Iran’s removing subsidy from energy carrier in four years ago leads to spike electricity price dramatically. This abrupt change increases the interest on distributed generation (DG) because of its several benefits su...Iran’s removing subsidy from energy carrier in four years ago leads to spike electricity price dramatically. This abrupt change increases the interest on distributed generation (DG) because of its several benefits such as lower electricity generation price. In Iran among all type of DGs, because of wide natural gas network infrastructure and several incentives that government legislated to support combined cooling, heat and power (CCHP) investors, this type of technology is more prevalent in comparison with other technologies. Between existing CCHP technologies, certain economic choices are to be taken into account. For different buildings with different load curves, suitable size and operation of CCHP should be calculated to make the project more feasible. If CCHP does not well suited for a position, then the whole energy efficiency would be plunged significantly. In this paper, a model to find the optimal size and operation of CCHP and auxiliary boiler for any users is proposed by considering an integrated view of electricity and natural gas network using GAMS software. Then this method is applying for a hospital in Tehran as a real case study. Finally, by applying COMFAR III software, useful financial parameters and sensitivity analysis are calculated.展开更多
This paper proposed an initiative optimization operation strategy and multi-objective energy management method for combined cooling heating and power(CCHP) with storage systems.Initially,the initiative optimization op...This paper proposed an initiative optimization operation strategy and multi-objective energy management method for combined cooling heating and power(CCHP) with storage systems.Initially,the initiative optimization operation strategy of CCHP system in the cooling season,the heating season and the transition season was formulated.The energy management of CCHP system was optimized by the multi-objective optimization model with maximum daily energy efficiency,minimum daily carbon emissions and minimum daily operation cost based on the proposed initiative optimization operation strategy.Furthermore,the pareto optimal solution set was solved by using the niche particle swarm multi-objective optimization algorithm.Ultimately,the most satisfactory energy management scheme was obtained by using the technique for order preference by similarity to ideal solution(TOPSIS) method.A case study of CCHP system used in a hospital in the north of China validated the effectiveness of this method.The results showed that the satisfactory energy management scheme of CCHP system was obtained based on this initiative optimization operation strategy and multi-objective energy management method.The CCHP system has achieved better energy efficiency,environmental protection and economic benefits.展开更多
Syngas fuel such as hydrogen and carbon monoxide generated by solar energy is a promising method to use solar energy and overcome its fluctuation effectively.This study proposes a combined cooling,heating,and power sy...Syngas fuel such as hydrogen and carbon monoxide generated by solar energy is a promising method to use solar energy and overcome its fluctuation effectively.This study proposes a combined cooling,heating,and power system using the reversible solid oxide fuel cell assisted by solar energy to produce solar fuel and then supply energy products for users during the period without solar radiation.The system runs a solar-assisted solid oxide electrolysis cell mode and a solid oxide fuel cell mode.The thermodynamic models are constructed,and the energetic and exergetic performances are analyzed.Under the design work conditions,the SOEC mode’s overall system energy and exergy efficiencies are 19.0%and 20.5%,respectively.The electrical,energy and exergy efficiencies in the SOFC mode are 51.4%,71.3%,and 45.2%,respectively.The solid oxide fuel cell accounts for 60.0%of total exergy destruction,caused by the electrochemical reactions’thermodynamic irreversibilities.The increase of operating temperature of solid oxide fuel cell from 800℃to 1050℃rises the exergy and energy efficiencies by 11.3%and 12.3%,respectively.Its pressure from 0.2 to 0.7 MPa improves electrical efficiency by 13.8%while decreasing energy and exergy efficiencies by 5.2%and 6.0%,respectively.展开更多
Although numerous studies have considered the two traditional operation strategies:following the electric load(FEL)and following the thermal load(FTL),for combined cooling,heating,and power(CCHP)systems in different c...Although numerous studies have considered the two traditional operation strategies:following the electric load(FEL)and following the thermal load(FTL),for combined cooling,heating,and power(CCHP)systems in different case studies,there are limited theoretical studies on the quantification methods to assess the feasibility of these two strategies in different load demands scenarios.Therefore,instead of a case study,we have undertaken a theoretical analysis of the suitable application scenarios for FEL and FTL strategies based on the energy-matching performance between systems'provision and users'demands.To compare the calculation models of energy saving rate(ESR)for FEL and FTL strategies in the left and right sub-regions of the energy-supply curve,a comprehensive parameter(^)that combines three inherently influential factors(off-design operation parameter,energy-matching parameter,and install capacity coefficient)is defined to determine the optimal installed capacity and feasibility of FEL or FTL strategies quantitatively.The results indicate that greater value of x contribute to a better energy saving performance,and FEL strategy shows better performance than FTL in most load demands scenarios,and the optimal installed capacity occurs when the load demand points were located in different regions of the energy-supply curve.Finally,taking a hotel in Beijing as an example,the value of the optimal install capacity coefficient is 0.845 and the FEL strategy is also suggested,and compared to the maximum install capacity,the average values of the ESR on a typical summer day,transition season,and winter can be enhanced by 3.9%,8.8%,and 1.89%,respectively.展开更多
The fluctuations of renewable energy and various energy demands are crucial issues for the optimal design and operation of combined cooling,heating and power(CCHP)system.In this paper,a novel CCHP system is simulated ...The fluctuations of renewable energy and various energy demands are crucial issues for the optimal design and operation of combined cooling,heating and power(CCHP)system.In this paper,a novel CCHP system is simulated with advanced adiabatic compressed air energy storage(AA-CAES)technology as a join to connect with wind energy generation and an internal-combustion engine(ICE).The capital cost of utilities,energy cost,environmental protection cost and primary energy savings ratio(P E S R)are used as system performance indicators.To fulfill the cooling,heating and power requirements of a district and consider the thermal-electric coupling of ICE and AA-CAES in CCHP system,three operation strategies are established to schedule the dispatch of AA-CAES and ICE:ICE priority operation strategy,CAES priority operation strategy and simultaneous operation strategy.Each strategy leads the operation load of AA-CAES or ICE to improve the energy supply efficiency of the system.Moreover,to minimize comprehensive costs and maximize the P E S R,a novel optimization algorithm based on intelligent updating multi-objective differential evolution(MODE)is proposed to solve the optimization model.Considering the multi-interface characteristic and active management ability of the ICE and AA-CAES,the economic benefits and energy efficiency of the three operation strategies are compared by the simulation with the same system configuration.On a typical summer day,the simultaneous strategy is the best solution as the total cost is 3643 USD and the P E S R is 66.1%,while on a typical winter day,the ICE priority strategy is the best solution as the total cost is 4529 USD and the P E S R is 64.4%.The proposed methodology provides the CCHP based AA-CAES system with a better optimized operation.展开更多
针对燃气轮机冷热电联产系统在"以热定电"运行方式下可能造成的电能过剩和部分负荷时效率不高等问题,该文提出一种太阳能与压缩空气耦合储能(solar andcompressed air energy storage,S-CAES)的燃气轮机冷热电联产系统。通过...针对燃气轮机冷热电联产系统在"以热定电"运行方式下可能造成的电能过剩和部分负荷时效率不高等问题,该文提出一种太阳能与压缩空气耦合储能(solar andcompressed air energy storage,S-CAES)的燃气轮机冷热电联产系统。通过燃气轮机冷热电联产系统典型变工况模型和储能系统的Aspen Plus分析模型,获得S-CAES燃气轮机冷热电联产系统的变工况特性;讨论了各子系统的变工况特性和耦合系统在不同储能率下的运行性能,比较了储能系统释气流量调节与空气透平入口温度调节两种调节方式对系统性能的影响。将S-CAES燃气轮机冷热电联产系统用于华南地区某宾馆建筑进行案例分析,结果表明:与无储能燃气轮机冷热电联产系统相比,在夏季、过渡季、冬季典型日,该系统每天分别节约能量16.57、15.94、11.87GJ;平均能量利用率分别提高5.68%、7.88%和4.69%。展开更多
在传统的利用内燃机驱动的冷热电三联供(combined cooling,heating and power,CCHP)系统的基础上,文章提出了结合太阳能发电和内燃机联合驱动的新型冷热电联供系统模型,并加入了储能电池以提高可再生能源的利用率并克服太阳能发电的缺点...在传统的利用内燃机驱动的冷热电三联供(combined cooling,heating and power,CCHP)系统的基础上,文章提出了结合太阳能发电和内燃机联合驱动的新型冷热电联供系统模型,并加入了储能电池以提高可再生能源的利用率并克服太阳能发电的缺点;通过分析新型CCHP系统的能量流动过程,针对该新型模型提出了基于该系统的经济性、一次能源消耗量、用户满足度的多目标优化模型,以天然气的使用量、向电网侧的购电量以及切除的负载数为优化变量,使用字典序优化算法对其进行求解。展开更多
The interest in distributed generation has been increasing in recent years, especially due to technical devel- opment on generation systems that meet environmental and energy policy concerns. One of the most impor- ta...The interest in distributed generation has been increasing in recent years, especially due to technical devel- opment on generation systems that meet environmental and energy policy concerns. One of the most impor- tant distributed energy technologies is Combined Cooling, Heat and Power (CCHP) systems. CCHP is a small and self-contained electric, heating and cooling generation plant that can provide power for households, commercial or industrial facilities. It can reduce power loss and enhance service reliability in distribution systems. The proposed method in this paper determines the optimal size and operation of CCHP, auxiliary boiler and also heat storage unit as elements of an energy hub, for users by an integrated view of electricity and natural gas network. Authors apply cost and benefit analysis in the optimization. To confirm the proposed method, the optimum sizes of these elements are determined for a hotel in Tehran as a case study.展开更多
提出了一种耦合液化天然气压力能的新型冷-热-电联供(CCHP,combined cooling,heating and power)系统.以西安某工业园为研究对象,采用单纯形算法,以经济性最优为目标函数对系统的运行参数进行了优化,分析了电上网政策对设备出力和系统...提出了一种耦合液化天然气压力能的新型冷-热-电联供(CCHP,combined cooling,heating and power)系统.以西安某工业园为研究对象,采用单纯形算法,以经济性最优为目标函数对系统的运行参数进行了优化,分析了电上网政策对设备出力和系统性能的影响,并以能效、火用效和单位产能CO;排放量作为评价指标,对该系统进行了综合评价.结果表明,与常规CCHP系统相比,该新型系统的年费用和单位产能CO;排放量可分别减少2.9×10;元和29.82 g/(kW·h),一次能源利用率和火用效率可分别提高4.05%和0.44%.展开更多
冷热电三联供(combined cooling heating and power,CCHP)系统有着较高的一次能源利用率、较小的环境污染以及较高的经济性等优点,可有效减轻目前困扰全球的环境污染问题,是社会经济、环境可持续发展的需要,也被认为是实现双碳目标的手...冷热电三联供(combined cooling heating and power,CCHP)系统有着较高的一次能源利用率、较小的环境污染以及较高的经济性等优点,可有效减轻目前困扰全球的环境污染问题,是社会经济、环境可持续发展的需要,也被认为是实现双碳目标的手段之一。随着我国3060双碳目标的提出和国内碳交易市场的发展,碳排放问题势必会成为影响CCHP系统运行策略的一个重大因素。为解决在双碳背景下的CCHP系统运行策略优化问题,通过Matlab软件建立CCHP系统的数学模型,分别在碳排放价格与碳排放指标这2种不同约束条件下,以运行成本最低为目标,采用非线性规划法,优化CCHP系统的运行策略,并通过对某建筑的CCHP系统的负荷计算,验证了该数学模型在不同碳排放约束条件下都可很好地提供合适的运行策略,同时也为CCHP系统在双碳背景下的应用与发展提供了参考。展开更多
文摘Iran’s removing subsidy from energy carrier in four years ago leads to spike electricity price dramatically. This abrupt change increases the interest on distributed generation (DG) because of its several benefits such as lower electricity generation price. In Iran among all type of DGs, because of wide natural gas network infrastructure and several incentives that government legislated to support combined cooling, heat and power (CCHP) investors, this type of technology is more prevalent in comparison with other technologies. Between existing CCHP technologies, certain economic choices are to be taken into account. For different buildings with different load curves, suitable size and operation of CCHP should be calculated to make the project more feasible. If CCHP does not well suited for a position, then the whole energy efficiency would be plunged significantly. In this paper, a model to find the optimal size and operation of CCHP and auxiliary boiler for any users is proposed by considering an integrated view of electricity and natural gas network using GAMS software. Then this method is applying for a hospital in Tehran as a real case study. Finally, by applying COMFAR III software, useful financial parameters and sensitivity analysis are calculated.
基金supported by Major International(Regional)Joint Research Project of the National Natural Science Foundation of China(61320106011)National High Technology Research and Development Program of China(863 Program)(2014AA052802)National Natural Science Foundation of China(61573224)
文摘This paper proposed an initiative optimization operation strategy and multi-objective energy management method for combined cooling heating and power(CCHP) with storage systems.Initially,the initiative optimization operation strategy of CCHP system in the cooling season,the heating season and the transition season was formulated.The energy management of CCHP system was optimized by the multi-objective optimization model with maximum daily energy efficiency,minimum daily carbon emissions and minimum daily operation cost based on the proposed initiative optimization operation strategy.Furthermore,the pareto optimal solution set was solved by using the niche particle swarm multi-objective optimization algorithm.Ultimately,the most satisfactory energy management scheme was obtained by using the technique for order preference by similarity to ideal solution(TOPSIS) method.A case study of CCHP system used in a hospital in the north of China validated the effectiveness of this method.The results showed that the satisfactory energy management scheme of CCHP system was obtained based on this initiative optimization operation strategy and multi-objective energy management method.The CCHP system has achieved better energy efficiency,environmental protection and economic benefits.
基金This work was partially supported by the Brook Byers Institute for Sustainable Systems, the Hightower Chair, Georgia Research Alliance, and grants (083604, 1441208) from the US National Science Foundation Program for Emerging Frontiers in Research and Innovation (EFRI).
基金supported by the National Natural Science Foundation of China(Grant No.51876064 and 52090064)the Bureau of Shihezi Science&Technology(Grant No.2021ZD02)。
文摘Syngas fuel such as hydrogen and carbon monoxide generated by solar energy is a promising method to use solar energy and overcome its fluctuation effectively.This study proposes a combined cooling,heating,and power system using the reversible solid oxide fuel cell assisted by solar energy to produce solar fuel and then supply energy products for users during the period without solar radiation.The system runs a solar-assisted solid oxide electrolysis cell mode and a solid oxide fuel cell mode.The thermodynamic models are constructed,and the energetic and exergetic performances are analyzed.Under the design work conditions,the SOEC mode’s overall system energy and exergy efficiencies are 19.0%and 20.5%,respectively.The electrical,energy and exergy efficiencies in the SOFC mode are 51.4%,71.3%,and 45.2%,respectively.The solid oxide fuel cell accounts for 60.0%of total exergy destruction,caused by the electrochemical reactions’thermodynamic irreversibilities.The increase of operating temperature of solid oxide fuel cell from 800℃to 1050℃rises the exergy and energy efficiencies by 11.3%and 12.3%,respectively.Its pressure from 0.2 to 0.7 MPa improves electrical efficiency by 13.8%while decreasing energy and exergy efficiencies by 5.2%and 6.0%,respectively.
基金This work was supported by the National K ey Research and Development Program of China(Grant No.2016 Y F B 0901405)the Science Fund for Creative Research Groups(No.51621062)the National Natural Science Foundation of China(Grant No.51806117,51236004).
文摘Although numerous studies have considered the two traditional operation strategies:following the electric load(FEL)and following the thermal load(FTL),for combined cooling,heating,and power(CCHP)systems in different case studies,there are limited theoretical studies on the quantification methods to assess the feasibility of these two strategies in different load demands scenarios.Therefore,instead of a case study,we have undertaken a theoretical analysis of the suitable application scenarios for FEL and FTL strategies based on the energy-matching performance between systems'provision and users'demands.To compare the calculation models of energy saving rate(ESR)for FEL and FTL strategies in the left and right sub-regions of the energy-supply curve,a comprehensive parameter(^)that combines three inherently influential factors(off-design operation parameter,energy-matching parameter,and install capacity coefficient)is defined to determine the optimal installed capacity and feasibility of FEL or FTL strategies quantitatively.The results indicate that greater value of x contribute to a better energy saving performance,and FEL strategy shows better performance than FTL in most load demands scenarios,and the optimal installed capacity occurs when the load demand points were located in different regions of the energy-supply curve.Finally,taking a hotel in Beijing as an example,the value of the optimal install capacity coefficient is 0.845 and the FEL strategy is also suggested,and compared to the maximum install capacity,the average values of the ESR on a typical summer day,transition season,and winter can be enhanced by 3.9%,8.8%,and 1.89%,respectively.
基金The work was supported by the National Fundamental Research Program of China 973 project(2014CB249201).
文摘The fluctuations of renewable energy and various energy demands are crucial issues for the optimal design and operation of combined cooling,heating and power(CCHP)system.In this paper,a novel CCHP system is simulated with advanced adiabatic compressed air energy storage(AA-CAES)technology as a join to connect with wind energy generation and an internal-combustion engine(ICE).The capital cost of utilities,energy cost,environmental protection cost and primary energy savings ratio(P E S R)are used as system performance indicators.To fulfill the cooling,heating and power requirements of a district and consider the thermal-electric coupling of ICE and AA-CAES in CCHP system,three operation strategies are established to schedule the dispatch of AA-CAES and ICE:ICE priority operation strategy,CAES priority operation strategy and simultaneous operation strategy.Each strategy leads the operation load of AA-CAES or ICE to improve the energy supply efficiency of the system.Moreover,to minimize comprehensive costs and maximize the P E S R,a novel optimization algorithm based on intelligent updating multi-objective differential evolution(MODE)is proposed to solve the optimization model.Considering the multi-interface characteristic and active management ability of the ICE and AA-CAES,the economic benefits and energy efficiency of the three operation strategies are compared by the simulation with the same system configuration.On a typical summer day,the simultaneous strategy is the best solution as the total cost is 3643 USD and the P E S R is 66.1%,while on a typical winter day,the ICE priority strategy is the best solution as the total cost is 4529 USD and the P E S R is 64.4%.The proposed methodology provides the CCHP based AA-CAES system with a better optimized operation.
文摘针对燃气轮机冷热电联产系统在"以热定电"运行方式下可能造成的电能过剩和部分负荷时效率不高等问题,该文提出一种太阳能与压缩空气耦合储能(solar andcompressed air energy storage,S-CAES)的燃气轮机冷热电联产系统。通过燃气轮机冷热电联产系统典型变工况模型和储能系统的Aspen Plus分析模型,获得S-CAES燃气轮机冷热电联产系统的变工况特性;讨论了各子系统的变工况特性和耦合系统在不同储能率下的运行性能,比较了储能系统释气流量调节与空气透平入口温度调节两种调节方式对系统性能的影响。将S-CAES燃气轮机冷热电联产系统用于华南地区某宾馆建筑进行案例分析,结果表明:与无储能燃气轮机冷热电联产系统相比,在夏季、过渡季、冬季典型日,该系统每天分别节约能量16.57、15.94、11.87GJ;平均能量利用率分别提高5.68%、7.88%和4.69%。
文摘在传统的利用内燃机驱动的冷热电三联供(combined cooling,heating and power,CCHP)系统的基础上,文章提出了结合太阳能发电和内燃机联合驱动的新型冷热电联供系统模型,并加入了储能电池以提高可再生能源的利用率并克服太阳能发电的缺点;通过分析新型CCHP系统的能量流动过程,针对该新型模型提出了基于该系统的经济性、一次能源消耗量、用户满足度的多目标优化模型,以天然气的使用量、向电网侧的购电量以及切除的负载数为优化变量,使用字典序优化算法对其进行求解。
文摘The interest in distributed generation has been increasing in recent years, especially due to technical devel- opment on generation systems that meet environmental and energy policy concerns. One of the most impor- tant distributed energy technologies is Combined Cooling, Heat and Power (CCHP) systems. CCHP is a small and self-contained electric, heating and cooling generation plant that can provide power for households, commercial or industrial facilities. It can reduce power loss and enhance service reliability in distribution systems. The proposed method in this paper determines the optimal size and operation of CCHP, auxiliary boiler and also heat storage unit as elements of an energy hub, for users by an integrated view of electricity and natural gas network. Authors apply cost and benefit analysis in the optimization. To confirm the proposed method, the optimum sizes of these elements are determined for a hotel in Tehran as a case study.
文摘提出了一种耦合液化天然气压力能的新型冷-热-电联供(CCHP,combined cooling,heating and power)系统.以西安某工业园为研究对象,采用单纯形算法,以经济性最优为目标函数对系统的运行参数进行了优化,分析了电上网政策对设备出力和系统性能的影响,并以能效、火用效和单位产能CO;排放量作为评价指标,对该系统进行了综合评价.结果表明,与常规CCHP系统相比,该新型系统的年费用和单位产能CO;排放量可分别减少2.9×10;元和29.82 g/(kW·h),一次能源利用率和火用效率可分别提高4.05%和0.44%.
文摘冷热电三联供(combined cooling heating and power,CCHP)系统有着较高的一次能源利用率、较小的环境污染以及较高的经济性等优点,可有效减轻目前困扰全球的环境污染问题,是社会经济、环境可持续发展的需要,也被认为是实现双碳目标的手段之一。随着我国3060双碳目标的提出和国内碳交易市场的发展,碳排放问题势必会成为影响CCHP系统运行策略的一个重大因素。为解决在双碳背景下的CCHP系统运行策略优化问题,通过Matlab软件建立CCHP系统的数学模型,分别在碳排放价格与碳排放指标这2种不同约束条件下,以运行成本最低为目标,采用非线性规划法,优化CCHP系统的运行策略,并通过对某建筑的CCHP系统的负荷计算,验证了该数学模型在不同碳排放约束条件下都可很好地提供合适的运行策略,同时也为CCHP系统在双碳背景下的应用与发展提供了参考。