Yu-hsing Chen, C. Dincan, P. Kjær, C. Bak, Xiongfei Wang, C. Imbaquingo, Eduard Sarrà, Nicola Isernia, A. Tonellotto
This paper focuses on the modelling of the series resonant converter proposed as a DC/DC converter for DC wind turbines. The closed-loop control design based on the discrete time domain modelling technique for the converter (named SRC#) operated in continuous-conduction mode (CCM) is investigated. To facilitate dynamic analysis and design of control structure, the design process includes derivation of linearized state-space equations, design of closed-loop control structure, and design of gain scheduling controller. The analytical results of system are verified in z-domain by comparison of circuit simulator response (in PLECS™) to changes in pulse frequency and disturbances in input and output voltages and show a good agreement. Furthermore, the test results also give enough supporting arguments to proposed control design.
{"title":"Model-Based Control Design of Series Resonant Converter Based on the Discrete Time Domain Modelling Approach for DC Wind Turbine","authors":"Yu-hsing Chen, C. Dincan, P. Kjær, C. Bak, Xiongfei Wang, C. Imbaquingo, Eduard Sarrà, Nicola Isernia, A. Tonellotto","doi":"10.1155/2018/7898679","DOIUrl":"https://doi.org/10.1155/2018/7898679","url":null,"abstract":"This paper focuses on the modelling of the series resonant converter proposed as a DC/DC converter for DC wind turbines. The closed-loop control design based on the discrete time domain modelling technique for the converter (named SRC#) operated in continuous-conduction mode (CCM) is investigated. To facilitate dynamic analysis and design of control structure, the design process includes derivation of linearized state-space equations, design of closed-loop control structure, and design of gain scheduling controller. The analytical results of system are verified in z-domain by comparison of circuit simulator response (in PLECS™) to changes in pulse frequency and disturbances in input and output voltages and show a good agreement. Furthermore, the test results also give enough supporting arguments to proposed control design.","PeriodicalId":30460,"journal":{"name":"Journal of Renewable Energy","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2018/7898679","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47273595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A study was conducted to evaluate the performance of a 1.5 kW micro off-grid solar power generator in a 2-hectare area of a 23-hectare agricultural farm located in Camotes Island, Cebu, Philippines (10°39.4′ N, 124°20.9′ E). The area requires at least 3000 liters of water every day to irrigate its plantation of passion fruit and dragon fruit; however, there is no water source within the immediate vicinity that can support such requirement. A 1/2 horsepower water pump was installed to provide the required irrigation. A 1.5 kW solar photovoltaic (PV) system consisting of 6 units of 250-watts solar PV panel with corresponding 6 units of 200 ampere-hour deep cycle batteries managed by a 3-kW industrial grade inverter provided the power for the water pump and supplied for the electricity demand of the farm. The actual energy usage of the farm was measured from the built-in monitoring of the charge controller and the installed system was analyzed to determine its efficiency in meeting the actual load demand. The HOMER optimization tool was used to determine the optimal configuration for the micro off-grid system based on the actual load demand. Simulation results showed that the optimum configuration that could supply the actual load is a 2.63 kW all-PV system with 8 kWh batteries. Sensitivity analysis was done to consider (1) possible increase in electrical load when the current plantation expands either in progression or outright to its full-scale size of 23 hectares and (2) variations in fuel cost. This study can be considered a good model in assessing renewable energy needs of farms in the country, which can be operationalized for agricultural purposes.
在菲律宾宿务Camotes岛(10°39.4 ' N, 124°20.9 ' E)的一个23公顷农场的2公顷面积上进行了一项1.5 kW微型离网太阳能发电机的性能评估研究,该农场每天至少需要3000升水来灌溉其百香果和火龙果种植园;然而,在附近没有水源可以满足这样的要求。安装了1/2马力的水泵来提供所需的灌溉。一个1.5千瓦的太阳能光伏(PV)系统由6个250瓦的太阳能光伏板和相应的6个200安培小时的深循环电池组成,由一个3千瓦的工业级逆变器管理,为水泵提供动力,满足农场的电力需求。通过充电控制器的内置监控,测量了电厂的实际能源使用情况,并对安装的系统进行了分析,以确定其满足实际负荷需求的效率。利用HOMER优化工具,根据实际负荷需求确定微离网系统的最优配置。仿真结果表明,能够满足实际负荷的最优配置是2.63 kW的全光伏系统配8 kWh电池。进行敏感性分析是为了考虑(1)当当前种植园逐步扩大或完全扩大到23公顷的全面规模时,电力负荷可能增加;(2)燃料成本的变化。这项研究可以被认为是评估该国农场可再生能源需求的一个很好的模型,可以用于农业目的。
{"title":"Performance Evaluation of a Micro Off-Grid Solar Energy Generator for Islandic Agricultural Farm Operations Using HOMER","authors":"Edward M. Querikiol, E. Taboada","doi":"10.1155/2018/2828173","DOIUrl":"https://doi.org/10.1155/2018/2828173","url":null,"abstract":"A study was conducted to evaluate the performance of a 1.5 kW micro off-grid solar power generator in a 2-hectare area of a 23-hectare agricultural farm located in Camotes Island, Cebu, Philippines (10°39.4′ N, 124°20.9′ E). The area requires at least 3000 liters of water every day to irrigate its plantation of passion fruit and dragon fruit; however, there is no water source within the immediate vicinity that can support such requirement. A 1/2 horsepower water pump was installed to provide the required irrigation. A 1.5 kW solar photovoltaic (PV) system consisting of 6 units of 250-watts solar PV panel with corresponding 6 units of 200 ampere-hour deep cycle batteries managed by a 3-kW industrial grade inverter provided the power for the water pump and supplied for the electricity demand of the farm. The actual energy usage of the farm was measured from the built-in monitoring of the charge controller and the installed system was analyzed to determine its efficiency in meeting the actual load demand. The HOMER optimization tool was used to determine the optimal configuration for the micro off-grid system based on the actual load demand. Simulation results showed that the optimum configuration that could supply the actual load is a 2.63 kW all-PV system with 8 kWh batteries. Sensitivity analysis was done to consider (1) possible increase in electrical load when the current plantation expands either in progression or outright to its full-scale size of 23 hectares and (2) variations in fuel cost. This study can be considered a good model in assessing renewable energy needs of farms in the country, which can be operationalized for agricultural purposes.","PeriodicalId":30460,"journal":{"name":"Journal of Renewable Energy","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2018/2828173","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48901925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. J. Lavorante, A. Sanguinetti, H. Fasoli, R. M. Aiello
The analytical development of an equation that allows representing the general behavior of electrochemical cells and, in particular, proton exchange membrane fuel cells is presented in this work. The statement from which the proposed equation emerged was made by Rysselberghe where electrolytic cells work as power supply and around which an electrical current moves out of equilibrium. The data used to test the equation were taken from discharged slopes of PEM fuel cells constructed in the Institute of Scientific and Technical Research for the Defense with researchers from the Army Engineering Faculty and from literature. The equation Pr=Ir(2-Ir) makes it clear that the relative power (Pr) is a quadratic function of the relative current (Ir) and shows a correlation coefficient close to 0.99 with respect to the experimental results of all data analyzed. It is important to remark that the parameters by which the prototypes were constructed were different: the amount and type of catalysts used, the active area, the material of bipolar plates, the type of electrolyte, the number of unit cells, and the different working conditions. In all cases and in spite of all the differences, which are very significant, the parametric equation proposed fits very well.
{"title":"Equation for General Description of Power Behaviour in Fuel Cells","authors":"M. J. Lavorante, A. Sanguinetti, H. Fasoli, R. M. Aiello","doi":"10.1155/2018/2678050","DOIUrl":"https://doi.org/10.1155/2018/2678050","url":null,"abstract":"The analytical development of an equation that allows representing the general behavior of electrochemical cells and, in particular, proton exchange membrane fuel cells is presented in this work. The statement from which the proposed equation emerged was made by Rysselberghe where electrolytic cells work as power supply and around which an electrical current moves out of equilibrium. The data used to test the equation were taken from discharged slopes of PEM fuel cells constructed in the Institute of Scientific and Technical Research for the Defense with researchers from the Army Engineering Faculty and from literature. The equation Pr=Ir(2-Ir) makes it clear that the relative power (Pr) is a quadratic function of the relative current (Ir) and shows a correlation coefficient close to 0.99 with respect to the experimental results of all data analyzed. It is important to remark that the parameters by which the prototypes were constructed were different: the amount and type of catalysts used, the active area, the material of bipolar plates, the type of electrolyte, the number of unit cells, and the different working conditions. In all cases and in spite of all the differences, which are very significant, the parametric equation proposed fits very well.","PeriodicalId":30460,"journal":{"name":"Journal of Renewable Energy","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2018/2678050","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43274333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abigael Okoko, S. von Dach, Juergen Reinhard, B. Kiteme, S. Owuor
In near future, wood-based biomass energy will remain the main cooking energy for households in East Africa, especially for poor households due to its availability and affordability. Alternative biomass fuels however exist. Economic viability of these alternatives is important due to its potential to influence their adoption and sustained use. This research evaluates the economic efficiency of firewood, charcoal, biogas, jatropha oil, and crop residue briquettes value chains in the rural-urban contexts of Kitui, Kenya, and Moshi, Tanzania, using Life Cycle Costing (LCC) methodology. LCC helps to identify areas along the value chains where costs occur and where improvements are feasible. Jatropha oil manual value chain has the highest cost. Firewood use with improved cook stoves is cost efficient. In Moshi’s rural context, royalty fees increases cost of charcoal. Similarly, biogas in Kitui is less likely to be economically viable. Briquettes however have a competitive advantage over charcoal. The costs are dominated by fuel provision compared to cost of stoves. Therefore, payment schemes that improve adoption of improved stoves perceived as expensive will substantially reduce fuel cost. Enhancing availability and accessibility of technologies such as briquette presses will enhance biomass energy access and provide a source of income for households.
{"title":"Life Cycle Costing of Alternative Value Chains of Biomass Energy for Cooking in Kenya and Tanzania","authors":"Abigael Okoko, S. von Dach, Juergen Reinhard, B. Kiteme, S. Owuor","doi":"10.1155/2018/3939848","DOIUrl":"https://doi.org/10.1155/2018/3939848","url":null,"abstract":"In near future, wood-based biomass energy will remain the main cooking energy for households in East Africa, especially for poor households due to its availability and affordability. Alternative biomass fuels however exist. Economic viability of these alternatives is important due to its potential to influence their adoption and sustained use. This research evaluates the economic efficiency of firewood, charcoal, biogas, jatropha oil, and crop residue briquettes value chains in the rural-urban contexts of Kitui, Kenya, and Moshi, Tanzania, using Life Cycle Costing (LCC) methodology. LCC helps to identify areas along the value chains where costs occur and where improvements are feasible. Jatropha oil manual value chain has the highest cost. Firewood use with improved cook stoves is cost efficient. In Moshi’s rural context, royalty fees increases cost of charcoal. Similarly, biogas in Kitui is less likely to be economically viable. Briquettes however have a competitive advantage over charcoal. The costs are dominated by fuel provision compared to cost of stoves. Therefore, payment schemes that improve adoption of improved stoves perceived as expensive will substantially reduce fuel cost. Enhancing availability and accessibility of technologies such as briquette presses will enhance biomass energy access and provide a source of income for households.","PeriodicalId":30460,"journal":{"name":"Journal of Renewable Energy","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2018/3939848","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47235533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anthony A. Bantu, Gilbert Nuwagaba, S. Kizza, Y. Turinayo
In sub-Saharan Africa, dependence on wood fuel has caused significant depletion of vegetative resources. Whereas there exist hundreds of improved cooking stoves, many have not reached their maximum potential because their designs are predominantly focused on either fuel efficiency or reduced smoke. This research designed and fabricated an improved charcoal stove using high density rocks and heat retaining techniques. The aim was to retain heat and minimise heat losses in cooking devices with a sole purpose of reducing the amount of fuel used during cooking. The stove design herein incorporates the interaction of physical and thermal properties of granite rocks with heat loss theories to give a thermal efficient unit. The stove was estimated to cost US$ 36 which compared favourably with most of the improved charcoal stoves on international market (US$ 3–50 US$). This study revealed that, by introducing the new stove design and insulation, the granite rocks depicted high thermal storage properties with potential for reducing fuel use by over 78% with reference to the open fire stove. The designed granite rock stove therefore paves way for the use of high density rocks in improved cook stoves to achieve high performance energy efficient systems that can sustainably put to use vegetative resources.
{"title":"Design of an Improved Cooking Stove Using High Density Heated Rocks and Heat Retaining Techniques","authors":"Anthony A. Bantu, Gilbert Nuwagaba, S. Kizza, Y. Turinayo","doi":"10.1155/2018/9620103","DOIUrl":"https://doi.org/10.1155/2018/9620103","url":null,"abstract":"In sub-Saharan Africa, dependence on wood fuel has caused significant depletion of vegetative resources. Whereas there exist hundreds of improved cooking stoves, many have not reached their maximum potential because their designs are predominantly focused on either fuel efficiency or reduced smoke. This research designed and fabricated an improved charcoal stove using high density rocks and heat retaining techniques. The aim was to retain heat and minimise heat losses in cooking devices with a sole purpose of reducing the amount of fuel used during cooking. The stove design herein incorporates the interaction of physical and thermal properties of granite rocks with heat loss theories to give a thermal efficient unit. The stove was estimated to cost US$ 36 which compared favourably with most of the improved charcoal stoves on international market (US$ 3–50 US$). This study revealed that, by introducing the new stove design and insulation, the granite rocks depicted high thermal storage properties with potential for reducing fuel use by over 78% with reference to the open fire stove. The designed granite rock stove therefore paves way for the use of high density rocks in improved cook stoves to achieve high performance energy efficient systems that can sustainably put to use vegetative resources.","PeriodicalId":30460,"journal":{"name":"Journal of Renewable Energy","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2018/9620103","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45620608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The mini-grid proliferation has helped to improve the current state of electricity supply in several rural areas in developing countries. This is due to the innovations in renewable energy technologies. The impact of this development is the establishment of mini-grid business. There is a need for mini-grid business owners to identify the most suitable energy source for a particular area. To achieve this, proper analysis of risks that impact mini-grid business operations is required for optimal energy source selection. The current study addresses this problem by proposing a conceptual framework that considered risk factors. The conceptual framework analysed scenarios where expected risk values are specified and not specified by decision-makers. This was achieved using fuzzy axiomatic design (FAD), intuitionistic entropy method, and TOPSIS (Technique for Order Performance by Similarity to Ideal Solution) methods. The TOPSIS and FAD results were combined using WASPAS (weighted aggregated sum product assessment) method. The proposed conceptual framework was applied in sub-Sahara Africa, Lagos, Nigeria. During the application of the proposed framework, five renewable energy sources and thirteen types of risks were considered. Information from four decision-makers was used to demonstrate the applicability of the framework. The results obtained showed that unpredictable electricity demand and construction completion risks were identified as the least and most important risks for the selection of renewable energy sources for mini-grid, respectively. The FAD and TOPSIS methods identified wind and biomass energy as the best-ranked energy source for mini-grid business, respectively. The WASPAS method and the FAD results were the same.
{"title":"Determination of a Suitable Renewable Energy Source for Mini-Grid Business: A Risk-Based Multicriteria Approach","authors":"D. Ighravwe, M. O. Babatunde","doi":"10.1155/2018/2163262","DOIUrl":"https://doi.org/10.1155/2018/2163262","url":null,"abstract":"The mini-grid proliferation has helped to improve the current state of electricity supply in several rural areas in developing countries. This is due to the innovations in renewable energy technologies. The impact of this development is the establishment of mini-grid business. There is a need for mini-grid business owners to identify the most suitable energy source for a particular area. To achieve this, proper analysis of risks that impact mini-grid business operations is required for optimal energy source selection. The current study addresses this problem by proposing a conceptual framework that considered risk factors. The conceptual framework analysed scenarios where expected risk values are specified and not specified by decision-makers. This was achieved using fuzzy axiomatic design (FAD), intuitionistic entropy method, and TOPSIS (Technique for Order Performance by Similarity to Ideal Solution) methods. The TOPSIS and FAD results were combined using WASPAS (weighted aggregated sum product assessment) method. The proposed conceptual framework was applied in sub-Sahara Africa, Lagos, Nigeria. During the application of the proposed framework, five renewable energy sources and thirteen types of risks were considered. Information from four decision-makers was used to demonstrate the applicability of the framework. The results obtained showed that unpredictable electricity demand and construction completion risks were identified as the least and most important risks for the selection of renewable energy sources for mini-grid, respectively. The FAD and TOPSIS methods identified wind and biomass energy as the best-ranked energy source for mini-grid business, respectively. The WASPAS method and the FAD results were the same.","PeriodicalId":30460,"journal":{"name":"Journal of Renewable Energy","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2018/2163262","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42848575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The uncertain analysis of fixed solar compound parabolic concentrator (CPC) collector system is investigated for use in combination with solar PV cells. Within solar CPC PV collector systems, any radiation within the collector acceptance angle enters through the aperture and finds its way to the absorber surface by multiple internal reflections. It is essential that the design of any solar collector aims to maximize PV performance since this will elicit a higher collection of solar radiation. In order to analyze uncertainty of the solar CPC collector system in the optimization problem formulation, three objectives are outlined. Seasonal demands are considered for maximizing two of these objectives, the annual average incident solar energy and the lowest month incident solar energy during winter; the lowest cost of the CPC collector system is approached as a third objective. This study investigates uncertain analysis of a solar CPC PV collector system using fuzzy set theory. The fuzzy analysis methodology is suitable for ambiguous problems to predict variations. Uncertain parameters are treated as random variables or uncertain inputs to predict performance. The fuzzy membership functions are used for modeling uncertain or imprecise design parameters of a solar PV collector system. Triangular membership functions are used to represent the uncertain parameters as fuzzy quantities. A fuzzy set analysis methodology is used for analyzing the three objective constrained optimization problems.
{"title":"Uncertain Analysis of a Stationary Solar Compound Parabolic Concentrator PV Collector System Using Fuzzy Set Theory","authors":"Hoe-Gil Lee, Singiresu S. Rao","doi":"10.1155/2018/2915731","DOIUrl":"https://doi.org/10.1155/2018/2915731","url":null,"abstract":"The uncertain analysis of fixed solar compound parabolic concentrator (CPC) collector system is investigated for use in combination with solar PV cells. Within solar CPC PV collector systems, any radiation within the collector acceptance angle enters through the aperture and finds its way to the absorber surface by multiple internal reflections. It is essential that the design of any solar collector aims to maximize PV performance since this will elicit a higher collection of solar radiation. In order to analyze uncertainty of the solar CPC collector system in the optimization problem formulation, three objectives are outlined. Seasonal demands are considered for maximizing two of these objectives, the annual average incident solar energy and the lowest month incident solar energy during winter; the lowest cost of the CPC collector system is approached as a third objective. This study investigates uncertain analysis of a solar CPC PV collector system using fuzzy set theory. The fuzzy analysis methodology is suitable for ambiguous problems to predict variations. Uncertain parameters are treated as random variables or uncertain inputs to predict performance. The fuzzy membership functions are used for modeling uncertain or imprecise design parameters of a solar PV collector system. Triangular membership functions are used to represent the uncertain parameters as fuzzy quantities. A fuzzy set analysis methodology is used for analyzing the three objective constrained optimization problems.","PeriodicalId":30460,"journal":{"name":"Journal of Renewable Energy","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2018/2915731","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45482192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The installation of onshore wind farms has increased in the past decade all over Sweden, and as a result, more wind projects are facing challenges of, for instance, social opposition and lack of space, which potentially complicate resource assessments. As a response to the current challenges in the Swedish wind industry, this study examines and develops a strategic map of potential areas for the construction of new farms in Sweden. The analyses used to prepare the map are performed using a holistic research strategy that focuses on everything from social to technical challenges. The map is based on an extensive data collection consisting of a comprehensive wind dataset mixed with the outcome of large-scale qualitative studies that include five dominant stakeholder groups in the Swedish wind industry and detailed information on restrictive areas. Consequently, this research presents a resource map, which is intended to inspire all stakeholders in the Swedish wind industry to further develop the successful case of wind power in Sweden. Furthermore, the current research aims to update ongoing debates in the wind energy literature, and finally, it introduces a tool that can be used in all phases of a large-scale energy strategy that involves wind power.
{"title":"Mapping the Wind Energy Potential of Sweden: A Sociotechnical Wind Atlas","authors":"P. Enevoldsen, Finn-Hendrik Permien","doi":"10.1155/2018/1650794","DOIUrl":"https://doi.org/10.1155/2018/1650794","url":null,"abstract":"The installation of onshore wind farms has increased in the past decade all over Sweden, and as a result, more wind projects are facing challenges of, for instance, social opposition and lack of space, which potentially complicate resource assessments. As a response to the current challenges in the Swedish wind industry, this study examines and develops a strategic map of potential areas for the construction of new farms in Sweden. The analyses used to prepare the map are performed using a holistic research strategy that focuses on everything from social to technical challenges. The map is based on an extensive data collection consisting of a comprehensive wind dataset mixed with the outcome of large-scale qualitative studies that include five dominant stakeholder groups in the Swedish wind industry and detailed information on restrictive areas. Consequently, this research presents a resource map, which is intended to inspire all stakeholders in the Swedish wind industry to further develop the successful case of wind power in Sweden. Furthermore, the current research aims to update ongoing debates in the wind energy literature, and finally, it introduces a tool that can be used in all phases of a large-scale energy strategy that involves wind power.","PeriodicalId":30460,"journal":{"name":"Journal of Renewable Energy","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2018/1650794","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44725277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ngoc Bich Duong, Shengquan You, L. Huang, Hsiharng Yang
A self-pumping enzymatic biofuel cell (self-pumping EBC) with a new cathodic catalyst which was modified by coating the mixture of carbon nanotubes/caffeic acid (CNTs/CA) on a carbon cloth (CC) to form a CNTs/CA/CC cathode electrode was fabricated. By using UV spectrophotometer, the absorbance of CA, CNTs, and the CNTs/CA composite was observed. To evaluate how the CNTs/CA/CC cathodic electrode improves the electrochemical performance of the self-pumping EBC, the measurement of the redox reaction current peak by cyclic voltammetry (CV) was implemented. In accordance with CV measurement, the utilization of the modified CNTs/CA/CC cathodic electrode exhibited a higher oxygen reduction current peak at 319.1μA under the saturated oxygen. The anode and cathode flow rates were 0.416μls−1 and 0.844 μls−1 which contribute to obtaining the capillary driven liquid efficiency as 30% for the former and 59% for the latter. Moreover, the self-pumping EBC performance tests showed that the maximum power density (MPD) of the self-pumping EBC with the modified cathodic electrode achieved 0.592 mWcm−2 which improved 10% in the performance compared with the bare CC electrode, 0.534 mWcm−2.
{"title":"Carbon Nanotubes Modified Carbon Cloth Cathode Electrode for Self-Pumping Enzymatic Biofuel Cell","authors":"Ngoc Bich Duong, Shengquan You, L. Huang, Hsiharng Yang","doi":"10.1155/2018/8748731","DOIUrl":"https://doi.org/10.1155/2018/8748731","url":null,"abstract":"A self-pumping enzymatic biofuel cell (self-pumping EBC) with a new cathodic catalyst which was modified by coating the mixture of carbon nanotubes/caffeic acid (CNTs/CA) on a carbon cloth (CC) to form a CNTs/CA/CC cathode electrode was fabricated. By using UV spectrophotometer, the absorbance of CA, CNTs, and the CNTs/CA composite was observed. To evaluate how the CNTs/CA/CC cathodic electrode improves the electrochemical performance of the self-pumping EBC, the measurement of the redox reaction current peak by cyclic voltammetry (CV) was implemented. In accordance with CV measurement, the utilization of the modified CNTs/CA/CC cathodic electrode exhibited a higher oxygen reduction current peak at 319.1μA under the saturated oxygen. The anode and cathode flow rates were 0.416μls−1 and 0.844 μls−1 which contribute to obtaining the capillary driven liquid efficiency as 30% for the former and 59% for the latter. Moreover, the self-pumping EBC performance tests showed that the maximum power density (MPD) of the self-pumping EBC with the modified cathodic electrode achieved 0.592 mWcm−2 which improved 10% in the performance compared with the bare CC electrode, 0.534 mWcm−2.","PeriodicalId":30460,"journal":{"name":"Journal of Renewable Energy","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2018/8748731","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47752426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Houston, the fourth largest metropolis in the US, currently experiences severe air pollution. Major pollutants, such as VOCs, CO, NOx, PM, SOx, CH4, and CO2, are released from the transportation fleets. To decrease fossil fuel use and greenhouse gas emissions from fleet vehicles, more and more biodiesel is used in vehicles in the Houston metropolis. The GREET model was used for simulating the fuel cycle emissions of diesel vehicles using different biodiesel blends in Houston. The fuels examined were diesel-biodiesel blends of B0, B5, B20, B50, B80, and B100. The energy and water use and emissions from vehicles fueled with the blends were investigated. The study shows that the reductions in GHG emissions are significant at the Well-to-Pump stage, and all the emissions, except GHGs and NOx, reduce at the Pump-to-Wheel stage. The overall Well-to-Wheel analysis shows that biodiesel is beneficial for both passenger cars and heavy duty trucks. However, the benefits are more pronounced for passenger cars compared to heavy duty vehicles. When 50% of diesel passenger cars and HDDTs are switched to B20 in the Greater Houston area in 2025, the daily GHG emissions will be reduced by 2.0 and 712.1 CO2-equivalent tonnes, respectively.
{"title":"Impacts of Biodiesel Applied to the Transportation Fleets in the Greater Houston Area","authors":"Hongbo Du, Z. Huque, R. Kommalapati","doi":"10.1155/2018/7350715","DOIUrl":"https://doi.org/10.1155/2018/7350715","url":null,"abstract":"Houston, the fourth largest metropolis in the US, currently experiences severe air pollution. Major pollutants, such as VOCs, CO, NOx, PM, SOx, CH4, and CO2, are released from the transportation fleets. To decrease fossil fuel use and greenhouse gas emissions from fleet vehicles, more and more biodiesel is used in vehicles in the Houston metropolis. The GREET model was used for simulating the fuel cycle emissions of diesel vehicles using different biodiesel blends in Houston. The fuels examined were diesel-biodiesel blends of B0, B5, B20, B50, B80, and B100. The energy and water use and emissions from vehicles fueled with the blends were investigated. The study shows that the reductions in GHG emissions are significant at the Well-to-Pump stage, and all the emissions, except GHGs and NOx, reduce at the Pump-to-Wheel stage. The overall Well-to-Wheel analysis shows that biodiesel is beneficial for both passenger cars and heavy duty trucks. However, the benefits are more pronounced for passenger cars compared to heavy duty vehicles. When 50% of diesel passenger cars and HDDTs are switched to B20 in the Greater Houston area in 2025, the daily GHG emissions will be reduced by 2.0 and 712.1 CO2-equivalent tonnes, respectively.","PeriodicalId":30460,"journal":{"name":"Journal of Renewable Energy","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2018/7350715","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46170029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}