In this study, a detailed technical-economic analysis on a O2/CO2 recycle combustion power plant (Oxy-combustion plant) retrofitted from the existing coal-fired plant (with a capacity of 2×300 MW) in China was ca...In this study, a detailed technical-economic analysis on a O2/CO2 recycle combustion power plant (Oxy-combustion plant) retrofitted from the existing coal-fired plant (with a capacity of 2×300 MW) in China was carried out by using life cycle assessment (LCA) and life cycle cost (LCC) method. The CO2 emissions, investment cost, cost of electricity and CO2 avoidance cost within the life cycle were calculated respectively. The results showed that the CO2 emission avoidance rate of retrofitted Oxy-combustion plant in the life cycle was about 77.09% without taking account of the CO2 compression; the annual cost increased by 5.9% approximately, the net power decreased by 21.33%, the cost of electricity increased by 34.77%, and the CO2 avoidance cost was about 28.93 USD/t. Considering the compression process of CO2, the avoidance rate of CO2 emission was about 73.35% or so; the annual cost increased by 9.35% approximately, the net power decreased by about 26.70%, the cost of electricity increased by 49.13%, and the CO2 avoidance cost was about 45.46 USD/t. The carbon tax (the CO2 tax) should be more than about 24 USD/t and 34 USD/t under the condition of considering CO2 compression or not, respectively, which is beneficial to promote transformation of existing coal-fired plant for reducing the CO2 emissions.展开更多
美国燃煤发电厂发展的总体目标是提高效率、环境友好和降低成本.电厂效率要达到55%～56%;SO 2、NO x 及固体颗粒的排放降低到现有标准的1/10以下,二氧化碳及温室气体排放降低50%以上;发电成本在现有基础上减低10%～20%.为实现这些目标,...美国燃煤发电厂发展的总体目标是提高效率、环境友好和降低成本.电厂效率要达到55%～56%;SO 2、NO x 及固体颗粒的排放降低到现有标准的1/10以下,二氧化碳及温室气体排放降低50%以上;发电成本在现有基础上减低10%～20%.为实现这些目标,主要是发展先进的低排放锅炉系统(LEBS)、高性能动力系统(HIPPS)、压力流化床燃烧(PFBC)、整体气化联合循环(IGCC)以及先进的环境控制技术.展开更多
Increasing attention is being paid to the oxycombustion technique of coal-fired power plants because CO 2 produced from fossil fuel combustion can be captured and sequestrated by it. However, there are many questions ...Increasing attention is being paid to the oxycombustion technique of coal-fired power plants because CO 2 produced from fossil fuel combustion can be captured and sequestrated by it. However, there are many questions about the economic properties of the oxy-combustion technique. In this paper, a detailed techno-economic evaluation study was performed on three typical power plants (2 × 300 MW subcritical, 2 × 600 MW supercritical, 2 × 1000 MW ultra supercritical), as conventional air fired and oxycombustion options in China, by utilizing the authoritative data published in 2010 for the design of coal-fired power plants. Techno-economic evaluation models were set up and costs of electricity generation, CO 2 avoidance costs as well as CO 2 capture costs, were calculated. Moreover, the effects of CO 2 tax and CO 2 sale price on the economic characteristics of oxycombustion power plants were also considered. Finally, a sensitivity analysis for parameters such as coal sample, coal price, air separation unit price, flue gas treatment unit price, CO 2 capture efficiency, as well as the air excess factor was conducted. The results revealed that: (1) because the oxy-combustion technique has advantages in thermal efficiency, desulfurization efficiency and denitration efficiency, oxy-combustion power plants will reach the economic properties of conventional air fired power plants if, (a) the CO 2 emission is taxed and the high purity CO 2 product can be sold, or (b) there are some policy preferences in financing and coal price for oxy-combustion power plants, or (c) the power consumption and cost of air separation units and flue gas treatment units can be reduced; (2) from subcritical plants to supercritical and finally ultra-supercritical plants, the economics are improving, regardless of whether they are conventional air fired power plants or oxy-combustion power plants.展开更多
1-year hourly wind speed data from two Burundian stations, namely Bujumbura and Muyinga, have been processed in this work to bring an efficient help for the planning and installation of wind energy conversion systems ...1-year hourly wind speed data from two Burundian stations, namely Bujumbura and Muyinga, have been processed in this work to bring an efficient help for the planning and installation of wind energy conversion systems (WECS) at those localities. Mean seasonal and diurnal variations of wind direction and wind shear exponent have been derived. Two-parameter Weibull probability density functions (PDFs) fitting the observed monthly and annual wind speed relative frequency distributions have been implemented. As shown through three complementary statistical tests, the fitting technique was very satisfactory. A wind resource analysis at 10 m above ground level (AGL) has led to a mean power density at Bujumbura which is almost thirteen fold higher than at Muyinga. The use of the empirical power law to extrapolate wind characteristics at heights from 150 to 350 m AGL has shown that energy potential of hilltops around Muyinga was only suitable for small, individual scale wind energy applications. At the opposite, wind energy potential of ridge-tops and hilltops around Bujumbura has been found suitable for medium and large scale electricity production. For that locality and at those heights, energy outputs and capacity factors (CF or C<sub>f</sub>) have been computed for ten selected wind turbines (WTs), together with costs of electricity (COE) using the present value of cost (PVC) method. Amongst those WTs, YDF-1500-87 and S95-2.1 MW have emerged as the best options for installation owing to their highest CF and lowest COE. Moreover, an analysis of those two quantities at monthly basis for YDF-1500-87 WT has led to its best performance in the dry season. Compared to the average present COE of household hydroelectricity consumption, results of this study have evidenced economical feasibility and benefit of WECS setting in selected Burundian sites in order to supplement traditional electricity sources.展开更多
文章通过可视化软件包展示配电网的最优潮流的计算和分析结果.在考虑输电阻塞的情况下,采用可视化软件包Power World Simulator展示电力系统中以发电成本最低为目标的最优潮流计算和分析的方法,实例表明该软件包能够直观、形象地展示出...文章通过可视化软件包展示配电网的最优潮流的计算和分析结果.在考虑输电阻塞的情况下,采用可视化软件包Power World Simulator展示电力系统中以发电成本最低为目标的最优潮流计算和分析的方法,实例表明该软件包能够直观、形象地展示出配电网最优潮流计算结果和分析过程.展开更多
This paper outlines the barriers and potential benefits of using standby diesel generators in mitigating the peak demands for commercial and industrial customers. The feasibility of utilizing the standby diesel genera...This paper outlines the barriers and potential benefits of using standby diesel generators in mitigating the peak demands for commercial and industrial customers. The feasibility of utilizing the standby diesel generators to reduce the electricity bills for customers is carried out by using the hybrid optimization model for electric renewable(HOMER)software. The size of the standby diesel generator and its operational duration are determined based on the lowest cost of electricity obtained from the evaluations. The economic assessments demonstrate that there is potential to reduce the electricity bills for commercial and industrial customers under the existing fuel price and tariffs. The commercial customers under the tariff C2 have the highest potential to save their electricity bills with the use of standby diesel generators for peak reduction. This study demonstrates the potential of the standby diesel generators in peak reduction.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 40972102, 50936001, 50721005)the National Basic Research Program of China ("973" Program) (Grant No. 2010CB227003)
文摘In this study, a detailed technical-economic analysis on a O2/CO2 recycle combustion power plant (Oxy-combustion plant) retrofitted from the existing coal-fired plant (with a capacity of 2×300 MW) in China was carried out by using life cycle assessment (LCA) and life cycle cost (LCC) method. The CO2 emissions, investment cost, cost of electricity and CO2 avoidance cost within the life cycle were calculated respectively. The results showed that the CO2 emission avoidance rate of retrofitted Oxy-combustion plant in the life cycle was about 77.09% without taking account of the CO2 compression; the annual cost increased by 5.9% approximately, the net power decreased by 21.33%, the cost of electricity increased by 34.77%, and the CO2 avoidance cost was about 28.93 USD/t. Considering the compression process of CO2, the avoidance rate of CO2 emission was about 73.35% or so; the annual cost increased by 9.35% approximately, the net power decreased by about 26.70%, the cost of electricity increased by 49.13%, and the CO2 avoidance cost was about 45.46 USD/t. The carbon tax (the CO2 tax) should be more than about 24 USD/t and 34 USD/t under the condition of considering CO2 compression or not, respectively, which is beneficial to promote transformation of existing coal-fired plant for reducing the CO2 emissions.
文摘美国燃煤发电厂发展的总体目标是提高效率、环境友好和降低成本.电厂效率要达到55%～56%;SO 2、NO x 及固体颗粒的排放降低到现有标准的1/10以下,二氧化碳及温室气体排放降低50%以上;发电成本在现有基础上减低10%～20%.为实现这些目标,主要是发展先进的低排放锅炉系统(LEBS)、高性能动力系统(HIPPS)、压力流化床燃烧(PFBC)、整体气化联合循环(IGCC)以及先进的环境控制技术.
基金supported by the National Basic Research Program of China (2011CB707300)National Natural Science Foundation of China (50936001 and 50721005)New Century Excellent Talents in University of China (NECT-10-0395)
文摘Increasing attention is being paid to the oxycombustion technique of coal-fired power plants because CO 2 produced from fossil fuel combustion can be captured and sequestrated by it. However, there are many questions about the economic properties of the oxy-combustion technique. In this paper, a detailed techno-economic evaluation study was performed on three typical power plants (2 × 300 MW subcritical, 2 × 600 MW supercritical, 2 × 1000 MW ultra supercritical), as conventional air fired and oxycombustion options in China, by utilizing the authoritative data published in 2010 for the design of coal-fired power plants. Techno-economic evaluation models were set up and costs of electricity generation, CO 2 avoidance costs as well as CO 2 capture costs, were calculated. Moreover, the effects of CO 2 tax and CO 2 sale price on the economic characteristics of oxycombustion power plants were also considered. Finally, a sensitivity analysis for parameters such as coal sample, coal price, air separation unit price, flue gas treatment unit price, CO 2 capture efficiency, as well as the air excess factor was conducted. The results revealed that: (1) because the oxy-combustion technique has advantages in thermal efficiency, desulfurization efficiency and denitration efficiency, oxy-combustion power plants will reach the economic properties of conventional air fired power plants if, (a) the CO 2 emission is taxed and the high purity CO 2 product can be sold, or (b) there are some policy preferences in financing and coal price for oxy-combustion power plants, or (c) the power consumption and cost of air separation units and flue gas treatment units can be reduced; (2) from subcritical plants to supercritical and finally ultra-supercritical plants, the economics are improving, regardless of whether they are conventional air fired power plants or oxy-combustion power plants.
文摘1-year hourly wind speed data from two Burundian stations, namely Bujumbura and Muyinga, have been processed in this work to bring an efficient help for the planning and installation of wind energy conversion systems (WECS) at those localities. Mean seasonal and diurnal variations of wind direction and wind shear exponent have been derived. Two-parameter Weibull probability density functions (PDFs) fitting the observed monthly and annual wind speed relative frequency distributions have been implemented. As shown through three complementary statistical tests, the fitting technique was very satisfactory. A wind resource analysis at 10 m above ground level (AGL) has led to a mean power density at Bujumbura which is almost thirteen fold higher than at Muyinga. The use of the empirical power law to extrapolate wind characteristics at heights from 150 to 350 m AGL has shown that energy potential of hilltops around Muyinga was only suitable for small, individual scale wind energy applications. At the opposite, wind energy potential of ridge-tops and hilltops around Bujumbura has been found suitable for medium and large scale electricity production. For that locality and at those heights, energy outputs and capacity factors (CF or C<sub>f</sub>) have been computed for ten selected wind turbines (WTs), together with costs of electricity (COE) using the present value of cost (PVC) method. Amongst those WTs, YDF-1500-87 and S95-2.1 MW have emerged as the best options for installation owing to their highest CF and lowest COE. Moreover, an analysis of those two quantities at monthly basis for YDF-1500-87 WT has led to its best performance in the dry season. Compared to the average present COE of household hydroelectricity consumption, results of this study have evidenced economical feasibility and benefit of WECS setting in selected Burundian sites in order to supplement traditional electricity sources.
文摘This paper outlines the barriers and potential benefits of using standby diesel generators in mitigating the peak demands for commercial and industrial customers. The feasibility of utilizing the standby diesel generators to reduce the electricity bills for customers is carried out by using the hybrid optimization model for electric renewable(HOMER)software. The size of the standby diesel generator and its operational duration are determined based on the lowest cost of electricity obtained from the evaluations. The economic assessments demonstrate that there is potential to reduce the electricity bills for commercial and industrial customers under the existing fuel price and tariffs. The commercial customers under the tariff C2 have the highest potential to save their electricity bills with the use of standby diesel generators for peak reduction. This study demonstrates the potential of the standby diesel generators in peak reduction.
