Energy plays an essential role in the development of a region. Currently the major source for ene... more Energy plays an essential role in the development of a region. Currently the major source for energy comes from fossil fuel. One of the major unavoidable catastrophic consequences on the utilization of this form of energy is the production of greenhouse gas carbon emission raising the concern about the global challenge of the climate change. The clean renewable power potentially offers a promising solution in delivering clean energy to contribute in the mitigation of the greenhouse gases emissions. The role of developing nations on this mitigation is very important as the major population worldwide lives there. In Indonesia, one of the developing nations, the access of the energy is still becoming a challenge in several of its provinces. Southeast Sulawesi, one of the developing provinces in Indonesia, is still posing the barriers of electricity access for its communities. It is believed that this province has abundant unexplored natural clean energy resources which can be potential...
River current turbine is one of the decentralized alternative energy technologies which is believ... more River current turbine is one of the decentralized alternative energy technologies which is believed to have less environmental impacts and to offer no complex civil work. This study is the continuous work of previous study on developing a mathematical model for predicting the performance of the river current turbine. In present model, the effect of turbine rotation is included, providing a widening understanding on the behavior of the turbine. To develop the model, the momentum theory which is generally applied for wind turbine is adopted. To apply to the model, it requires inputting parameters of the water velocity, the turbine radius, the wind rotational velocity and the blade rotational velocity to calculate the performance. Verification and parametric study using the model are demonstrated and the limitation of the model is discussed.
The mechanism of the kinetic energy conversion has been utilized in many applications in renewabl... more The mechanism of the kinetic energy conversion has been utilized in many applications in renewable energy technologies. One of the applications is a horizontal axis wind turbine. In deciding the number of the blade to be put into the turbine design, instead of the design costs and the construction constraints, the effect of the number on the performance also is one of the aspects needed to be considered. Many studies attempt to investigate theoretically, computationally and experimentally the effect of blade number on the turbine performance. But, it seems that less comprehensive information is derived from these studies regarding to the factor contributing to the results of the investigation. This study investigates the effect the number of blades on the performance of the horizontal axis wind turbine in a variation of a rotation operation and a wind velocity, and attempts to explore comprehensively the reason behind the results of the investigation. The method utilized is a parame...
Energy plays important role in the development of a region. Electricity is one of the energy form... more Energy plays important role in the development of a region. Electricity is one of the energy forms which have been accepted as one of the driving forces of the economic development of all the nations. Southeast Sulawesi, one of the developing regions in Indonesia, apparently still has a problem of electricity provision of its community. The geography–topography condition seems to be one of the main causes for the problem. This paper attempts to deliver a discussion on the prospect of renewable utilization for electricity generation in Southwest Sulawesi. As the sources for the discussion, journal papers, magazines and the authentic government data are utilized. The discussion sub topic will includes the geography and socio-economic condition, the electricity utilization and the problems and the prospect of renewable energy development. It is concluded that Southeast Sulawesi has abundant potential renewable energy sources which can be utilized to assist in delivering energy for the ...
The power system using the clean decentralized renewable horizontal axis river current turbine ca... more The power system using the clean decentralized renewable horizontal axis river current turbine can be an alternative option in delivering locally and sustainably the energies for the communities inaccessible to the electricity connection. One of the important aspects in the technology design is the selection of the blade number. This aspects can raise several consequences including the performance, the manufacturing cost and the construction constrain. The performance must be on the top of the priority in the technology design as the river velocity is typically low which effortlessly brings the technology uneconomically attractive. This study deals with the investigation of effect of the blade number on the performance of the horizontal axis river turbine for low speed condition. The investigation is conducted by a parametric study with the mathematical model of the Blade Element Momentum. The results indicate that turbines with high blade number deliver a better performance than those with the lower blade number. However, the consequences will be the low rotation for the high bladed turbines thus requiring a high gearing ratio for the mechanical transmission. This study also discusses the reason for the results of the investigation and presents a recommendation for designing of the river turbine for such low speed condition in relation to the decision of the blade number.
International Journal of Energy and Environmental Engineering, 2013
ABSTRACT The power system based on the horizontal axis turbines has been extensively employed to ... more ABSTRACT The power system based on the horizontal axis turbines has been extensively employed to harness the kinetic energy of the moving fluid to generate the clean renewable energy in several domains, such as wind, river, and sea. The characteristic of the rotational speed is one of the prominent aspects in designing the power based on the horizontal axis turbine. This is the characteristic that can determine the quantity of the electricity production in the generator on the power technology system. The number of blades is another important aspect in designing the technology. It is believed that the number of blades not only determines the aerodynamic performance, the construction, and the production cost but also the turbine rotational speed characteristics. This study investigates the effect of the blade number on the rotational speed characteristic of a horizontal axis river current turbine. The methodology of generating the investigation is a parametric study using the blade element momentum theory. The result shows that the turbines with low blade number have high rotational speed characteristics while the turbines with high blade number have low rotational speed characteristics. The very low attack angle which yields into a low lift coefficient is one of the factors responsible for the inability of the turbines with high blade number to operate at high rotation. A further discussion on the results on this investigation relating to the hydrodynamic behavior is explored in this study. It is recommended that when a turbine is decided to have a high blade number, the transmission ratio should be high to obtain a high rotation in the generator.
ABSTRACT We describe a potential use of the Lumen Method for daylighting applications in commerci... more ABSTRACT We describe a potential use of the Lumen Method for daylighting applications in commercial buildings in a tropical climate. Calculations of the overall thermal-transfer value show that daylighting and judicious choice of the composition of the building envelope optimize lighting and minimize air-conditioning loads in buildings.
Energy plays an essential role in the development of a region. Currently the major source for ene... more Energy plays an essential role in the development of a region. Currently the major source for energy comes from fossil fuel. One of the major unavoidable catastrophic consequences on the utilization of this form of energy is the production of greenhouse gas carbon emission raising the concern about the global challenge of the climate change. The clean renewable power potentially offers a promising solution in delivering clean energy to contribute in the mitigation of the greenhouse gases emissions. The role of developing nations on this mitigation is very important as the major population worldwide lives there. In Indonesia, one of the developing nations, the access of the energy is still becoming a challenge in several of its provinces. Southeast Sulawesi, one of the developing provinces in Indonesia, is still posing the barriers of electricity access for its communities. It is believed that this province has abundant unexplored natural clean energy resources which can be potential...
River current turbine is one of the decentralized alternative energy technologies which is believ... more River current turbine is one of the decentralized alternative energy technologies which is believed to have less environmental impacts and to offer no complex civil work. This study is the continuous work of previous study on developing a mathematical model for predicting the performance of the river current turbine. In present model, the effect of turbine rotation is included, providing a widening understanding on the behavior of the turbine. To develop the model, the momentum theory which is generally applied for wind turbine is adopted. To apply to the model, it requires inputting parameters of the water velocity, the turbine radius, the wind rotational velocity and the blade rotational velocity to calculate the performance. Verification and parametric study using the model are demonstrated and the limitation of the model is discussed.
The mechanism of the kinetic energy conversion has been utilized in many applications in renewabl... more The mechanism of the kinetic energy conversion has been utilized in many applications in renewable energy technologies. One of the applications is a horizontal axis wind turbine. In deciding the number of the blade to be put into the turbine design, instead of the design costs and the construction constraints, the effect of the number on the performance also is one of the aspects needed to be considered. Many studies attempt to investigate theoretically, computationally and experimentally the effect of blade number on the turbine performance. But, it seems that less comprehensive information is derived from these studies regarding to the factor contributing to the results of the investigation. This study investigates the effect the number of blades on the performance of the horizontal axis wind turbine in a variation of a rotation operation and a wind velocity, and attempts to explore comprehensively the reason behind the results of the investigation. The method utilized is a parame...
Energy plays important role in the development of a region. Electricity is one of the energy form... more Energy plays important role in the development of a region. Electricity is one of the energy forms which have been accepted as one of the driving forces of the economic development of all the nations. Southeast Sulawesi, one of the developing regions in Indonesia, apparently still has a problem of electricity provision of its community. The geography–topography condition seems to be one of the main causes for the problem. This paper attempts to deliver a discussion on the prospect of renewable utilization for electricity generation in Southwest Sulawesi. As the sources for the discussion, journal papers, magazines and the authentic government data are utilized. The discussion sub topic will includes the geography and socio-economic condition, the electricity utilization and the problems and the prospect of renewable energy development. It is concluded that Southeast Sulawesi has abundant potential renewable energy sources which can be utilized to assist in delivering energy for the ...
The power system using the clean decentralized renewable horizontal axis river current turbine ca... more The power system using the clean decentralized renewable horizontal axis river current turbine can be an alternative option in delivering locally and sustainably the energies for the communities inaccessible to the electricity connection. One of the important aspects in the technology design is the selection of the blade number. This aspects can raise several consequences including the performance, the manufacturing cost and the construction constrain. The performance must be on the top of the priority in the technology design as the river velocity is typically low which effortlessly brings the technology uneconomically attractive. This study deals with the investigation of effect of the blade number on the performance of the horizontal axis river turbine for low speed condition. The investigation is conducted by a parametric study with the mathematical model of the Blade Element Momentum. The results indicate that turbines with high blade number deliver a better performance than those with the lower blade number. However, the consequences will be the low rotation for the high bladed turbines thus requiring a high gearing ratio for the mechanical transmission. This study also discusses the reason for the results of the investigation and presents a recommendation for designing of the river turbine for such low speed condition in relation to the decision of the blade number.
International Journal of Energy and Environmental Engineering, 2013
ABSTRACT The power system based on the horizontal axis turbines has been extensively employed to ... more ABSTRACT The power system based on the horizontal axis turbines has been extensively employed to harness the kinetic energy of the moving fluid to generate the clean renewable energy in several domains, such as wind, river, and sea. The characteristic of the rotational speed is one of the prominent aspects in designing the power based on the horizontal axis turbine. This is the characteristic that can determine the quantity of the electricity production in the generator on the power technology system. The number of blades is another important aspect in designing the technology. It is believed that the number of blades not only determines the aerodynamic performance, the construction, and the production cost but also the turbine rotational speed characteristics. This study investigates the effect of the blade number on the rotational speed characteristic of a horizontal axis river current turbine. The methodology of generating the investigation is a parametric study using the blade element momentum theory. The result shows that the turbines with low blade number have high rotational speed characteristics while the turbines with high blade number have low rotational speed characteristics. The very low attack angle which yields into a low lift coefficient is one of the factors responsible for the inability of the turbines with high blade number to operate at high rotation. A further discussion on the results on this investigation relating to the hydrodynamic behavior is explored in this study. It is recommended that when a turbine is decided to have a high blade number, the transmission ratio should be high to obtain a high rotation in the generator.
ABSTRACT We describe a potential use of the Lumen Method for daylighting applications in commerci... more ABSTRACT We describe a potential use of the Lumen Method for daylighting applications in commercial buildings in a tropical climate. Calculations of the overall thermal-transfer value show that daylighting and judicious choice of the composition of the building envelope optimize lighting and minimize air-conditioning loads in buildings.
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