The local gas-flow behavior is almost unknown for low pressure plasma systems, except parallel plate reactors for semiconductor purposes. To overcome this lack of knowledge, this study starts with the influence invest...The local gas-flow behavior is almost unknown for low pressure plasma systems, except parallel plate reactors for semiconductor purposes. To overcome this lack of knowledge, this study starts with the influence investigation of the gas feed-in systems technical layout on the homogeneity of the gas supply for large volume plasma enhanced chemical vapor deposition (PECVD) chambers. Computational fluid dynamics (CFD) simulations are used as a tool to determine velocity and pressure distribution inside the gas feed-in pipe as well as in the PECVD-chamber itself. The parameters varied were: flow rate, pipe length, number of holes, hole diameter and aspect ratio of the pipe section. The calculated pressure values are compared with the experimentally measured ones to validate the simulation results. An excellent conformity of the calculated and measured pressures is observed. With the aim to evaluate the homogeneity of gas distribution through the pipe holes the nonuniformity coefficient (Φ) was created. The results show the influence of each layout parameter in the homogeneity of the gas distribution. Hence in future correct technical layouts of gas feed-in systems can easily be applied. With these results construction guidelines has been formulated.展开更多
In recent years, the rapid growth of renewable energy sources (photovoltaic, biomass, geothermal, wind and hydroelectricity) constitutes a feasible solution for environmental problems created by the present production...In recent years, the rapid growth of renewable energy sources (photovoltaic, biomass, geothermal, wind and hydroelectricity) constitutes a feasible solution for environmental problems created by the present production-consumption energy model. Photovoltaic (PV) is one of the most promising, renewable energy sources with great potential for development. Over the last decade, the diffusion of photovoltaic installations in Italy has recorded a considerable increase, displaying at the same time substantial regional dissimilarities. In this paper, we sustain the hypothesis that the installation of PV plants is first of all driven by the financial incentives granted. Using data for Italian provinces, derived under two different editions of the Energy Account, which represents the current Italian financing mechanism, we apply a statistical cluster detection method (the spatial elliptic scan statistics) to identify differences in the spatial distribution of PV plants, in terms of most concentration, throughout the Italian territory. The focus is on mapping the clusters and checking their spatial stability over time, when different subsidy schemes have been adopted. The evidence shows that in the latest detected clusters there are many Northern Italian provinces, with adverse climate conditions (low global irradiance level, low annual temperatures), which have rapidly taken advantage of incentives for solar energy installations.展开更多
This article examines the development of the four main renewable energy technologies (RET) in Spain in the latest years: biomass, small hydro (SH), solar photovoltaic (solar PV) and wind. It has been studied the varia...This article examines the development of the four main renewable energy technologies (RET) in Spain in the latest years: biomass, small hydro (SH), solar photovoltaic (solar PV) and wind. It has been studied the variation of the work-ing time per MW installed available from the on line data base of Spanish National Commission on Energy (SNCE), in the national context and in each of the Autonomic Communities (AACC). We have also obtained the marginal cost curve of the global RE. The main conclusions of the study are that Spain is effective meeting the RE generation target but not efficient in costs and in short term it is not any RETs that can achieve competitive price comparing to the elec-trical market.展开更多
In this study, strategic electricity market scenarios are considered in a grid of Scandinavia. This multiple-objective decision environment includes the allocation of a number of renewable forest fuel procurement chai...In this study, strategic electricity market scenarios are considered in a grid of Scandinavia. This multiple-objective decision environment includes the allocation of a number of renewable forest fuel procurement chains to a combined heat and power plant in Finland. The decision environment includes also electricity procurement from Sweden and Russia. The environment is further complicated by sequence-dependent operations of the local procurement chains during different periods. Due to the complex nature of the environment, multiple-objective methods cannot be directly used to solve the electricity production problem in a manner that is techno-economically relevant to the forest energy industry. Therefore, local and time-varying parameters were measured in local wood procurement conditions to improve the solution method. Using these measurements the smart decision-support system automatically adjusted the multiple-objective methodology to better describe the combinatorial complexity of the production sector. The properties of this methodology are discussed and three scenarios of how the system works based on local real-world data and optional feed-in tariff of green electricity are presented. The Finnish electricity market is subject to policy decisions regarding green energy production regulations. These decisions should be made on the basis of local techno-economic analysis presented in this study accounting for the effects of forest operations on the electricity production and import.展开更多
To assess the effectiveness of China’s emissions trading scheme(ETS)in facilitating energy structure optimization,we constructed a fuel-switching model utilizing data from 1067 generating units under the Chinese ETS ...To assess the effectiveness of China’s emissions trading scheme(ETS)in facilitating energy structure optimization,we constructed a fuel-switching model utilizing data from 1067 generating units under the Chinese ETS framework.The model simulates the fuel-switching price in China’s thermal power sector,taking into account various allowance allocation strategies.The results show the following:1)Thermal power plants will transition from coal to gas if the current ETS auction rate surpasses 26%.2)Furthermore,in scenarios where the ETS operates independently,a transition will occur if the carbon allowance market is entirely auction-based and the carbon price attains 119.50 USD/tCO_(2).3)In a collaborative scenario involving both the ETS and a gas feed-in tariff subsidy,a carbon price of 9.39 USD/tCO_(2)will effect a transition from coal to gas,provided both the auction ratio and subsidy price are maximized.展开更多
Current status and the progress of PV in China are introduced with detailed data,covering PV manufacturing,market development,cost reduction and technology innovation.Fast growing of PV industry in China is due to ser...Current status and the progress of PV in China are introduced with detailed data,covering PV manufacturing,market development,cost reduction and technology innovation.Fast growing of PV industry in China is due to series of incentive policies provided by the Chinese government,which are provided in this paper as well.To slow down the speed of PV development,the 5.31 new policy is issued on May 31,2018 by the Chinese government as a milestone.The affections of the new policy and future PV market are analyzed.The target of energy transition of China and the role of PV are provided.PV will have more broad space in development when it comes to grid parity in the future.展开更多
Developing renewable energy is now becom- ing a hot topic as it is important in dealing with climate change issue and energy supply issue. With the growing demand of energy, it has become urgent to develop the effecti...Developing renewable energy is now becom- ing a hot topic as it is important in dealing with climate change issue and energy supply issue. With the growing demand of energy, it has become urgent to develop the effective policies and measures that would enable people to maintain the living standards. Among all the measures, price is an essential one. In order to evaluate the costs and prices of the electricity from renewable energy sources （RES-E） and their effects to the market, this paper firstly focus on the extra costs of the RES-E by breaking it into four parts, including investment, construction, connection and operation. Then, the policy choices made in some typical industrialized countries are examined to find answers to the problems RES-E can raise. Finally, the choices made in China are examined in comparison to industrialized countries so as to determine how the current situation could be improved.展开更多
文摘The local gas-flow behavior is almost unknown for low pressure plasma systems, except parallel plate reactors for semiconductor purposes. To overcome this lack of knowledge, this study starts with the influence investigation of the gas feed-in systems technical layout on the homogeneity of the gas supply for large volume plasma enhanced chemical vapor deposition (PECVD) chambers. Computational fluid dynamics (CFD) simulations are used as a tool to determine velocity and pressure distribution inside the gas feed-in pipe as well as in the PECVD-chamber itself. The parameters varied were: flow rate, pipe length, number of holes, hole diameter and aspect ratio of the pipe section. The calculated pressure values are compared with the experimentally measured ones to validate the simulation results. An excellent conformity of the calculated and measured pressures is observed. With the aim to evaluate the homogeneity of gas distribution through the pipe holes the nonuniformity coefficient (Φ) was created. The results show the influence of each layout parameter in the homogeneity of the gas distribution. Hence in future correct technical layouts of gas feed-in systems can easily be applied. With these results construction guidelines has been formulated.
文摘In recent years, the rapid growth of renewable energy sources (photovoltaic, biomass, geothermal, wind and hydroelectricity) constitutes a feasible solution for environmental problems created by the present production-consumption energy model. Photovoltaic (PV) is one of the most promising, renewable energy sources with great potential for development. Over the last decade, the diffusion of photovoltaic installations in Italy has recorded a considerable increase, displaying at the same time substantial regional dissimilarities. In this paper, we sustain the hypothesis that the installation of PV plants is first of all driven by the financial incentives granted. Using data for Italian provinces, derived under two different editions of the Energy Account, which represents the current Italian financing mechanism, we apply a statistical cluster detection method (the spatial elliptic scan statistics) to identify differences in the spatial distribution of PV plants, in terms of most concentration, throughout the Italian territory. The focus is on mapping the clusters and checking their spatial stability over time, when different subsidy schemes have been adopted. The evidence shows that in the latest detected clusters there are many Northern Italian provinces, with adverse climate conditions (low global irradiance level, low annual temperatures), which have rapidly taken advantage of incentives for solar energy installations.
文摘This article examines the development of the four main renewable energy technologies (RET) in Spain in the latest years: biomass, small hydro (SH), solar photovoltaic (solar PV) and wind. It has been studied the variation of the work-ing time per MW installed available from the on line data base of Spanish National Commission on Energy (SNCE), in the national context and in each of the Autonomic Communities (AACC). We have also obtained the marginal cost curve of the global RE. The main conclusions of the study are that Spain is effective meeting the RE generation target but not efficient in costs and in short term it is not any RETs that can achieve competitive price comparing to the elec-trical market.
文摘In this study, strategic electricity market scenarios are considered in a grid of Scandinavia. This multiple-objective decision environment includes the allocation of a number of renewable forest fuel procurement chains to a combined heat and power plant in Finland. The decision environment includes also electricity procurement from Sweden and Russia. The environment is further complicated by sequence-dependent operations of the local procurement chains during different periods. Due to the complex nature of the environment, multiple-objective methods cannot be directly used to solve the electricity production problem in a manner that is techno-economically relevant to the forest energy industry. Therefore, local and time-varying parameters were measured in local wood procurement conditions to improve the solution method. Using these measurements the smart decision-support system automatically adjusted the multiple-objective methodology to better describe the combinatorial complexity of the production sector. The properties of this methodology are discussed and three scenarios of how the system works based on local real-world data and optional feed-in tariff of green electricity are presented. The Finnish electricity market is subject to policy decisions regarding green energy production regulations. These decisions should be made on the basis of local techno-economic analysis presented in this study accounting for the effects of forest operations on the electricity production and import.
基金supported by the National Natural Science Foundation of China(Grant No.72304092)the Natural Science Foundation of Hubei Province(Grant No.2022CFB605)+1 种基金the Department of Education of Hubei Province(Grant No.21Y179)the Youth Research Fund of Hubei University of Economics(Grant No.XJZD202302).
文摘To assess the effectiveness of China’s emissions trading scheme(ETS)in facilitating energy structure optimization,we constructed a fuel-switching model utilizing data from 1067 generating units under the Chinese ETS framework.The model simulates the fuel-switching price in China’s thermal power sector,taking into account various allowance allocation strategies.The results show the following:1)Thermal power plants will transition from coal to gas if the current ETS auction rate surpasses 26%.2)Furthermore,in scenarios where the ETS operates independently,a transition will occur if the carbon allowance market is entirely auction-based and the carbon price attains 119.50 USD/tCO_(2).3)In a collaborative scenario involving both the ETS and a gas feed-in tariff subsidy,a carbon price of 9.39 USD/tCO_(2)will effect a transition from coal to gas,provided both the auction ratio and subsidy price are maximized.
文摘Current status and the progress of PV in China are introduced with detailed data,covering PV manufacturing,market development,cost reduction and technology innovation.Fast growing of PV industry in China is due to series of incentive policies provided by the Chinese government,which are provided in this paper as well.To slow down the speed of PV development,the 5.31 new policy is issued on May 31,2018 by the Chinese government as a milestone.The affections of the new policy and future PV market are analyzed.The target of energy transition of China and the role of PV are provided.PV will have more broad space in development when it comes to grid parity in the future.
文摘Developing renewable energy is now becom- ing a hot topic as it is important in dealing with climate change issue and energy supply issue. With the growing demand of energy, it has become urgent to develop the effective policies and measures that would enable people to maintain the living standards. Among all the measures, price is an essential one. In order to evaluate the costs and prices of the electricity from renewable energy sources （RES-E） and their effects to the market, this paper firstly focus on the extra costs of the RES-E by breaking it into four parts, including investment, construction, connection and operation. Then, the policy choices made in some typical industrialized countries are examined to find answers to the problems RES-E can raise. Finally, the choices made in China are examined in comparison to industrialized countries so as to determine how the current situation could be improved.
