为了抑制风电波动,减少弃风量,考虑到配备储热的太阳能热发电(concentrated solar power,CSP)系统具有可调度性,提出了一种风电—CSP联合发电系统。该系统由风电子系统、CSP子系统及电加热(electric heater,EH)子系统组成。其中,EH子系...为了抑制风电波动,减少弃风量,考虑到配备储热的太阳能热发电(concentrated solar power,CSP)系统具有可调度性,提出了一种风电—CSP联合发电系统。该系统由风电子系统、CSP子系统及电加热(electric heater,EH)子系统组成。其中,EH子系统的主要作用是将弃风电能转化为热能,并将热能送入CSP储热子系统(thermal energy storage,TES),既为弃风利用提供一条有效途径,又为CSP增加一个热源,使系统的可调度性和灵活性进一步提高。针对该联合系统,以最小化系统输出负荷与计划负荷间的偏差和最大化能源利用率为目标,建立了其混合整数规划调度模型。以未加EH子系统的风电–CSP联合发电系统为参照,通过案例对比研究了在晴天及部分阴云天气下系统的特性。结果显示该联合系统可更好地跟踪计划负荷,有效降低风电弃风量,为CSP储热子系统提供更多的热能,使系统具有更高的灵活性和可调度性。展开更多
The thermal pyrolysis of natural gas as a clean hydrogen production route is examined. The concept of a double-walled reactor tube is proposed and implemented. Preliminary experiments using an external plasma heating ...The thermal pyrolysis of natural gas as a clean hydrogen production route is examined. The concept of a double-walled reactor tube is proposed and implemented. Preliminary experiments using an external plasma heating source are carried out to validate this concept. The results point out the efficient CH4 dissociation above 1850 K (CH4 conversion over 90%) and the key influence of the gas residence time. Simulations are performed to predict the conversion rate of CH4 at the reactor outlet, and are consistent with experimental tendencies. A solar reactor prototype featuring four independent double-walled tubes is then developed. The heat in high temperature process required for the endothermic reaction of natural gas pyrolysis is supplied by concentrated solar energy. The tubes are heated uniformly by radiation using the blackbody effect of a cavity-receiver absorbing the concentrated solar irradiation through a quartz window. The gas composition at the reactor outlet, the chemical conversion of CH4, and the yield to H2 are determined with respect to reaction temperature, inlet gas flow-rates, and feed gas composition. The longer the gas residence time, the higher the CH4 conversion and H2 yield, whereas the lower the amount of acetylene. A CH4 conversion of 99% and H2 yield of about 85% are measured at 1880 K with 30% CH4 in the feed gas (6 L/min injected and residence time of 18 ms), A temperature increase from 1870 K to 1970 K does not improve the H2 yield.展开更多
The dehydration process of gypsum rock was studied under concentrated solar energy by using a Fresnel lens with power density of 260 Wcm-2. Temperatures higher than 700。C were attained for 1 min of solar exposure. Th...The dehydration process of gypsum rock was studied under concentrated solar energy by using a Fresnel lens with power density of 260 Wcm-2. Temperatures higher than 700。C were attained for 1 min of solar exposure. The effect of grain size of sample and radiation exposure time on the formation of bassanite and anhydrite was studied by XRD. The complete transformation of dihydrate into hemihydrate and/or anhydrate phases is complete for the finer size sample. Plaster composed of 92.7% of anhydrite and 7.3% of bassanite was obtained for 5 min of solar exposure. Morphological and textural modifications were followed by SEM and interferometric/confocal profilometer.展开更多
The demand for energy in Kenya, especially for electricity, is increasing rapidly due to population growth, decentralization of governance, and technological and industrial development. Hydroelectricity, the core sour...The demand for energy in Kenya, especially for electricity, is increasing rapidly due to population growth, decentralization of governance, and technological and industrial development. Hydroelectricity, the core source of power, has proved unreliable due to the rapid climate change. In response, the country has ventured into other renewable sources to counter the issues posed by the alternative nonrenewable sources such as unreliability, high costs, and environmental degradation as seen with the use of diesel and kerosene. The purpose of this research is to determine the viability of setting up a large-scale concentrated solar power plantation in Kenya that will assist in stabilizing Kenya’s energy demand and supply as well as increase its affordability. The project is divided into three phases. The first phase conducts an overlay analysis to determine the Kenya’s solar energy potential. The results show that the northern region has the highest potential. The second step involves the creation of an exclusion mask which eliminates the unsuitable land forms and Land Use Land Cover. Based on the results, the best ten sites are situated in Turkana and Marsabit counties. The final phase involves the evaluation of the potential capacity of power that could be generated per square kilometer. The study finds out that the potential varies based on the technologies: parabolic trough, linear Fresnel reflector, or dish systems.展开更多
In 2011, an innovative technique for concentrating solar light has been introduced in the market—the Linear Mirror. It is a very simple device, and it works well also in winter and in northern climates. In 2012, it w...In 2011, an innovative technique for concentrating solar light has been introduced in the market—the Linear Mirror. It is a very simple device, and it works well also in winter and in northern climates. In 2012, it was certified with the Solar Keymark. Based on this technology, a further improved device was developed and was presented here—the Linear Mirror of second generation (or Linear Mirror II). This is a multi-purpose machine, which overcomes some of the limitations of the previous device. First measurements with the Linear Mirror II are presented in this paper.展开更多
This work uses a mathematical optimization approach to analyze and compare facilities that either capturecarbon dioxide (CO2) artificially or use naturally captured COs in the form of lignocellulosic biomass towardt...This work uses a mathematical optimization approach to analyze and compare facilities that either capturecarbon dioxide (CO2) artificially or use naturally captured COs in the form of lignocellulosic biomass towardthe production of the same product, dimethyl ether (DME). In nature, plants capture COs via photosynthesisin order to grow. The design of the first process discussed here is based on a superstructure optimizationapproach in order to select technologies that transform lignocellulosic biomass into DME. Biomass is gas-ified; next, the raw syngas must be purified using reforming, scrubbing, and carbon capture technologiesbefore it can be used to directly produce DME. Alternatively, CO2 can be captured and used to produce DMEvia hydrogenation. Hydrogen (H2) is produced by splitting water using solar energy. Facilities based on bothphotovoltaic (PV) solar or concentrated solar power (CSP) technologies have been designed; their monthlyoperation, which is based on solar availability, is determined using a multi-period approach. The currentlevel of technological development gives biomass an advantage as a carbon capture technology, since bothwater consumption and economic parameters are in its favor. However, due to the area required for growingbiomass and the total amount of water consumed (if plant growing is also accounted for), the decision to use biomass is not a straightforward one.展开更多
A simple and innovative prototype for biomass pyrolysis is presented, together with some experimental results. The setup uses only the thermal solar energy provided by a system of reflecting mirrors (Linear Mirror II)...A simple and innovative prototype for biomass pyrolysis is presented, together with some experimental results. The setup uses only the thermal solar energy provided by a system of reflecting mirrors (Linear Mirror II) to heat a selected agro-waste biomass, such as wheat straw. At the end of the pyrolysis process, solar carbon with a high energy density (around 24 - 28 MJ/kg) is produced from a biomass with an energy density of 16.9 MJ/kg. The perspectives for a future industrial application of this setup are also discussed.展开更多
多能联供综合能源系统有利于推动能源转型、实现多能源协调互补,已成为能源互联网的重要发展方向。针对以可再生能源为主体的冷热电联供问题,引入热电联产型光热(concentrated solar power,CSP)电站作为核心供能单元,并结合电加热器、...多能联供综合能源系统有利于推动能源转型、实现多能源协调互补,已成为能源互联网的重要发展方向。针对以可再生能源为主体的冷热电联供问题,引入热电联产型光热(concentrated solar power,CSP)电站作为核心供能单元,并结合电加热器、吸收式制冷机、地热源热泵等能量转换设备组成综合能源系统(integrated energy system,IES),提出一种冷热电联供型IES运行优化方法。首先构建了IES架构,并建立了光热电站与建筑物热平衡模型。然后,引入居民舒适度惩罚项,建立了考虑运行成本的IES经济优化模型。在此基础上,建立计及多重不确定性的IES模糊机会约束规划模型。最后,通过算例仿真验证所提策略可以满足居民的不同舒适性需求与提高光热电站的供能潜力,降低系统的运行成本。展开更多
文摘为了抑制风电波动,减少弃风量,考虑到配备储热的太阳能热发电(concentrated solar power,CSP)系统具有可调度性,提出了一种风电—CSP联合发电系统。该系统由风电子系统、CSP子系统及电加热(electric heater,EH)子系统组成。其中,EH子系统的主要作用是将弃风电能转化为热能,并将热能送入CSP储热子系统(thermal energy storage,TES),既为弃风利用提供一条有效途径,又为CSP增加一个热源,使系统的可调度性和灵活性进一步提高。针对该联合系统,以最小化系统输出负荷与计划负荷间的偏差和最大化能源利用率为目标,建立了其混合整数规划调度模型。以未加EH子系统的风电–CSP联合发电系统为参照,通过案例对比研究了在晴天及部分阴云天气下系统的特性。结果显示该联合系统可更好地跟踪计划负荷,有效降低风电弃风量,为CSP储热子系统提供更多的热能,使系统具有更高的灵活性和可调度性。
基金European FP6 research project SOLHYCARB (Contract SES-CT-2006-19770)
文摘The thermal pyrolysis of natural gas as a clean hydrogen production route is examined. The concept of a double-walled reactor tube is proposed and implemented. Preliminary experiments using an external plasma heating source are carried out to validate this concept. The results point out the efficient CH4 dissociation above 1850 K (CH4 conversion over 90%) and the key influence of the gas residence time. Simulations are performed to predict the conversion rate of CH4 at the reactor outlet, and are consistent with experimental tendencies. A solar reactor prototype featuring four independent double-walled tubes is then developed. The heat in high temperature process required for the endothermic reaction of natural gas pyrolysis is supplied by concentrated solar energy. The tubes are heated uniformly by radiation using the blackbody effect of a cavity-receiver absorbing the concentrated solar irradiation through a quartz window. The gas composition at the reactor outlet, the chemical conversion of CH4, and the yield to H2 are determined with respect to reaction temperature, inlet gas flow-rates, and feed gas composition. The longer the gas residence time, the higher the CH4 conversion and H2 yield, whereas the lower the amount of acetylene. A CH4 conversion of 99% and H2 yield of about 85% are measured at 1880 K with 30% CH4 in the feed gas (6 L/min injected and residence time of 18 ms), A temperature increase from 1870 K to 1970 K does not improve the H2 yield.
文摘The dehydration process of gypsum rock was studied under concentrated solar energy by using a Fresnel lens with power density of 260 Wcm-2. Temperatures higher than 700。C were attained for 1 min of solar exposure. The effect of grain size of sample and radiation exposure time on the formation of bassanite and anhydrite was studied by XRD. The complete transformation of dihydrate into hemihydrate and/or anhydrate phases is complete for the finer size sample. Plaster composed of 92.7% of anhydrite and 7.3% of bassanite was obtained for 5 min of solar exposure. Morphological and textural modifications were followed by SEM and interferometric/confocal profilometer.
文摘The demand for energy in Kenya, especially for electricity, is increasing rapidly due to population growth, decentralization of governance, and technological and industrial development. Hydroelectricity, the core source of power, has proved unreliable due to the rapid climate change. In response, the country has ventured into other renewable sources to counter the issues posed by the alternative nonrenewable sources such as unreliability, high costs, and environmental degradation as seen with the use of diesel and kerosene. The purpose of this research is to determine the viability of setting up a large-scale concentrated solar power plantation in Kenya that will assist in stabilizing Kenya’s energy demand and supply as well as increase its affordability. The project is divided into three phases. The first phase conducts an overlay analysis to determine the Kenya’s solar energy potential. The results show that the northern region has the highest potential. The second step involves the creation of an exclusion mask which eliminates the unsuitable land forms and Land Use Land Cover. Based on the results, the best ten sites are situated in Turkana and Marsabit counties. The final phase involves the evaluation of the potential capacity of power that could be generated per square kilometer. The study finds out that the potential varies based on the technologies: parabolic trough, linear Fresnel reflector, or dish systems.
文摘In 2011, an innovative technique for concentrating solar light has been introduced in the market—the Linear Mirror. It is a very simple device, and it works well also in winter and in northern climates. In 2012, it was certified with the Solar Keymark. Based on this technology, a further improved device was developed and was presented here—the Linear Mirror of second generation (or Linear Mirror II). This is a multi-purpose machine, which overcomes some of the limitations of the previous device. First measurements with the Linear Mirror II are presented in this paper.
文摘This work uses a mathematical optimization approach to analyze and compare facilities that either capturecarbon dioxide (CO2) artificially or use naturally captured COs in the form of lignocellulosic biomass towardthe production of the same product, dimethyl ether (DME). In nature, plants capture COs via photosynthesisin order to grow. The design of the first process discussed here is based on a superstructure optimizationapproach in order to select technologies that transform lignocellulosic biomass into DME. Biomass is gas-ified; next, the raw syngas must be purified using reforming, scrubbing, and carbon capture technologiesbefore it can be used to directly produce DME. Alternatively, CO2 can be captured and used to produce DMEvia hydrogenation. Hydrogen (H2) is produced by splitting water using solar energy. Facilities based on bothphotovoltaic (PV) solar or concentrated solar power (CSP) technologies have been designed; their monthlyoperation, which is based on solar availability, is determined using a multi-period approach. The currentlevel of technological development gives biomass an advantage as a carbon capture technology, since bothwater consumption and economic parameters are in its favor. However, due to the area required for growingbiomass and the total amount of water consumed (if plant growing is also accounted for), the decision to use biomass is not a straightforward one.
文摘A simple and innovative prototype for biomass pyrolysis is presented, together with some experimental results. The setup uses only the thermal solar energy provided by a system of reflecting mirrors (Linear Mirror II) to heat a selected agro-waste biomass, such as wheat straw. At the end of the pyrolysis process, solar carbon with a high energy density (around 24 - 28 MJ/kg) is produced from a biomass with an energy density of 16.9 MJ/kg. The perspectives for a future industrial application of this setup are also discussed.
文摘多能联供综合能源系统有利于推动能源转型、实现多能源协调互补,已成为能源互联网的重要发展方向。针对以可再生能源为主体的冷热电联供问题,引入热电联产型光热(concentrated solar power,CSP)电站作为核心供能单元,并结合电加热器、吸收式制冷机、地热源热泵等能量转换设备组成综合能源系统(integrated energy system,IES),提出一种冷热电联供型IES运行优化方法。首先构建了IES架构,并建立了光热电站与建筑物热平衡模型。然后,引入居民舒适度惩罚项,建立了考虑运行成本的IES经济优化模型。在此基础上,建立计及多重不确定性的IES模糊机会约束规划模型。最后,通过算例仿真验证所提策略可以满足居民的不同舒适性需求与提高光热电站的供能潜力,降低系统的运行成本。