火-储耦合系统深度调峰综合经济性分析

doi:10.19799/j.cnki.2095-4239.2024.0250

储能科学与技术 ›› 2024, Vol. 13 ›› Issue (10): 3693-3705.doi: 10.19799/j.cnki.2095-4239.2024.0250

火-储耦合系统深度调峰综合经济性分析

张成凤¹^,²(), 朱轶林², 胡东子¹^,², 富征阳³, 徐玉杰²(), 沈国清¹(), 王亮², 陈海生²

^1.华北电力大学能源动力与机械工程学院，北京 102206
^2.中国科学院工程热物理研究所，北京 100190
^3.华北电力大学能源动力与机械工程学院，河北保定 071003

收稿日期:2024-03-22 修回日期:2024-04-12 出版日期:2024-10-28 发布日期:2024-10-30
通讯作者: 徐玉杰,沈国清 E-mail:120212202361@ncepu.edu.cn;xuyujie@iet.cn;shenguoqing@ncepu.edu.cn
作者简介:张成凤（1998—），女，硕士研究生，主要研究方向为火电-储热耦合系统深度调峰，E-mail：120212202361@ncepu.edu.cn；
基金资助:
国家重点研发计划项目(2022YFB2405200);北京市自然科学基金(3244047)

Comprehensive economic analysis of deep peak shaving in thermal power-heat storage coupling systems

Chengfeng ZHANG¹^,²(), Yilin ZHU², Dongzi HU¹^,², Zhengyang FU³, Yujie XU²(), Guoqing SHEN¹(), Liang WANG², Haisheng CHEN²

^1.School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
^2.Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China
^3.School of Energy Power and Mechanical Engineering, North China Electric Power University, Baoding 071003, Hebei, China

Received:2024-03-22 Revised:2024-04-12 Online:2024-10-28 Published:2024-10-30
Contact: Yujie XU, Guoqing SHEN E-mail:120212202361@ncepu.edu.cn;xuyujie@iet.cn;shenguoqing@ncepu.edu.cn

摘要/Abstract

摘要：

火电机组耦合储热技术，可提高机组的热电解耦能力，减少深度调峰对系统安全性和经济性的影响。本工作提出了火电机组与填充床储热的耦合系统，在考虑了机组变工况、填充床储/释热过程动态时间序列基础上，通过EBSILON建立了耦合系统变工况仿真模型；分析深度调峰对耦合系统热力性和碳排放量的影响，通过汽水分离器筒体应力变化分析深调对锅炉寿命损耗的影响，通过转子寿命损耗率曲线分析深调对汽轮机寿命的影响，最终建立耦合系统调度运行经济性模型，开展综合经济性分析。结果表明：火-储耦合系统比自身变工况减小碳排放量7418 t/a(仅配置风电)~9216 t/a(仅配置光伏)；深度调峰对锅炉寿命损耗的影响大于汽轮机，火-储耦合系统可提高系统运行寿命，深度调峰318次/年，相比于机组自身变工况(30%~20%额定负荷)可提高13.3%~15.3%；火-储耦合系统深度调峰收益高于火电机组自身变工况，当填充床释热量用于发电或供热时，耦合系统比自身变工况收益分别增加40万元/年、72万元/年。

关键词: 火电机组, 储热, 深度调峰, 综合经济性, 系统寿命, 碳排放

Abstract:

The integration of thermal power plants with heat storage technology can enhance the decoupling capability of the units, thereby reducing the impact of deep peak shaving on the safety and economic viability of the system. This study proposes a coupled system comprising thermal power plants and packed-bed heat storage. Considering the dynamic time series of unit variable operating conditions and packed-bed heat storage/release processes, a simulation model of the coupling system under variable operating conditions was established using Ebsilon. We analyzed the impact of deep peak shaving on the thermal dynamics and carbon emissions of the coupling system. The effect of deep peak shaving on the boiler's life loss rate was investigated by calculating the stress variation of the steam-water separator cylinder. The impact of deep peak shaving on turbine consumption was also examined by analyzing the rotor life loss rate curve. Consequently, an efficient model for the scheduling operation of the coupling system was established to conduct a comprehensive economic analysis. The results show that when the boiler operating status and system power generation remain constant and the power supply structure comprises a renewable energy and energy storage ratio of 5∶1, the coupling system reduces carbon emissions by 7418 t/a (with only wind power) to 9216 t/a (with only photovoltaics) compared with self-variable conditions. The impact of deep peak shaving on the boiler lifespan loss is greater than that on the turbine; however, the coupling system can improve the system lifespan. With deep peak shaving occurring 318 times/a, it can increase by 13.3%—15.3% compared to the unit's self-variable conditions (30%—20% rated load). The economic benefits of deep peak shaving in the coupling system are greater than those of the thermal power plant's self-variable conditions. When the heat released by the packed bed is used for power generation or heating, the benefits of the coupling system increase by 400000 and 720000 RMB/year, respectively, compared to its self-variable conditions.

Key words: thermal power plant, heat storage, deep peak shaving, comprehensive economic performance, system service life, carbon emissions

中图分类号:

TK 02

张成凤, 朱轶林, 胡东子, 富征阳, 徐玉杰, 沈国清, 王亮, 陈海生. 火-储耦合系统深度调峰综合经济性分析[J]. 储能科学与技术, 2024, 13(10): 3693-3705.

Chengfeng ZHANG, Yilin ZHU, Dongzi HU, Zhengyang FU, Yujie XU, Guoqing SHEN, Liang WANG, Haisheng CHEN. Comprehensive economic analysis of deep peak shaving in thermal power-heat storage coupling systems[J]. Energy Storage Science and Technology, 2024, 13(10): 3693-3705.

图/表 19

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参数	单位	数值
额定功率	kW	350018
主蒸汽流量	kg/h	1079300
主蒸汽压力/温度	MPa/℃	24.2/566
再热蒸汽流量	kg/h	3590.4
再热蒸汽压力/温度	MPa/℃	4.723/566
背压	kPa	10
给水温度	℃	288.1
热耗	kJ/kWh	7943

机组工况	主蒸汽流量			主蒸汽压力
机组工况	设计值/(kg/h)	模拟值/(kg/h)	相对误差	设计值/MPa	模拟值/MPa	相对误差
100% 额定负荷	1050763	1050763	0	24.2	24.251	0.211%
50% 额定负荷	496567	496567	0	16.04	16.074	0.212%
40% 额定负荷	402728	402728	0	13.14	13.168	0.213%
30% 额定负荷	311938	311938	0	10.28	10.302	0.214%

参数	单位	数值
长度	mm	3000
内直径	mm	522
外直径	mm	762

参数	单位	数值
线膨胀系数	1/℃	2.35×10^-5
弹性模量	MPa	2.07×10⁵
泊松比	—	0.29

机组运行工况	机组自身变工况		火-储耦合系统
机组运行工况	20%~100%额定负荷	30%~100%额定负荷	20%~100%额定负荷
发电负荷/MW	70~350	105~350	70~350/357
发电效率/%	39.903	39.943	37.057
煤耗率/(g/kWh)	308.23	307.92	331.91

火-储耦合系统深度调峰综合经济性分析

Comprehensive economic analysis of deep peak shaving in thermal power-heat storage coupling systems

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相关文章 15

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机组运行工况	机组自身变工况			火-储耦合系统
机组运行工况	20%额定负荷	30%额定负荷	100%额定负荷	20%额定负荷	100%额定负荷
供电结构	70 MW火电+175 MW风光	105 MW火电	350 MW火电	70 MW火电+175 MW风光	350 MW火电+释热
碳排放来源	70 MW火电+投油+175 MW风光	105 MW火电	350 MW火电	105 MW火电 +175 MW风光	350 MW火电
碳排放量	63.5~69.15 t	85.41 t	223.1 t	86.6~92.25 t	223.09 t

机组运行工况		最大循环应力幅/MPa	破坏次数	寿命损耗率/%	寿命损耗成本/万元
机组自身变工况	20%额定负荷	210	10×10³	1×10^-2	2.4
机组自身变工况	30%额定负荷	180	14.3×10³	7×10^-3	1.68

火-储耦合系统	20%额定负荷	180	14.3×10³	7×10^-3	1.68

机组运行工况		部件	部件实际寿命/年	系统运行年限/年
机组自身变工况	20%额定负荷	锅炉	13.9	13.9
	20%额定负荷	汽轮机	20.95	13.9
	30%额定负荷	锅炉	16.03	16.03
	30%额定负荷	汽轮机	21.71	16.03

火-储耦合系统	20%额定负荷	锅炉	16.03	16.03

机组运行工况	机组自身变工况			火-储耦合系统
机组运行工况	20% 额定负荷	30% 额定负荷	100% 额定负荷	20% 额定负荷	100%额定负荷 (释热1)	100%额定负荷 (释热2)
燃煤成本/元	16444	23574	69806	23574	69806	69806
调峰成本/元	6800	859	78	859	78	78
运维成本/元	3605	3605	3181	3694	3259	3259
折旧成本/元	10299	9088	8780/9950	10090	8903	8903
碳收益/元	165	306	399	306	399	399
深调补偿/元	47600~89250	17850~47600	0	47600~89250	0	0
售电收益/元	26954	40430	118913	26954	121291	118913
售热收益/元	0	0	0	0	0	3393
总收益/元	37571~79221	21460~51210	37467/36297	36643~78293	39644	40659

运行年限	收益单位	机组自身变工况		火-储耦合系统
运行年限	收益单位	20%~100%额定负荷	30%~100%额定负荷	20%~100%额定负荷
1年	万元	2386~3710	1837~2783	释热1：2426~3750 释热2：2458~3783
13.9年	万元	33168~51578	—	—
16.03年	万元	—	29442-44607	释热1：38888~60119 释热2：39405-60636

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