应用于中高温增强型地热系统的有机朗肯循环经济性分析  

Economic analysis of ORC for middle-high temperature enhanced geothermal system

作　　者：彭瑞冰 廖胜明[1] PENG Ruibing;LIAO Shengming(School of Energy Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]中南大学能源科学与工程学院,湖南长沙410083

出　　处：《应用科技》2019年第1期56-61,75,共7页Applied Science and Technology

基　　金：青年科学基金项目(51606225)

摘　　要：为了更有效利用中高温地热能源,对应用于增强型地热系统的有机朗肯循环进行了热力性与经济性分析。建立有机朗肯循环热力学模型,基于热力学第一与第二定律进行分析,选取适用于中高温地热的最优工质。结果表明Cyclohexane表现出最佳的热力学性能。以Cyclohexane为工质,将静态投资回收期和生命周期内的平准化发电成本作为经济性指标,考虑增强型地热的地下井部分的投资与运营维护,进行经济性分析。结果表明,随着地热井深度的增加,静态投资回收期缩短至一半,但后期下降非常缓慢。平准化发电成本也随着钻井深度的增加而降低,之后达到最小值。敏感性分析表明,增强型地热的地上设备成本和上网电价分别对平准化发电成本和静态投资回收期有较大影响。In order to utilize middle-high temperature geothermal energy more efficiently,this paper analyzes the thermodynamic and economic performance of organic rankine cycle(ORC)for enhanced geothermal systems(EGS).The ORC thermodynamic model was established and a thermodynamics analysis was carried out based on the first law and the second law of thermodynamics.selecting the optimal working fluids suitable for the middle-high temperature geothermal system.It was found that Cyclohexane showed the best thermodynamic performance.Taking Cyclohexane as the working medium,and the levelized cost of energy within the static payback period of investment and life cycle as economic indicators to analyze economic performance.The investment and operating&maintenance of the underground well in the enhanced geothermal system were also taken into account in the analysis.Economic analysis results show that with the increase of geothermal well depth,the static payback period of EGS is half-shortened,however,such decrease is very slow in later period.At the same time,the levelized cost of energy steadily declines and then reaches the minimum value.Sensitive analysis demonstrates that the enhanced geothermal equipment cost on the ground and the feed-in tariff price have greater impact on the levelized cost of energy and static payback period.

关 键 词：ORC 增强型地热 中高温地热 热力学分析 有机工质 地热井深度 井成本 经济性分析 

分 类 号：TK529[动力工程及工程热物理—热能工程]