光伏光热互补的全光谱制氢机理研究

Solar hydrogen production is considered to be an important way to solve the energy and environmental crisis. However, the efficient-energy-conversion mechanism of solar hydrogen production process has not been fully revealed, and the matching mechanism between processes is still unclear. Consequently, the development of solar hydrogen production is limited..This study integrates multiple disciplines, such as spectral frequency division, photovoltaic utilization, photothermal utilization, thermochemical utilization and electrochemical utilization. Firstly, based on the idea of "energy matching, waveband matching, and energy-level matching", the energy conversion mechanism of solar energy – electric energy – thermal energy – chemical energy is studied from the perspective of thermodynamics. Occurrence mechanism of irreversible loss during energy conversion process is explored. Maximum efficiencies and influencing factors of each process are clarified, and efficient conversion path of solar energy – chemical energy is proposed. Secondly, for the actual process, based on multiphysics-coupling analysis method, the numerical models of frequency division, photovoltaic conversion, photothermal conversion, hydrogen production processes are established. Influences of key process parameters on energy transfer characteristics and solar-to-hydrogen efficiency are analyzed. Efficient full-spectrum solar hydrogen production method with photovoltaic-photothermal complementation is proposed. The theoretical solar-to-hydrogen efficiency is expected to exceed 45%. Finally, the full-spectrum solar hydrogen production prototype is built to verify the correctness of the energy transfer mechanism and the feasibility of the full-spectrum hydrogen production method. The project results will provide new ideas and methods for the research and development of solar hydrogen production.

太阳能制氢被认为是解决能源环境危机的重要途径。而太阳能制氢过程能量高效转换机理尚未完全揭示，各过程间匹配机制尚不清晰，限制了太阳能制氢的发展。.本研究交叉光谱分频、光伏利用、光热利用、热化学利用与电化学利用等多个学科领域，基于“能量匹配、波段对口、品位耦合”的思路，首先，从热力学角度研究太阳能-电能-热能-化学能转换机理，探索转换过程不可逆损失发生机理，明确各转换过程极限效率与影响因素，指明太阳能-化学能高效转换路径；其次，面向实际过程，结合多物理场耦合分析方法，建立分频-光伏-光热-制氢过程数值模型，分析关键过程参数对能量传递转换特性与太阳能制氢效率的影响规律，提出光伏光热互补的太阳能全光谱高效制氢方法，预计太阳能理论制氢效率达到45%；最后，搭建太阳能全光谱制氢原理样机，验证太阳能全光谱高效制氢机理正确性与方法可行性。项目成果将为太阳能制氢研究与发展提供新的思路与方法。

提高太阳能制氢效率是降低太阳能制氢成本，实现其规模化应用的关键。本项目首先从热力学角度挖掘太阳能至氢能全流程效率提升潜力，进一步提出太阳能全光谱制氢新方法，并通过数值模拟与实验方法验证太阳能全光谱制氢方法的可行性。根据原定研究计划，主要研究内容和结果如下：（1）从热力学角度研究了太阳能-电能-热能-化学能转换机理，明确了各转换过程极限效率与不可逆损失的影响因素，全光谱利用过程的不可逆性是太阳能制氢效率低的重要原因；（2）分析了聚光、分频、光伏、光热与制氢等过程能量转换特性与相互影响关系，提出了光伏光热互补高温电解水制氢、光伏光热与甲烷热化学互补制氢等多种太阳能全光谱高效制氢方法，制氢效率超过45%；（3）研制了太阳能分频光伏光热互补实验台、热电互补制氢反应器以及太阳能全光谱制氢原理样机，实验验证了太阳能全光谱制氢机理正确性与方法可行性。本项目完成了原定研究目标，所得研究成果为开发太阳能全光谱制氢技术提供了理论依据，能有效提高太阳能制氢系统的效率，加速太阳能制氢技术发展。本项目公开发表国际SCI期刊论文6篇、国际/国内会议论文5篇，申请发明专利4项，其中授权1项。