基于太阳能和朗肯循环的热电氢联供系统

A combined heat power and hydrogen production system based on solar energy and Rankine cycle

随着世界各国对太阳能产业发展的日益重视,太阳能高效利用技术已成为新能源研究的热点。然而,由于太阳能具有间歇性、波动性及低能量密度等特点,造成太阳能在存储和利用过程中存在储能成本高、工艺复杂、整体利用率低等问题。太阳能发电与制氢技术的有机结合可将太阳能转化为氢气进行存储,实现能源间的高效转化与利用,可有效解决上述问题。本文提出了一种基于太阳能和朗肯循环的热电氢联供系统,系统主要由碟式太阳能集热器(SDC)、固体氧化物电解槽(SOEC)及朗肯循环(RC)组成,可同时提供热能、电能和氢气。建立了热电氢联供系统热力学模型,对系统及其子系统进行了参数分析,得到工作温度、电流密度、辐射强度等运行参数对于系统能量和㶲效率的影响,并确定了系统各部件㶲损产生的内在原因。结果表明,高辐射强度、较高的运行温度和电流密度可以提升系统热力学性能,系统联供效率和制氢效率分别达49%、25%,最大㶲损发生在碟式太阳能集热器,约占总㶲损的50%。

With the world's increasing attention to the development of the solar energy industry,the efficient use of solar energy technology has become a hot spot of renewable energy research.However,because of the intermittent,fluctuating,and lower energy density characteristics of solar energy,there are some problems in solar energy storage and utilization,such as high cost,complex process,and low overall utilization rate.The organic combination of solar power generation and hydrogen production technology can convert solar energy into hydrogen for storage,which realizes energy-efficient conversion and utilization and effectively solve the above problems.This study presents a combined heat power and hydrogen production system based on solar energy and the Rankine cycle.This system mainly consists of a solar dish collector,solid oxide electrolyzer,and the Rankine cycle,which can simultaneously provide electricity,heat,and hydrogen.The system's mathematical model is established,and the parameters of the system and its subsystems are analyzed.The effects of operating parameters such as operating temperature,current density,and solar radiation on the system energy and exergy efficiency are obtained,and the internal reason for the exergy destruction of each system component is determined.The results show that high radiation,relatively high operating temperature,and current density can improve the system's thermodynamic performance.The total efficiency and hydrogen production efficiency are 49%and 25%,respectively.The maximum exergy destruction occurred at a solar dish collector,taking up 50%of the total exergy destruction.