摘要
地热能具有绿色清洁、稳定可靠的优势,具备大比例接替传统化石能源的潜力。我国地热资源储量丰富,分布广泛,但地热发电利用远落后于世界先进水平。热伏发电技术在中低温地热开发与利用方面具有较高的应用潜能和价值,但其规模化应用仍极具挑战。采用模块化设计提升热伏发电机装机容量是切实可行的。本文提出了一种镜像布置的模块化热伏发电机设计方案,可依据不同的热源形式,灵活调整发电单元数量;换热器采用紧凑式设计,有助于提升系统的体积功率密度。团队据此设计研制了热伏发电样机,并在深圳大学中低温地热热伏发电系统测试平台上对其性能进行了综合测试。结果表明,在冷却水流量3.3 m^(3)/h、温度20℃和加热功率9 kW运行条件下,热伏发电机最大输出功率达到了136.5 W,体积功率密度可达26.9 kW/m^(3),系统发电效率能够达到理论最大热电转换效率的82.5%。鉴于目前热电模块的热电优值(ZT)仅约为0.5,若ZT值达到1~2,在同等条件下,热伏发电机最大输出功率可达1.69~2.63 kW,体积功率密度可达338.3~518.8 kW/m^(3),最大热电转换效率为10.5%,可达理论最大转换效率的92.8%。此时,本文提出的热伏发电机模块化设计方案将更具推广应用价值。
Geothermal energy,widely recognized as a green,clean,stable and reliable resource,exhibits significant potential to replace traditional fossil energy.Geothermal resources are abundant and widely distributed in China,but geothermal power generation technology in China remains far behind global advancements.Thermovoltaic power generation technology shows great application potential in the low-and medium-temperature range,however,its large-scale application remains challenging.Modulization is a promising method to scale up the installed capacity of a thermovoltaic generator(TEG).This paper proposes a modular TEG with symmetrical arrangement of the heat sinks,which can be installed with different number of thermoelectric modules depending on the heat source types.The heat sinks employe a compact design to increase the volumetric power density of the system.A modular TEG was developed and tested at Shenzhen University on the test platform for low-and medium-temperature geothermal thermovoltaic power generation system.The TEG yielded a maximum output power of 136.5 W and volumetric power density of 26.9 kW/m^(3),under the conditions of cooling water flow rate of 3.3 m^(3)/h,temperature of 20℃and heat input power of 9 kW.The relative thermoelectric conversion efficiency reached 82.5%of the maximum theoretical value,which was achieved with a figure of merit(ZT)of 0.5 for the current module.If the equivalent ZT value can be improved to 12,under the same operating conditions the maximum output power of the TEG can be as high as 1.692.63 kW,and the volumetric power density can reach 338.3518.8 kW/m^(3).Accordingly,the thermoelectric conversion efficiency would increase to 10.5%,or 92.8%of the theoretical maximum value.Under this scenario,the modular design of the thermovoltaic generator proposed in this paper can achieve higher application value.
作者
龙西亭
李书恒
谢和平
孙立成
皋天一
夏恩通
李彪
王俊
李存宝
莫政宇
杜敏
LONG Xiting;LI Shuheng;XIE Heping;SUN Licheng;GAO Tianyi;XIA Entong;LI Biao;WANG Jun;LI Cunbao;MO Zhengyu;DU Min(State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering,Shenzhen University,Shenzhen 518060,China;College of Civil and Transportation Engineering/Guangdong Provincial Key Laboratory of Deep Earth Science and Geothermal Energy Exploitation and Utilization,Shenzhen University,Shenzhen 518060,China;College of Water Resource&Hydropower/State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu 610065,China)
出处
《地学前缘》
EI
CAS
CSCD
北大核心
2024年第6期215-223,共9页
Earth Science Frontiers
基金
国家重点研发计划项目(2021YFB1507403)
深圳市高等院校稳定支持面上项目(20220810180129001)
国家自然科学基金项目(12075160)
自然资源部科技战略研究项目(2023-ZL-40)项目来源:中华人民共和国自然资源部
四川省自然科学基金项目(2022NSFSC0218)
深圳市基础研究面上项目(JCYJ20220531102012028)。
关键词
热伏发电机
模块化
中低温
地热资源
体积功率密度
thermovoltaic generator
modularization
low-medium temperature
geothermal resource
volumetric power density
