging forecast and selected models forecast indicate that there is the possibility of an increase with respect to production. The minimum and maximum growth in production is projected to be between 3million and 10 million tons, respectively. However, the model also forecast a possibility of depression with respect to consumption in South Africa. Although Covid-19 and the war between Ukraine and Russia, two major producers and exporters of global wheat, are having an effect on the volatility of the prices currently, the wheat production in South African is expected to increase and meat the consumption demand and provided an opportunity for increase export with respect to domestic consumption. The forecasting of production and consumption behaviours of major crops play an important role towards food and nutrition security, these findings can assist policymakers and will provide them with insights into the production and pricing policy of wheat in South Africa.Keywords: ARIMA, food security, price volatility, staple food, South Africa
Procedia PDF Downloads 918433 Energy Storage in the Future of Ethiopia Renewable Electricity Grid System
Authors: Dawit Abay Tesfamariam
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Ethiopia’s Climate- Resilient Green Economy strategy focuses mainly on generating and utilization of Renewable Energy (RE). The data collected in 2016 by Ethiopian Electric Power (EEP) indicates that the intermittent RE sources on the grid from solar and wind energy were only 8 % of the total energy produced. On the other hand, the EEP electricity generation plan in 2030 indicates that 36 % of the energy generation share will be covered by solar and wind sources. Thus, a case study was initiated to model and compute the balance and consumption of electricity in three different scenarios: 2016, 2025, and 2030 using the Energy PLAN Model (EPM). Initially, the model was validated using the 2016 annual power-generated data to conduct the EPM analysis for two predictive scenarios. The EPM simulation analysis using EPM for 2016 showed that there was no significant excess power generated. Hence, the model’s results are in line with the actual 2016 output. Thus, the EPM was applied to analyze the role of energy storage in RE in Ethiopian grid systems. The results of the EPM simulation analysis showed there will be excess production of 402 /7963 MW average and maximum, respectively, in 2025. The excess power was dominant in all months except in the three rainy months of the year (June, July, and August). Consequently, based on the validated outcomes of EPM indicates, there is a good reason to think about other alternatives for the utilization of excess energy and storage of RE. Thus, from the scenarios and model results obtained, it is realistic to infer that; if the excess power is utilized with a storage mechanism that can stabilize the grid system; as a result, the extra RE generated can be exported to support the economy. Therefore, researchers must continue to upgrade the current and upcoming energy storage system to synchronize with RE potentials that can be generated from RE.Keywords: renewable energy, storage, wind, energyplan
Procedia PDF Downloads 758432 A Consumption-Based Hybrid Life Cycle Assessment of Carbon Footprints in California: High Footprints in Small Urban Households
Authors: Jukka Heinonen
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Higher density reduces distances, private car dependency and thus reduces greenhouse gas emissions (GHGs). As a result, increased density has been given a central role among urban development targets. However, it is not just travel behavior that changes along with density. Rather, the consumption patterns, or overall lifestyles, change along with changing urban structure, particularly with changing housing types and consumption opportunities. Furthermore, elevated consumption of services, more frequent flying and less intra-household sharing have been shown to potentially outweigh the gains from reduced driving in more dense urban settlements. In this study, the geography of carbon footprints (CFs) in California is analyzed paying close attention to the household size differences and the resulting economies-of-scale advantages and disadvantages. A hybrid life cycle assessment (LCA) framework is employed together with consumer expenditure data to assess the CFs. According to the study, small urban households have the highest CFs in California. Their transport related emissions are significantly lower than those of the residents of less urbanized areas, but higher emissions from other consumption categories, together with the low degree of sharing of goods, overweigh the gains. Two functional units, per capita and per household, are used to analyze the CFs and to demonstrate the importance of household size. The lifestyle impacts visible through the consumption data are also discussed. The study suggests that there are still significant gaps in our understanding of the premises of low-carbon human settlements.Keywords: carbon footprint, life cycle assessment, lifestyle, household size, consumption, economies-of-scale
Procedia PDF Downloads 3388431 Design of 900 MHz High Gain SiGe Power Amplifier with Linearity Improved Bias Circuit
Authors: Guiheng Zhang, Wei Zhang, Jun Fu, Yudong Wang
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A 900 MHz three-stage SiGe power amplifier (PA) with high power gain is presented in this paper. Volterra Series is applied to analyze nonlinearity sources of SiGe HBT device model clearly. Meanwhile, the influence of operating current to IMD3 is discussed. Then a β-helper current mirror bias circuit is applied to improve linearity, since the β-helper current mirror bias circuit can offer stable base biasing voltage. Meanwhile, it can also work as predistortion circuit when biasing voltages of three bias circuits are fine-tuned, by this way, the power gain and operating current of PA are optimized for best linearity. The three power stages which fabricated by 0.18 μm SiGe technology are bonded to the printed circuit board (PCB) to obtain impedances by Load-Pull system, then matching networks are done for best linearity with discrete passive components on PCB. The final measured three-stage PA exhibits 21.1 dBm of output power at 1 dB compression point (OP1dB) with power added efficiency (PAE) of 20.6% and 33 dB power gain under 3.3 V power supply voltage.Keywords: high gain power amplifier, linearization bias circuit, SiGe HBT model, Volterra series
Procedia PDF Downloads 3288430 Assessing the Environmental Efficiency of China’s Power System: A Spatial Network Data Envelopment Analysis Approach
Authors: Jianli Jiang, Bai-Chen Xie
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The climate issue has aroused global concern. Achieving sustainable development is a good path for countries to mitigate environmental and climatic pressures, although there are many difficulties. The first step towards sustainable development is to evaluate the environmental efficiency of the energy industry with proper methods. The power sector is a major source of CO2, SO2, and NOx emissions. Evaluating the environmental efficiency (EE) of power systems is the premise to alleviate the terrible situation of energy and the environment. Data Envelopment Analysis (DEA) has been widely used in efficiency studies. However, measuring the efficiency of a system (be it a nation, region, sector, or business) is a challenging task. The classic DEA takes the decision-making units (DMUs) as independent, which neglects the interaction between DMUs. While ignoring these inter-regional links may result in a systematic bias in the efficiency analysis; for instance, the renewable power generated in a certain region may benefit the adjacent regions while the SO2 and CO2 emissions act oppositely. This study proposes a spatial network DEA (SNDEA) with a slack measure that can capture the spatial spillover effects of inputs/outputs among DMUs to measure efficiency. This approach is used to study the EE of China's power system, which consists of generation, transmission, and distribution departments, using a panel dataset from 2014 to 2020. In the empirical example, the energy and patent inputs, the undesirable CO2 output, and the renewable energy (RE) power variables are tested for a significant spatial spillover effect. Compared with the classic network DEA, the SNDEA result shows an obvious difference tested by the global Moran' I index. From a dynamic perspective, the EE of the power system experiences a visible surge from 2015, then a sharp downtrend from 2019, which keeps the same trend with the power transmission department. This phenomenon benefits from the market-oriented reform in the Chinese power grid enacted in 2015. The rapid decline in the environmental efficiency of the transmission department in 2020 was mainly due to the Covid-19 epidemic, which hinders economic development seriously. While the EE of the power generation department witnesses a declining trend overall, this is reasonable, taking the RE power into consideration. The installed capacity of RE power in 2020 is 4.40 times that in 2014, while the power generation is 3.97 times; in other words, the power generation per installed capacity shrank. In addition, the consumption cost of renewable power increases rapidly with the increase of RE power generation. These two aspects make the EE of the power generation department show a declining trend. Incorporation of the interactions among inputs/outputs into the DEA model, this paper proposes an efficiency evaluation method on the basis of the DEA framework, which sheds some light on efficiency evaluation in regional studies. Furthermore, the SNDEA model and the spatial DEA concept can be extended to other fields, such as industry, country, and so on.Keywords: spatial network DEA, environmental efficiency, sustainable development, power system
Procedia PDF Downloads 938429 The Influence of Chinese Philosophic-Religious Traditions on Chinese Consumption Behaviour: Findings from the Taoist Case Study
Authors: Haiping Zhu
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The purpose of this work-in-progress paper is to explore how the Chinese philosophic-religious tradition of Taoism impacts on the consumption behaviour of contemporary Chinese consumers. Although much cultural research has been conducted on Chinese consumption behaviours, most studies have approached the subject from Western perspectives. Examination of the limited literature indicates a gap in the knowledge of the relationship of traditional Chinese Taoism philosophy and Chinese consumption behaviour. To bridge this gap, this study examines Chinese consumption behaviour at a Taoist-related Chinese religious festival - the DuanWu festival - in order to seek some understanding of how the Taoism philosophic-religious tradition influences Chinese consumption behaviour from the point of view of the individuals involved. It focuses attention on their expression of Taoism cultural values, purchasing experience and subsequent consumption behaviours. This study undertook multiple methods for Taoist case study data collection: accompanied shopping with Taoists before DuanWu Festival; participant observations during DuanWu Festival; and in-depth interviews in order to explore Taoists consumption behaviours at the end of the Festival. Specifically, the finding from the Taoist case study corroborates and details the influence of the Taoism doctrine: man–nature orientation, Fenshui, ecological effect, and ecological knowledge, on their attitudes toward green purchasing behaviour. Findings from this Taoist case study - one of a series of three Chinese philosophic religious tradition case studies - contribute to the deeper understanding of contemporary Chinese consumers from a non-Western viewpoint and offer initial insights for global marketers to differentiate consumer needs and develop effective marketing strategies.Keywords: consumer behaviour, culture values, green purchase behaviour, Taoism
Procedia PDF Downloads 2468428 Performance Analysis of Carbon Nanotube for VLSI Interconnects and Their Comparison with Copper Interconnects
Authors: Gagnesh Kumar, Prashant Gupta
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This paper investigates the performance of the bundle of single wall carbon nanotubes (SWCNT) for low-power and high-speed interconnects for future VLSI applications. The power dissipation, delay and power delay product (PDP) of SWCNT bundle interconnects are examined and compared with that of the Cu interconnects at 22 nm technology node for both intermediate and global interconnects. The results show that SWCNT bundle consume less power and also faster than Cu for intermediate and global interconnects. It is concluded that the metallic SWCNT has been regarded as a viable candidate for intermediate and global interconnects in future technologies.Keywords: carbon nanotube, SWCNT, low power, delay, power delay product, global and intermediate interconnects
Procedia PDF Downloads 3128427 Supervisory Board in the Governance of Cooperatives: Disclosing Power Elements in the Selection of Directors
Authors: Kari Huhtala, Iiro Jussila
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The supervisory board is assumed to use power in the governance of a firm, but the actual use of power has been scantly investigated. The research question of the paper is “How does the supervisory board use power in the selection of the board of directors”. The data stem from 11 large Finnish agricultural cooperatives. The research approach was qualitative including semi-structured interviews of the board of directors and supervisory board chairpersons. The results were analyzed and interpreted against theories of social power. As a result, the use of power is approached from two perspectives: (1) formal position-based authority and (2) informal power. Central elements of power were the mandate of the supervisory board, the role of the supervisory board, the supervisory board chair, the nomination committee, collaboration between the supervisory board and the board of directors, the role of regions and the role of the board of directors. The study contributes to the academic discussion on corporate governance in cooperatives and on the supervisory board in the context of the two-tier model. Additional research of the model in other countries and of other types of cooperatives would further academic understanding of supervisory boards.Keywords: board, co-operative, supervisory board, selection, director
Procedia PDF Downloads 1628426 The Mechanism of Design and Analysis Modeling of Performance of Variable Speed Wind Turbine and Dynamical Control of Wind Turbine Power
Authors: Mohammadreza Heydariazad
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Productivity growth of wind energy as a clean source needed to achieve improved strategy in production and transmission and management of wind resources in order to increase quality of power and reduce costs. New technologies based on power converters that cause changing turbine speed to suit the wind speed blowing turbine improve extraction efficiency power from wind. This article introduces variable speed wind turbines and optimization of power, and presented methods to use superconducting inductor in the composition of power converter and is proposed the dc measurement for the wind farm and especially is considered techniques available to them. In fact, this article reviews mechanisms and function, changes of wind speed turbine according to speed control strategies of various types of wind turbines and examines power possible transmission and ac from producing location to suitable location for a strong connection integrating wind farm generators, without additional cost or equipment. It also covers main objectives of the dynamic control of wind turbines, and the methods of exploitation and the ways of using it that includes the unique process of these components. Effective algorithm is presented for power control in order to extract maximum active power and maintains power factor at the desired value.Keywords: wind energy, generator, superconducting inductor, wind turbine power
Procedia PDF Downloads 3208425 Designing Elevations by Photocatalysis of Precast Concrete Materials, in Reducing Energy Consumption of Buildings: Case Study of Tabriz
Authors: Mahsa Faramarzi Asli, Mina Sarabi
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The important issues that are addressed in most advanced industrial countries in recent decades, discussion of minimizing heat losses through the buildings. And the most influential parameters in the calculation of building energy consumption, is heat exchange, which takes place between the interior and outer space. One of the solutions to reduce heat loss is using materials with low thermal conductivity. The purpose of this article, is the effect of using some frontages with nano-concrete photo catalytic precast materials for reducing energy consumption in buildings. For this purpose, estimating the energy dissipation through the facade built with nano-concrete photo catalytic precast materials on a sample building in Tabriz city by BCS 19 software ( topic 19 simulation) is done and the results demonstrate reduce heat loss through the facade nano- concrete.Keywords: nano materials, optimize energy consumption, themal, stability
Procedia PDF Downloads 5538424 Study on Eco-Feedback of Thermal Comfort and Cost Efficiency for Low Energy Residence
Authors: Y. Jin, N. Zhang, X. Luo, W. Zhang
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China with annual increasing 0.5-0.6 billion squares city residence has brought in enormous energy consumption by HVAC facilities and other appliances. In this regard, governments and researchers are encouraging renewable energy like solar energy, geothermal energy using in houses. However, high cost of equipment and low energy conversion result in a very low acceptable to residents. So what’s the equilibrium point of eco-feedback to reach economic benefit and thermal comfort? That is the main question should be answered. In this paper, the objective is an on-site solar PV and heater house, which has been evaluated as a low energy building. Since HVAC system is considered as main energy consumption equipment, the residence with 24-hour monitoring system set to measure temperature, wind velocity and energy in-out value with no HVAC system for one month of summer and winter. Thermal comfort time period will be analyzed and confirmed; then the air-conditioner will be started within thermal discomfort time for the following one summer and winter month. The same data will be recorded to calculate the average energy consumption monthly for a purpose of whole day thermal comfort. Finally, two analysis work will be done: 1) Original building thermal simulation by computer at design stage with actual measured temperature after construction will be contrastive analyzed; 2) The cost of renewable energy facilities and power consumption converted to cost efficient rate to assess the feasibility of renewable energy input for residence. The results of the experiment showed that a certain deviation exists between actual measured data and simulated one for human thermal comfort, especially in summer period. Moreover, the cost-effectiveness is high for a house in targeting city Guilin now with at least 11 years of cost-covering. The conclusion proves that an eco-feedback of a low energy residence is never only consideration of its energy net value, but also the cost efficiency that is the critical factor to push renewable energy acceptable by the public.Keywords: cost efficiency, eco-feedback, low energy residence, thermal comfort
Procedia PDF Downloads 2488423 Validation of Solar PV Inverter Harmonics Behaviour at Different Power Levels in a Test Network
Authors: Wilfred Fritz
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Grid connected solar PV inverters need to be compliant to standard regulations regarding unwanted harmonic generation. This paper gives an introduction to harmonics, solar PV inverter voltage regulation and balancing through compensation and investigates the behaviour of harmonic generation at different power levels. Practical measurements of harmonics and power levels with a power quality data logger were made, on a test network at a university in Germany. The test setup and test results are discussed. The major finding was that between the morning and afternoon load peak windows when the PV inverters operate under low solar insolation and low power levels, more unwanted harmonics are generated. This has a huge impact on the power quality of the grid as well as capital and maintenance costs. The design of a single-tuned harmonic filter towards harmonic mitigation is presented.Keywords: harmonics, power quality, pulse width modulation, total harmonic distortion
Procedia PDF Downloads 2318422 Control Scheme for Single-Stage Boost Inverter for Grid-Connected Photovoltaic
Authors: Mohammad Reza Ebrahimi, Behnaz Mahdaviani
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Increasing renewable sources such photovoltaic are the reason of environmental pollution. Because photovoltaic generates power in low voltage, first, generated power should increase. Usually, distributed generation injects their power to AC-Grid, hence after voltage increasing an inverter is needed to convert DC power to AC power. This results in utilization two series converter that grows cost, complexity, and low efficiency. In this paper a single stage inverter is utilized to boost and invert in one stage. Control of this scheme is easier, and its initial cost decreases comparing to conventional double stage inverters. A simple control scheme is used to control active power as well as minimum total harmonic distortion (THD) in injected current. Simulations in MATLAB demonstrate better outputs comparing with conventional approaches.Keywords: maximum power point tracking, boost inverter, control strategy, three phase inverter
Procedia PDF Downloads 3578421 Home Legacy Device Output Estimation Using Temperature and Humidity Information by Adaptive Neural Fuzzy Inference System
Authors: Sung Hyun Yoo, In Hwan Choi, Jun Ho Jung, Choon Ki Ahn, Myo Taeg Lim
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Home energy management system (HEMS) has been issued to reduce the power consumption. The HEMS performs electric power control for the indoor electric device. However, HEMS commonly treats the smart devices. In this paper, we suggest the output estimation of home legacy device using the artificial neural fuzzy inference system (ANFIS). This paper discusses the overview and the architecture of the system. In addition, accurate performance of the output estimation using the ANFIS inference system is shown via a numerical example.Keywords: artificial neural fuzzy inference system (ANFIS), home energy management system (HEMS), smart device, legacy device
Procedia PDF Downloads 534