Cattry Alexandre, Johnson Hannah, Chatzikiriakou Despoina, Haussener Sophia
École Polytechnique Fédérale de Lausanne (EPFL), Institute of Mechanical Engineering, LRESE, 1015 Lausanne, Switzerland.
Materials Engineering, Toyota Motor Europe NV/SA, Hoge Wei 33, 1930 Zaventem, Belgium.
Energy Fuels. 2024 Jun 22;38(13):12058-12077. doi: 10.1021/acs.energyfuels.4c00936. eCollection 2024 Jul 4.
Photoelectrochemical (PEC) systems are promising approaches for sustainable fuel processing. PEC devices, like conventional photovoltaic-electrolyzer (PV-EC) systems, utilize solar energy for splitting water into hydrogen and oxygen. Contrary to PV-EC systems, PEC devices integrate the photoabsorber, the ionic membrane, and the catalysts into a single reactor. This integration of elements potentially makes PEC systems simpler in design, increases efficiency, offers a cost advantage, and allows for implementation with higher flexibility in use. We present a detailed techno-economic evaluation of PEC systems with three different device designs. We combine a system-level techno-economic analysis based on physical performance models (including degradation) with stochastic methods for uncertainty assessments, also considering the use of PV and EC learning curves for future cost scenarios. For hydrogen, we assess different PEC device design options (utilizing liquid or water vapor as reactant) and compare them to conventional PV-EC systems (anion or cation exchange). We show that in the current scenario, PEC systems (with a levelized cost of hydrogen of 6.32 $/kg ) located in southern Spain are not yet competitive, operating at 64% higher costs than the PV-driven anion exchange EC systems. Our analysis indicates that PEC plants' material and size are the most significant factors affecting hydrogen costs. PEC designs operating with water vapor are the most economical designs, with the potential to cost about 10% less than PV-EC systems and to reach a 2 $/kg target by 2040. If a sunlight concentrator is incorporated, the PEC-produced hydrogen cost is significantly lower (3.59 $/kg in the current scenario). Versions of the concentrated PEC system that incorporate reversible operation and CO reduction indicate a levelized cost of storage of 0.2803 $/kWh for the former and a levelized cost of CO of 0.546 $/kg for the latter. These findings demonstrate the competitiveness and viability of (concentrated) PEC systems and their versatile use cases. Our study shows the potential of PEC devices and systems for hydrogen production (current and future potential), storage applications, and CO production, thereby highlighting the importance of sustainable and cost-effective design considerations for future advancements in technology development in this field.
光电化学（PEC）系统是实现可持续燃料加工的有前景的方法。PEC装置与传统的光伏 - 电解槽（PV - EC）系统一样，利用太阳能将水分解为氢气和氧气。与PV - EC系统不同的是，PEC装置将光吸收器、离子膜和催化剂集成到一个单一的反应器中。这种元件的集成可能使PEC系统在设计上更简单，提高效率，具有成本优势，并在使用中具有更高的灵活性。我们对具有三种不同装置设计的PEC系统进行了详细的技术经济评估。我们将基于物理性能模型（包括降解）的系统级技术经济分析与用于不确定性评估的随机方法相结合，同时考虑了PV和EC学习曲线在未来成本情景中的应用。对于氢气，我们评估了不同的PEC装置设计选项（使用液体或水蒸气作为反应物），并将它们与传统的PV - EC系统（阴离子或阳离子交换）进行比较。我们表明，在当前情景下，位于西班牙南部的PEC系统（平准化氢气成本为6.32美元/千克）尚不具有竞争力，其运营成本比光伏驱动的阴离子交换EC系统高64%。我们的分析表明，PEC工厂的材料和规模是影响氢气成本的最重要因素。使用水蒸气运行的PEC设计是最经济的设计，其成本有可能比PV - EC系统低约10%，并有望在2040年达到2美元/千克的目标。如果加入阳光聚光器，PEC生产的氢气成本会显著降低（在当前情景下为3.59美元/千克）。采用可逆运行和CO还原的浓缩PEC系统版本表明，前者的平准化储能成本为0.2803美元/千瓦时，后者的平准化CO成本为0.546美元/千克。这些发现证明了（浓缩）PEC系统的竞争力和可行性及其多种应用案例。我们的研究展示了PEC装置和系统在氢气生产（当前和未来潜力）、存储应用以及CO生产方面的潜力，从而突出了可持续和具有成本效益的设计考虑对于该领域未来技术发展进步的重要性。
